TWiP 200: Parasites without borders

from microbetv this is twip this week in parasitism episode number 200 recorded on november 2nd 2021 [Music] [Music] i'm vincent dracaniello and joining me today at the incubator in new york city dixon de pommier hello there vincent and everybody else i can't tell you what the weather's like because there are no windows at the incubator well there are but they're covered up well i can't really tell but it's a great day out there i can just tell you it's a great day a little bit raw no precipitation but i think the humidity is around 55 to 60 percent it does feel that way and uh it's an appropriate day for 12 200 because it's election day not 12 12 minutes with [Laughter] who's confused it's election day in the united states it is election day also joining us here at the incubator daniel griffin hello everyone and joining us remotely from glasgow scotland christina naula hi hi everybody hello that's good we did invite christina to come but it was just too far for her that's right that's right well i think the travel um ban on uk citizen only finishes next week anyway ah yes oh so you can't leave the uk or you can't go elsewhere no i i think i can't enter the us unless i have family or i am family or i'm a special person but i am in a way you're already involved to us not in the way needed but i think that is i'm gonna finish on the 8th of november i see i also don't have a proper exam a proper vaccine so that would be another hurdle but it's good to be here from glasgow too so indeed anyway special episode 200 we thought we'd gather here we haven't been dixon has not been with us for some time right that's true i've been a remote from fort lee new jersey and i have seen last week daniel that was the first time we uh recorded together right we're seeing a lot of each other yes we are we're almost done with that right for me it's nice it's nice to see everyone again well yeah i think we have no plans but you could always pop in any time daniel i'm here recording most of the time and that was part of the feature of the incubator that we could be here right right and so i in fact got a very long table that we could all sit at yes it worked out perfect and if no one's here i have a nice long table to work at that's right that's right which you guys can see because the this wide shot um is showing that well we were we were reminiscing before dixon and i going through when i joined twip which was episode 80. and here we are at episode 200. so this is a good time to reminisce so dixon and i started twip after twiv it was the second i think and i said look dixon had started twiv with me in 2008 and it had been going for a while and i said you know dixon your thing is parasites why don't we do it this week in paris yeah you remember it's a great idea and so uh we started and for the first 20 some each episode was a different parasite you remember yes i do and then after that we said okay what do we do next we started doing papers right and then at some point daniel was showing up i said clinical cases are missing in our i actually said that and i said i know just the person who would agree to do this and he was just down the hall he didn't he wasn't there from the beginning no no that's right he joined the golf lab and colombia and so forth and you and daniel used to talk all the time he would come in and stop at your desk and chat with you and then one day you said to me i think we should have daniel on twit and i said okay yeah so that that actually happened after daniel and i co-attended the annual meeting for the american society for tropical medicine and hygiene and i drove down and he drove with me and that that's when we really got to know each other because that's a four-hour drive from new jersey to washington it seemed longer it was a that's now he tells me you know i get this data all too late you know i could have dropped you off in baltimore you know that really would have been shorter and so here we are now 200 we have had um daniel and then not so long ago christina joined us uh to give a different perspective from uh across the waters indeed and so uh here we are the twip quad fecta there you go and we'd actually plan to have a little audience but i don't think there's much room in here for an audience so no i don't think that's in the plans unless we knock down this wall one day but the space on the other side's nice right yeah to keep separate so actually um there are several athletic arenas not too far away from here that you could uh avail yourself of if there are no games madison square garden is about two blocks away yeah so you could sell seats yeah you know one night i was walking to the train and above the garden there was a big billboard advertising the next act right right and up there was joe rogan really yes joe rogan and i mean go figure go figure go figure and you know it's funny when i was in austin recording the lex friedman podcast he got a phone call during the podcast he said i have to take this and it was joe rogan right right and he said i want to talk to this guy raci and ello you know him and i heard the voice i never no i don't know who he is okay i'm waiting for the call but he will i don't know maybe he thought that the lex friedman was enough anyway this is twip and so let's do uh our thing here and we have a case from last time daniel what did we have sure let me um let me remind everyone who's tuning back in and uh tell a short story to those who are tuning in for the first time the last uh twit twit 199 we finished off with the mystery case of a gentleman in his 40s who has been having repeated intestinal issues we mentioned he'd been diagnosed with giardia treated he got better got it then again about a year later again not feeling well comes to see me actually referred to me by a gastroenterologist because his stool testing had shown blastocystis hominis and endo limax nana i was asked to weigh in on what might be going on so we got a little bit more background he lives in the new york tri-state area um he is single he's active socially with uh different partners he did not have any medical problems prior to this or other than this i mentioned he was taking prep pre-exposure prophylaxis to protect him against getting hiv he is hiv negative he often goes into the city itself for these social experiences with the different partners his exam and labs were really unremarkable the only remarkable issue were the stools i mentioned last time that we had gone ahead and we had done a therapeutic trial with metronidazole which had no impact on symptoms um all right i think we left it there we did christina can you take that first email yes i can ingrid writes dear tripp team i really appreciated how christina's case study for case 199 had the kind of difficulties of diagnosis red hearings testing problems etc that are probably common in real life clinical practice that was great and have the site benefit that only a modicum of brave soul sent in guesses and they all included interesting thought processes behind their guesses not just part scrapings of a google search i love twit including the writings but sometimes get a teeny bit tired of listening if there are huge numbers of them every time especially if most of them are the same fear guesses left enough time for a paper i had caught the news earlier about this first ever successful malaria vaccine and was hoping to hear the twit team's reaction thanks for covering it thanks for all the fun cases information and friendly discussions on twitter and twivo ital ingrid from berkeley and she carries on to say big rain all day today first big rain that i can remember in two years like the old days standard and frequent fall winter rain that i remember from the 60s into the 80s i'm guessing this is the official end of this year's fire season and crossing fingers for enough more rain this winter spring to ease our drought drought p.s vincent i really like the new two color background on the wall behind you in the incubator and i'm just looking at it [Laughter] big improvement on the plane wide and the colors are subtle not overpowering just right i actually can only see one color i'm sorry i've moved since the last time we recorded it was recording over there and now there's just a chip so christina there's a behind this picture there's a chip on the wall and everybody kept noticing it and saying they thought it was a blemish on their screen so i had to put up a picture to cover it was that crazy that's funny well this background will change uh we're working on it but we're not there yet right uh dixon can you take the next one they certainly can andrew writes keora from pangarora book one yay but i'm but i am still case guessing i am addicted now and looking forward to seeing who wins a book on twit 200. i have an idea for the book signing event make a film and call it the signing you can work out among yourselves who plays the jack nicholson part and who has to explain to amy why there is an axe damage to the door incubator or to the incubator door on with the case from the gentleman who gets repeated cases of intestinal issues my thinking is that he has what was erroneously called gay bowel syndrome that's in quotes it is basically caused by a larger than normal dose of infectious matter that is passed during sexual activity the dose is large enough to overrun the immune defenses so that an acute infection that normally would be quickly dealt with becomes symptomatic until the body has a chance to ramp up and clear out the pathogen the sort of activity required is not restricted to gay sex i imagine that practicing safe sex would prevent future problems nah andrew well just to let everyone know since we are gathered here today [Music] daniel and dixon autographed the 100 copies of parasitic diseases seven and so there now it will be shipped out i had no longer have an excuse gentlemen not to ship them out not only that you're not very far away from the one of the largest post offices in the united states no that's no longer there that's a train station oh that's in fact a very nice one have you visited take it all back daniel moynihan station i i know are very beautiful that's so silly it is really nice yeah no more post-it upgrade no it's great you know i take it back anyway so you will be getting your books perhaps by the end of the year in due time this is like the novavax vaccine there's a very wide confidence interval here on the delivery by the end of the year right that's right all right but they filed for approval in the uk that's great it's not trip they got approval in india yesterday i believe so we're perfect so the bookings maybe those books will be coming out you know you never know you never know so christina in a recent twit we discussed the the novavax results were submitted as a preprint and i mentioned that you had been part of the uh the trial yeah i heard that then after i said maybe that's that's uh what do they call a confidential medical information person i think you sh i think you shared it actually on twitter so that makes it okay yeah you're not violating hipaa do you have hipaa rights in scotland do we have to grant you hipaa rights i'm not actually sure what they are so maybe we do maybe we don't know nobody is nobody has christina all right daniel why don't you take that third and last one certainly martha writes dear twip i will be brief i just got the heads up at the online virology course that a new twit was coming up of course i am still sending guesses although i want a book a few episodes back the case of the man with the complaint of recurrent abdominal discomfort no other complaints treated for giardia in the past treated now with metronidazole with no resolution his exam was otherwise normal labs only significant for blastocystis and endolymex nana at some point it was held to be true that blastocystis was not a pathogen and did not cause symptoms in immunocompetent persons but it seems some immunocompetent persons do have symptoms it also appears that there are some blastocystis that are resistant to metronidazole so perhaps of course of the alternative treatment paroma myosin wishing you all the best martha and that listeners is it for our guesses three three and one has already won a book so there's actually just two wow well i know we had someone saying there were often too many guesses and we weren't able to you know this is a bit of a stumper actually say dixon two but two of these three people have one books two out of three oh my gosh there's even even a number generator you just win ingrid wins by default there you go that's right ingrid send me your address twip at microwave.tv and you're in california that's all i need and perhaps by the end of the year you'll get one of these freshly signed that's right volumes that's right so now i guess it's up to us to add our little two cents worth well i mean i was uh obviously i'm old enough to be part of the uh scene when um the aids epidemic began and i was smack dab in the middle of the infectious disease units because obviously my subject is parasites so being the only person at columbia's medical center that knew anything about parasites other than clinicians who had treated them um i was always included into these grand rounds and i learned about the development of gay bowel syndrome and how prejudicial that term is and then how uh energy we were to exploring further what the causes for these people's demise was and uh you know you know about these public displays of dismay the band played on etc to let everybody know that uh if you're of a certain social group you are basically excluded from basic medical care and that that all has changed now but they took an epidemic to cause that to happen so thinking back along those lines i think one of the guesses was spot on and that was the one i read because indeed gay down syndrome was later unchanged to a condition which means that your body just becomes overwhelmed with all kinds of non-infectious and infectious agents they don't have to be infectious they just be microbial part of the microbiome of another person and as a result of that there is these transient syndromes which don't add up when you look at what they mean did you have fever did you have diarrhea did you have discomfort did you did you sleep did you not sleep all these and everybody had a different story with regards to that and so it became very confusing as to what was going on until they finally figured it out so i think what you're really looking at is an overwhelming load of microbial life through the oral route that induces uh temporary changes in a person's basic um symbiosis with their own microbiome and it causes disruptions which results in these constellations of signs and symptoms undefined untreatable and uh just stop doing that and and practice safe sex and all goes away so dixon you don't think blastocystis and endolymex necessarily have anything to do with this well with repeated uh negative results from metronidazole it's unlikely that both of them are resistant to metronos he's just reacquiring them yes he develops his partnerships uh throughout the year so because those are two common para nun parasites that inhabit the human gut tract so it's likely that he was visiting some of the original people that he might have acquired those microbes from to begin with that's my view okay she really christina jump in christine do you want to jump in from glasgow i denies with that one to be honest i don't really know much about either blastocystis or endo limax but looking at the life cycle of plasticities i thought it was hugely interesting and i think yeah maybe a parasite that we could cover yeah should we spend a moment just talking about what is the story of blastocystis remember we used to do a good job saying all right we've mentioned it let's go through the life cycle so christina shall we let you yeah i'm just trying to actually make it a bit smaller on my screen so i can see it as a whole so well i'm read so i'm looking at the life cycle actually on the cdc um because i don't think you have actually you're showing a life cycle in no you don't show a life cycle and parasitic disease is seven so um it's okay to have a look at the cdc ones i think i think we don't show it but we don't show it because we don't think it's a parasite that's that's basically why we don't show it you didn't show underlying either right uh yeah i can bring that up as well but actually the first sentence that it says here in the blastocystis life cycle is that the life cycle of blastocystis is not yet understood including the infectious stage and whether and which of the various morphologic forms of this polymorphic organism that have been identified in stool or culture um constitute distinct biological stages um in the intestinal tract of the host it's actually not not very much is known about it and if you have a chance to look at the life cycle on the cdc website i think all you need to do is put in your google search cdc um parasites a to z and then you can follow the b and find it here actually it's got lots of really interesting life cycle firms so it's got in in the intestine we have an amiboid form and then a form that is called granular another form that is a mitotic form which um presumably divides by binary fission and a vacuolar and assessed form and these latter two forms are the ones that um one could possibly find in feces and that are thought to be potentially infectious so um [Music] but that is really really not much knowing about it at all and i don't know if dixon with your many years of experience maybe um maybe you can add a bit to that sketchy life cycle yeah the best way to put it yes christina best way to put that is many years of inexperience because it's it's it's been a confounding organism for many many years and and you've got multiple vacillating opinions about it in the literature there's some say oh yeah it's a pathogen because i have a patient that had this and they got very sick and then i treated them and they got better and then the other people say it might be a pathogen but i haven't been able to treat it because it didn't respond to anything i gave them it's been cultured and it's an anaerobe that's why they used metronidazole but that did not this is probably one of the most resistant anaerobic infections to that drug because bacteria even respond to metronidazole that it's used for uh treating amy biases and virtually other anaerobes like giardia as well so um it's an it's a conundrum basically that's what it basically boils down to and i think there will never be any definitive uh results from this because it's all of it's very very difficult to find only blastocystis in a patient and you can see right now that uh endolymic sana accompanied that protozoan and uh and so you know you're stuck with trying to choose between which one was causing all those symptoms and the answer was neither one so that's why we didn't really think of including a life cycle a b we didn't know what the life cycle was so how could we include it what about vincent do you have any comments did you want to jump in daniel do you remember twip 99 uh-oh you know i that's what i was probably going to bring up because we we talked about an interesting paper and we talked about the fact that the genetic diversity of blastocystis is about as broad as the genetic diversity of gram-negative rots i mean it is an incredibly diverse group of organisms that we're calling blastocystis so you know and and in that paper i think i think this was the episode where we discussed the paper it looks like there is a certain subset of blastocystis organisms that might be the ones that might be you know keep qualifying here might be pathogenic and um so they did studies where they looked at you know this is often the case you give people therapy doesn't do anything but other people you give them therapy and coincident with therapy they get better and so they were looking at the the genetics of blastocystis suggesting that you know in this huge group there might be a subset of blastocystis organisms that do cause symptoms where treatment can make them better but the vast majority of time it's a commensal it's not causing any issues and uh that that's actually sort of what my thought was after this treatment we see endolymex nana which really does not cause symptoms there's that very interesting case of the gentleman with advanced immuno suppression who ended up with an invasive endolymex nano tumor right yes um and that that's it was very exciting i think i think i was in um in southern india like right as that paper came out and that was like what we were all talking about i was hanging out with like-minded people who want to talk about such things and then we have that blastocystis so so my my take on this was that this was a dysbiosis being triggered by fecal exposures and and when i got into the details of these social interactions they they involved um sexual practices that that had a fecal exposure and that's really seemed to be the timing when he would have a successful encounter engage in one of these particular sexual practices that would put him at um exposure for fecal material then he would have this dysbiosis you know sometimes he would end up with a pathogen right a couple of times he got giardia which i think were true pathogens treated got better giardia treated got better but then he developed this treated no impact on treatment and that's what i think it is that was my clinical impression in this case um he's actually someone i continue to work with with a gastroenterologist um trying to restore a proper microbial gut balance so the title of that trip 99 you get your polar bear from your nana what was the basis for that so when you know one of the things that we have to do in our training in dixon probably is that you have to look at under the microscope and identify the the different organisms and so there's a polar body yeah and so that's one of my one of my mnemonics it's great that's great yeah well so if you're interested in what i think i remember we're very interested in what you do no it's okay you're going to hear it anyway you um have talked about it before that was one episode and in the parasitic diseases lecture series there's a lecture just to cases where it's tough to figure out what's going on and this was that's two of them that's right the hosts uh the the microbes involved so uh then looking at other cases it often this is often seen right gastrointestinal problems you get both of these isolated there's nothing else unusual right and you know there's the whole flora which it's there so people don't make any note of it and it often happens after sexual encounters so i would say yeah these two somehow together are causing uh this um imbalance but uh maybe you know many people have nana right many many many people so maybe together with blastocystis that causes it so i thought these two organisms were the diagnosis but it seems to me that it's not it's more like a dysbiosis and i think that we don't really know in the end right yeah yeah i mean that that's that's true i mean now that we've gone ahead and we've got them to start using um you know kefir and yogurt and you know different things pro a probiotic approach um we're seeing some improvement um so it's sort of but but i will say this is interesting um i don't know if this is a case we ever presented but we had a gentleman who went to south africa with his wife and there was a water shortage which you know happens a lot in south africa and so there were issues with hygiene and he came back with blastocystis having you know horrible diarrhea he was treated and coincident with treatment got quite better so i do think there are certain subsets of blastocystis i think you know the sort of genetic studies suggest that but a lot of times um you know this is something clinicians have not seen before the tendency is to to treat it you don't always necessarily need to and like in this case um the treatment didn't seem to make a difference right so you just told him to have kefirs and yeah we talked about how to restore his proper gut microbiome we also talked a little bit about like you know if he enjoys this particular um sexual activity and you know as we established a pattern it really seemed coinciding he'd get better he'd be feeling great then he would go ahead and get the same exposure and there wasn't always anything exciting in the stool except for he would have symptoms and they would last for a three-month period of time and so can i ask is um when you see symptoms so you know in men who have sex with men there are the insert the insertive and the insertion right are those the right words yeah so does it correspond with either one it really was sort of an oral anal um stuff all right okay yeah that makes more sense that makes more sense there's not much you can do about that dixon nothing except uh caution them and you're doing your job and if they don't want to listen that's their fault sure the other uh caveat on this one is that if this person was not um gay and did not acquire this through his sexual activities these commensal organisms that are acquired through fecal contamination could be indicators of microbial life that is not parasitic that is not you know might they'll be bacterial rather than protozoa so you'll you'll do stool cultures as well to look for things like shigella salmonella that sort of thing so it's it's good to follow up on them and a lot of times they did turn out to be the cause of their illness one last question so you should see this in women then it shouldn't be restricted to men right that is true that is true do you yeah oh okay makes sense all right i've got one question as well daniel um i did read that you could use alternative drugs as well to treat this did you yeah you didn't do that at all yeah you know that's interesting and i think one of well the one emailer brought that up is because what you know us uh alternative alternative suggestion would be that we just have a blastocystis that is resistant to the metronidazole so blastocystis maybe we have and i would love right if we could genetically type this determine if it's one of the ones associated with pathogenicity um but the other is do you go ahead and use an alternative treatment um such as problems i guess then i wouldn't really kind of tally up with with the coincidental um appearance of the symptoms after a successful encounter yeah and the fact that they tend to have this cyclic they would resolve over time and yeah and we are we're trying the probiotic approach working with the gastrointestinal if he doesn't get better and maybe symptoms get worse that would be reasonable to consider but boy it's been a while since we were all in the same room we used to be in the same room christina when we recorded twip we sat around a a table a round table and i missed that it's fun because you can see people's expressions so much better than on zoom for some reason you know yeah you've actually got a really nice photograph of the three of you sitting at the table and on the parasites without borders webpage yeah yeah yeah yeah that's nice sadly it uh yeah not gonna happen yeah i kind of find you can't really see so much when someone wants to speak so easily or because you can't hear their intake of breath maybe and it's a bit more difficult so but you know christina for years we did audio only right that's true yes of course and very hard to hear when someone wants to talk so often you step on each other all the time right we'd interrupt each other i feel like we did it backwards like now that we're doing the audio i'm sleep deprived i have permanent bags under my eyes i was a better looking man back in the audio days to get older we're all getting older daniel what are you gonna do all right we have a paper for you this should be fun this is dixon's choice actually i will i will modify that my my wife marlene bloom whom i share my life with was sitting at the dinner table and reading um something from the new yorker magazine i believe and it mentioned this paper as a confounding principle of life's continuous exploiting of the possibilities of interactions that's as vegas i can be and then she read me the uh the sort of the abstract to this and it sounded uh perfectly reasonable to uh look into it further and i did and when i did i discovered that it was much more complex than the little blurb that she read to me but nonetheless uh we're up to this so i said why don't we just review this paper and see where it takes us because you will see from our discussion that it doesn't exactly stick with the text of the paper itself and that is the whole point of this is to show you in some ways the difficulties of carrying out experiments when you take them from the laboratory and move them into the field so this is a paper in molecular ecology it's called long-term spatio-temp genetic structure of an accidental parasitoid introduction and local changes in prevalence of its associated wolbachia symbiont i'm sorry would you please repeat that yes indeed van nuys from lund university that's in london sweden university of helsinki and your old alma mater well the department of ecology and evolutionary biology they left out the the university cornell university ithaca new york right oh that's so funny there's no there's no they left it out not only that is this that was the birthplace of modern entomology what's his name no that was the birds that was the original the the the the ant guy who was up there well that's io wilson but eel wilson is at harvard this this that department in cornell became famous there was an insect guy at cornell who you always talked about oh yes he was a chemical and uh ecologist and i will i that's okay my rolodex is turning slower nowadays i'll come up with this name don't worry anyway the the the the participants in this paper uh two out of the three we've actually talked about on twitter we've talked about parasitoid wasps right mm-hmm and wolbachia but we haven't talked about this butterfly which is part of the we have not so uh dixon do you want to start us off here well the the the premise of this research venture is to try to establish a population of butterflies on an archipelago of the uh country of finland that doesn't have this butterfly to begin with they want to introduce a species and see what happens to it so it's a little adventure in ecological invasion basically but in order to do that they have to collect these butterflies from some place and so they go to other islands that have this butterfly and how do they introduce it and that's the problem number one problem number one is that how would you introduce a butterfly into an area that doesn't have them and so you have choices uh you can start with the eggs you can take them off leaves that they deposit them on and you can take the leaves over to the island and you can allow them to hatch and then you can allow the caterpillars to grow up and then they will produce adults and the adults will mate and then you've got a population to study that's one way they didn't do that another way is to collect caterpillars from the environment and just take them because they're easy to see and put them in a little jar or a little cage whatever you choose with lots of leaves to keep them happy until you get them to this island and then open the cage and allow them to escape and hopefully they will choose a similar plant or maybe that same species of plant that's on that island as well maybe they've looked into that part and you've introduced the species this way and the third way of doing this is to take adult butterflies males and females before the mating season just newly hatched and take those to the island and release them and start your populations that way so i was going to ask couldn't you do the chrysalises apparently i get oh i'm sorry that's right yeah because i get criticized like i'm explaining to people like how to go in and out of the airborne isolation rooms with kovid and and i would say just think about like when you're going in and out of a butterfly pavilion people always look at me uh see adam moran when i asked you doctors like yeah that that's not a good analogy most people are not going in and out of butterfly pavilions that's right but i think they do but i think they do they use the cr they transport the chrysalises and that's how you establish them in a different butterfly that's right that's right so you could do that you could collect the chrysalises and then take them or crystallize depending on who you want to pronounce that and let them hatch that's a little risky though because they all might not hatch and they may have predators that would eat the chrysalises that would recognize like birds and things like this so so or you can begin with a laboratory colony you could have a butterfly room just like daniel said and you can allow them to reproduce and produce all their stages and then you can start with the simplest stage which is the egg i would have picked the egg i think and take leaves worth of eggs that they lay on the bottoms where they ate and then let them go into the environment and start from scratch or a laboratory colony start with that to make sure uh that you're gonna avoid something like what happened in this paper so what happened was that they took wild caterpillars from one place and they introduced them to the island and in it inadvertently they also introduced some of the parasites that infect this butterfly species and may be responsible for why it's not found on that island to begin with these are called parasitic wasps parasite it's important right okay well they're they're also called ignomid wasps they're new yeah they're all um the predatory parasite oriented what they do is they catch a victim and then they insert their ovipositor inside the victim and then they lay eggs inside the victim right so how did how did the wasps get there too like you think you would no right you got the eggs but where are these wasps the wasps eggs were inside the caterpillars they were like the trojan horse type of thing so the caterpillars unbeknownst to the investigators carried with them their parasitoid wasps and not only that there isn't just one parasitoid wasp to deal with here there are parasite wasps that parasitize other parasitized wasps so you've got like they liken this thing to a nested set of russian dolls you know what those are called the second wasp that's right now what if that also had a parasite oh it goes on and on it's turtles all the way down that's right that's right dr seuss was right dixon the butterfly is the glanville fritillary butterfly i love the name i love that name this is so in retrospect they should have checked the caterpillars for the parasitoid wasp eggs right i think well i'm not sure because if you look at the maps actually these parasitoid wasps and the hyper parasitoids parasito it was they were already very common and you know very um okay i think that they were essentially everywhere on that archipelago already if you have a we look at that map yes um maybe and i think it was before 1991 so that was actually a long long time ago that they introduced those um butterflies together with all their parasites yeah well would you also consider then this as a flawed site just to select because if you want these to to actually successfully reproduce and maintain a population then you should pick a place that's so remote that only it can survive apart from its parasitoid well it did survive so no of course it did because a balance between yeah the infected and unaffected ones because and i think the parasitoid infects about 30 of the butterflies only so there's only ever it's it's not like in the name of no no sorry i'm i'm jumping ahead there no i took my volvakia mixed up with the wasps uh but i think it's about thirty percent of the um um what are the things called butterflies yes so but i just wanted to take a diversion into this paris story because we have talked about them on twiv because when the wasp injects the eggs into the caterpillar the eggs produce viruses that immunosuppress the caterpillar and those viruses they're not they're encoded in the wasp genome which is amazing right the the and the the wasp delivers them along with the eggs so the genes are encode are integrated into the wasp genome in the ova the virus particles are made they go in with the egg and they immunosuppress they produce proteins that immunosuppress the caterpillar so they don't reject the larva otherwise they would reject them isn't that insidious it's amazing so what's in it for the virus it gets a new host i guess and you may say when did this virus pop onto the scene right because what were wasps doing before that it's really interesting fascinating situation it's amazing that you know with science how everything is connected because we sort of silo sometimes right like i'm a virologist i'm an immunologist i'm a parasite but to understand a lot of these you you need a team right you need people with all the specialties communicating and talking sure that's right so dickson what did they they find this is a 20 year old study right it's an ongoing 20 year old introduction and their results were unexpected and uh they they explained them in ways that made it very difficult for an uninitiated molecular ecologist to actually follow closely because they did a lot of genetic analysis and what they were looking for was expansions and collapses of populations and they were trying to come up with genetic explanations and they did fabulous genetic analysis of not only the uh the butterfly uh but also its parasitoid wasp and then the hyperparasitoid and the wallback you know they looked at the genetics of all four players that regulate populations all right so you just mentioned wolbachia so where did that come in where does that come into this well i believe the wallabachia is injected into the parasitoid wasp by the hyperparasitoid wasp and that kills off the the parasitoid wasp and limits the populations of that parasite of the caterpillar so that the hyper parasitoid wasp is actually helping the butterfly expand their populations and all that was my understanding all of these came in together the hybrid and the parasitoid the butterfly the entire entourage of uh networks of life for these four forms of course were introduced and inadvertently that was the other point this is i think that sorry go ahead go ahead go i just i just wanted i think of all the volback here they actually um kind of make the paracetatoid was more suspect susceptible to infection with the hyper or parasitizing with the hyper parasitoid was that's correct i thought that was quite interesting so i actually came you know that came out of all back yeah in the parasitoid has quite a high cost really for those very much little wasps so it means that the rate of infection in the parasitoid wasp is not 100 from the hyperparasitoid wasp because if it were then obviously they would all be dead and then they would have no more hosts to infect and therefore they would become extinct and they would leave just the butterfly alone but that didn't happen so there's balance between all of these uh pushes and pulls evolutionary pushes and pulls which have in the full explanation of this paper which is very complicated a genetic explanation and it's all to do with bottlenecks of population explosions and collapses due to the acquisition or the uh immunity that's conferred by let's say um no i'm just rejecting that please correct this is definitely a very complicated paper and and we've talked a little about it very challenging to look at these issues so they really sort of took an opportunity to observe and what you see and you know i don't know if this is open access is open access but there's there's a figure two where they're actually following um the the butterfly populations in the different regions and they have them color coded so you've got your orange your green your yellow your blue your red and they they have a table below it because they're they're making the argument that you see an increase a drop at increase a drop and each one is sort of a selection point when you can ask the question is is there a fitness cost to wolbachia that is correlating here and they're going to claim that there's a fitness cost to having wool baking so you could sort of look at your table sure ask a question of how much you know what percent of the population is do we call infected with wool bucket i almost feel like we need a yeah it has a has a wolbaki a symbiote it has symbiont yeah symbionts a symbiote um you know because it is interesting because we you know we use these terms sort of almost excluded but symbiote there might be a certain advantage to the symbiote but there's also a fitness cost to this scenario sure and and i think that's sort of what they're trying to suggest i think suggests this is the strongest term you'd use in this kind of a study so dixon they were originally interested in this idea that when you when a population is introduced in a new area usually you don't have a lot of them that's true and that's where the bottleneck comes from right that's the one that's the first bottleneck and so it's an interesting study to do to see how the population changes sure when you introduce it that's right and i think what they were surprised that it's there was not a lot of change which is what they looked at with their markers and so forth and i think the wasp and the wobakia kind of explain that it does it does and i mean let's do you mind if i drop back a little bit in history of the idea about reintroducing or introducing species into a sterile area and then following what happens sometimes in nature luck favors the prepared mind as louis pasteur used to say and there was an incident where a bunch of wolves were chasing a herd of moose this was um northern uh minnesota uh near duluth and uh there's an aisle off the coast of that uh state called isle grant uh let's say isle royale isle royale and the ice was obviously formed across the great lake lake superior and the moose ran across to the isle royal to escape from the wolves which they did not and then the wolves caught up to the herd and started to cull moose and to obviously do what they do in nature and that is to regulate populations then the following spring when the ice melted there was no way for the moose or the wolves to go back they were stuck on ireland which had no moose or wolves to begin with and that study is ongoing now i mean that that's uh that might be 50 or 60 years old for that study and they've been watching populations of moose and wolves go up and down and they call it the moose spruce wolf triangle of when there's a lot of moose there's they eat spruce then they deplete the spruce then there's a lot of crashing in moose populations then the wolf population crashes because there's no more moose then all of a sudden the moose come back and the you know it's crazy stuff this is a study that everybody gets interested in in ecology for some reason because it's like an invasion of species into new areas and there are books written about invasion of species and so this is a follow up on that with a much more sophisticated way of analyzing the data because in this case they've got genetics to back them up genetics is complicated they're looking at mitochondrial dependency satellite uh dna dependency there's a lot of stuff in here that i um glossed over unfortunately i must say that i didn't dig deep enough to try to derive more meaning from it but the the main thing i got from this in in the end was that if i'm part of this group and we're sitting around a table and we're discussing the results we could be there for a year the results are open to interpretation you cannot control what nature does after you've started the experiment you're watching to see what happens after you've set the clock in motion and you're an observer at that point you're not manipulating the populations you're simply beginning the experiment and then let the games begin and it's a remarkable study from that point because it's very difficult to do these studies imagine going out into the field and collecting all these life forms and then bringing them back to the lab and then grinding them up and getting their dna and then you know and then trying to make meaning from this that has something to do with the crashes and expansions of populations and it's the way life behaves so i admire their courage for just trying this i mean it's not a and it's how long has this study been going on for 20 years notice a lead scientist as a entomologist i think the original experiment was was kind of abandoned and this study just kind of took advantage of of that experiment of re-wilding the this small island with butterfly and has actually then taken the opportunity to look what happened to the various populations on this island and other islands and actually there's so much detail in that paper i spent an entire day just kind of looking at it it was just it was just so amazing for example if you look at that little map you can see three islands that are close together so the one in the middle so tunguy is where they release the butterflies originally and then you've got these other two and a kind of quite genetic analysis they could explain you know in which directions they migrate it just by looking at the genetic you know that's right the genomes of these creatures exactly and um you know for example they could explain that um there was there was not really any migration from sotunga to the lower island which is called fogler although i'm not sure if my finish is up to scratch here um but there was migration to the upper island and you know one explanation they have for that i thought was interesting it's because of the prevailing winds because obviously those those um and and the butterflies they can't really cover that much distance over all open waters i thought that was really interesting and they also looked at the kind of the volbachia infection rate on the different islands and if you kind of look at the top island where you don't have the hyperparacetoid wasp actually on this island that the parasitoids were almost 100 infected or parasitized or symbol symbiosed i'm not sure what the right word is with with wolverine here so nine ninety percent of all the parasitoid was contained bobaccia but on the other islands it was more like 30 and 25 so huge differences and i actually tried to explain it all um it's all hidden in my notes somewhere so i can't easily find the explanation i but you thought there's so much richness of data in there yeah i think it would take a year to discuss even in a group meeting or in a lab meeting so dixon what where's the parasitology here well i mean the parasitology i mean if you're looking at a um an ignorant wasp egg as the parasitic stage of that life form and it gets inside of another animal and it starts to eat and grow and essentially consumes a living organism in the process it reminds me a lot of other relationships like that for instance there are lots of examples of wasps that take spiders for instance the mud dauber wasp and it captures a spider it doesn't kill the spider it paralyzes the spider and then it puts it inside of a mud encased nest and then lays an egg of course the egg hatches and finds the spider and crawls into the spider and eats the spider and that's its meal so that when it hatches it's going to look for spiders right but i wanted to say something more general about studying life forms on isolated islands think back who was the first person to establish this as a methodology for looking at evolution is that chuck it could have been there is a strong resemblance to the very original experiments of a naturalist whose father was a pastor back in england and wanted his son to experience the world so he could explain it better to his parish when he took over the practice and the galapagos islands jump out at you and then you're the man with the proper shaped head it's the one and he doesn't have much hair on the top he's got a lot at the bottom yeah now that's that's why he was selected by the captain because his cat the captain checked his head was that what it was yeah and he had the right shaped head the original naturalist his head did not pass i see i see i see so master and commander is a film with uh a wonderful actor whose name i'm blocking one right now but you will recall his name vincent no yeah i know who you mean i'll look it up go ahead um he's an australian actor and he was a master full captain of the ship and on it was a naturalist and they stopped at the galapagos crow russell crowe right and i i was in love with that movie from start to finish and to watch this naturalist stumble over these islands with his cages of animals and his deadness and he's live that his plants these and bringing them all back to the ship he almost missed one of the ship's exit points and they had to come back to get him and it was a wonderful portrayal of what it was like to be a naturalist on some of these adventurous ships that shipped out like the beagle um this is a modern um homage to the very beginnings of these studies to see how life behaves both in isolation and then put into a different situation because let's face it in the world we live in there's a lot of encroachment and there's a lot of introduction of species into places where they never were before like us for instance when we get involved in the tropics for instance and you build a road from let's say uh belem to the interior to establish a new city like uh the capital of brazil which i'm blocking on right now brasilia of course foreign so building that road exposed all of the workers to organisms from wildlife that could now take advantage of a new host as they progressed towards the center where they were going to build this so these encroachments and invasions and of creating ecotones those are called differences between one ecosystem and another the border between the two that's when that's where the conflict comes in so establishing populations on islands that don't have them creates a situation where they can duke it out with who's ever there already and if the nobody is there they own the island they are kings and then that's the way that comes out but but but but their populations are regulated by other life forms which oh you think this is your island well you i own you because you know that sort of thing and it's it's it's so much fun to look at the depth at which nature has evolved in order to regulate itself from running away with the whole planet and just filling it up with e coli or filling it up with a fish species or it doesn't work that way yeah it doesn't work that way i like the connection with the darwin because you know we maybe we've become like sort of snobs of randomized control experiments where like we we only have one variable you know and here it's just the fact that you can actually learn a lot generate a lot of hypotheses as darwin did just by looking by observing by trying to come up with ideas why why would this be this way why would this happen why do certain you know um organisms have more wolvakia some have less you know anything about wolbach is going to help us understanding parasites because it's such an important organism and here they're just they're observing they're not they're not messing someone messed at some point someone introduced and then they're looking at and saying what can we learn over the 30 years right 1991 it gets introduced so um i think that this is you know and you see the challenges this is not easy but this is very difficult yeah and and not only that there are no controls in this experiment because it's not an experiment yes it's an adventure and uh i i wanted to come back to something daniel just alluded to it too because he said and wolbach is such an important organism remember that with a parasite that people used to catch a lot in west africa called uncle circo vulvulus it's a black fly transmitted worm infection that results in a nodule in your neck or your arm or your leg the adult worms live in the nodule but they produce larvae that migrate under the subcutaneous tissues until they finally find their way into your eyes when that happens you start to go blind they infect all the parts of the eye and eventually the eye coats over with these uh cataract like opacities and the the person goes blind and it's called river blindness what is the cause of river blindness it's the worm of course it's the larvae of course and it turned out none of that was true what was the cause of their blindness and the cause of the blindness was the walbuckia in the larvae if you knock out the welbachia with a drug that detects bacteria only and you infect an animal with an equivalent infection no blindness the worm doesn't cause the blindness the wolbachia causes the worm to cause the blindness and the mechanism for that we don't understand because maybe welbach it triggers a toxin that the worm can produce only with welbachio there and not without and i had the privilege of meeting the person uh who actually discovered the wallback in the larvae of hunger circumvolvulus and he didn't know anything he didn't know what it meant he didn't anything he was an electron microscopist he was not a uh a worm biologist he uh but he discovered it and um he's actually eventually given credit for that so that's a great example of this is a totally unexpected role for this bacteria to be playing in a worm and then there's all these other things that where they sterilize adult female mosquitoes and that sort of thing so well bake has wallpak is probably the ruler of the world as far as we know i mean it's the underlying reason that everything behaves the way it does and how does one organism good it's really really fascinating actually there's actually kind of that the relationship with wolveria with arthropods is slightly different than the relationship with vulva with nematodes so i i think in the nematodes it's always a symbiosis so you know the nematodes need them for survival for example the onco circa i think they get um what do they get i'm just trying to remember some essential amino acids they derive from the volbachia metabolism okay and and actually the bulb that onco cerca cannot reproduce without the volbachia so they are really dependent on each other but in arthropods i think the relationship is more parasitic um you know it's not probably you know how they can feminize the mosquitoes yes or how they can um kind of kill off their male offspring and that that that's not very symbiotic really that's kind of like deleterious that's true that's true by the way so actually you know that even though it's one than the same bacteria and there's lots of different lineages but the roles in these different other phyla is really quite interestingly different so more symbiotic in one area and more parasitic in another in another world like bucheria bencrofty the females you destroy the wolvakia the females lose the ability to reproduce right the guy who discovered that is bill kozak by the way i remember his name yeah okay william kozak and did you probably have on your test right like what is the one west african nematode that doesn't have a wolbachia symbiote i was just going that was just going to be my next question i've always wondered why lower lower doesn't contain well yeah it is interesting though why does it not contain any ball back yeah well maybe because it's transmitted by a different kind of vector it's transmitted by a banded fly right not a not a black fly it's a banned fly yeah so yeah but then you know maybe the deer fly doesn't have maybe the flight doesn't maybe the deer fly doesn't have it but i think the transmission is mostly vertical rather and only very rarely horizontal so maybe it's just maybe it's just not happened maybe once it's established it will kick off and and that hasn't happened in lower law but really interesting actually it's interesting also that you can introduce wall back into a population of insects that don't have it and they will now have it and then you can use that as a control measure for yeah i think that's what they're doing with dengue isn't it absolutely releasing the infection that's right yeah that's right so daniel you can treat some of these uh parasitic infections with the antibiotics to get rid of the wobachia right yes so doxycycline interesting enough yeah so you can actually just go after the wolbachia and i had a case of mancinolosis right not very common right and uh we had some challenges treating it and we ended up using doxycycline so going after interesting yeah going after the wall back dixon why is it a parasitoid not a parasitic would well do you know uh christina why the name no i noted exactly that very same question why is it called a parasitoid and not a parasite yeah well i think actually don't know i don't know well the the it's the alarm it kills the kills the the caterpillar but it's more of a predator than it is a parasite yeah right so they usually classify predators as animals that are larger than their prey right like a lion that goes after uh let's say a gazelle or something uh but in this case it's a tiny little larva that will eat and you've got the ants i got the answer so paratoidism yeah they feed on a living host which they kill yes typically before it can produce offstring whereas conventional parasites usually do not kill their hosts oh that's a bad difference and predators kill their prey immediately so that's the three you don't agree with that no well can't you name some parasites that kill their prey let's kill their hosts yeah yeah lots of them yeah we've talked about them all the time lots of them so that you know that's probably not a good way to differentiate but i was also thinking the predators like i'm thinking the wolves going after the you know the larger animals right they come right away so they're parasites but maybe maybe a conventional parasite is transmitted before it is killed maybe interesting so some predators can't kill by themselves they need to hunt in packs and the lions are definitely like that and so are the wolves yeah and coyotes uh the coyotes don't hunt in packs coyotes eat rodents so they're they're kind of along the side over here uh it's it's it's a it's a false definition basically i think it should all be called parasitism of some sort that's what i think and i'm also wondering whether or not a parasitoid wasps egg doesn't kill its parasite it doesn't kill its house but rather uh eats what it needs and then leaves and then the rest is okay the organism that's been half eaten manages to survive somehow because there are always gradations of these relationships that you can find if you look hard enough for them so um you know this is such a fascinating discussion to have on twitter it's very interesting and um i was worried because when i read this paper i um i have to admit i had the biggest problem with the names of the finnish islands i couldn't remember that exactly right no reason you should um and then i you know the overall picture i i get but i still find it confusing i'm not sure what the mechanism is and you know that's that's what i'm about but sure you don't always get a mechanism right but there's a wonderful uh general ecological uh niche to put this kind of study into and that's called island ecology oh yes absolutely so that's that's the that's another darwinism by the way yes darwin almost uh proved that creationism doesn't exist based on his study of volcanic islands that we're in various stages of population uh growth in fact uh david cuomin's book uh the tangled tree is all about island ecology right all of these naturalists going from island from from back then to the present sure and still doing it today yes um because it can be very i mean isolated islands are fascinating right because they're isolated and in that book he told the story of krakatoa right which yeah an island in the pacific that blew up it was a was a complete nothing left but a few specs and then it came back through volcanic activity and then years later it was completely full of life exactly plants seeds flew in and somehow birds got there and other animals you know animals can float on bits of wood long distances it's amazing absolutely right absolutely amazing the saltwater crocodile can swim 500 miles that's incredible and coconuts can float forever basically uh you know turtles can float long distances on their backs apparently they're they're happy daniel there's a plum island off the end of long oh yes there's a high containment laboratory there and between the island and the mainland there's plum gut which is very rough right and they say deer swim across it exactly there's actually a guy that's you know rotates who actually watches and they shoot the deer because they you don't want that so enough people know this but plum island is one of our biocontainment sites there's lots of stuff there that we don't want on the mainland and uh the deer potentially it's not a far swim i've sailed through there yeah and it's not a far swim the deer can swim back and forth but you don't want the deer going over yes getting something swimming back and in fact it's a it's a laboratory for animal pathogens not humans but like foot and mouth disease and that's right render pesticides avian influenza so they don't want the deer getting them and bringing them back to them yeah yeah exactly all right this rings a bell did you discuss that on twitch before i probably did i probably repeat myself all over you know no no i it just kind of rang a bill yeah well i used to go out there as a grad student i went out a few times to do some uh research on avian influenza and i remember on one trip the guy said you know we this is this island is here because this is a rough patch of water but even deer you can see deer just their head above the water swimming out that's right and so i didn't know they shot them but yeah it's a i'll tell a quick story and then we'll but uh so i grew up sailing and i'm about 19 20 years old and i have a not a big boat it's about 26 foot boat and i'm visiting my mother and the storm moves in and i'm supposed to sail from south long island through this stretch up to connecticut and it's such a bad storm the ferry isn't even running and i say to my mom you know i'm not sure about the weather today and she says daniel you're an excellent sailor i'm sure you'll be fine and so we try to sail through that the gut there the race at this when the tide is like going against us and we're barely moving the coast guard comes out sits off our stern watches us waiting for us to sink i think waves breaking over we finally eased our way through and then made it back into the sound cool plum gun it's a great name so you gotta wait till the tide is uh is slack and then you can swim across so daniel we're at 200 twips i guess you've run out of cases right you know this was this was tough because i had like you know i felt like uh what is that like the first day of school or something where you you want to make sure you pick a good one yeah and so i do have uh i do have a good one let me dixon you can't look you can't cheat [Laughter] so i was you know going over my head different ones but this seemed like a fun one so and i'm hoping that this one is a little bit easier that people will feel confident writing in so this is the story of a gentleman in his 30s and this man does have a several year history of hiv aids so he does have low cd4 counts and he presents with new onset lower extremity weakness headache and fever ends up in the hospital we get a little more history he reports that he lives with his wife and her cat he reports that he's supposed to be taking some medications but does not always remember to take them a little more into depth here past medical history so the hiv was diagnosed a few years prior to admission he has a cd4 count that is less than 100 he does have a detectable viral load doesn't report any surgeries no allergies his family history is non-contributory as far as medications again he's not very good at taking these but he reports that he was told to take a medicine every day one three times a week and one weekly he's currently out of work as mentioned he lives with his wife and her cat um substance use um he reports that because of his religion he does not drink alcohol and he only eats very well cooked meat as far as other exposures only local travel but he was born and raised in puerto rico in the in the big city he has had sexual multiple sexual exposures with multiple female partners over the years on physical exam he's following commands he's thin he's got a white coating a little bit on the sides of the tongue and the bucos bucal mucosa lungs are clear heart exam's unremarkable abdominal exam soft non-tender neural bowel sounds neuroexam he does have weakness in the lower extremities and there is some asymmetry to the exam his skin is unremarkable he has a number of labs done but i'm going to i'm going to give you i'm going to share with you the radiology we have a ct result i can see this and we have an mri result the ct shows multiple ring-enhancing lesions with surrounding edema he has an mri which is also showing multiple enhancing lesions okay i'm closing closing this so dixon can't pick something up just looking at that gave it away to you i didn't look at it okay but it gave it away for me so i said i don't need this i don't even need to see it i think no i don't either you know you sort of have it pictured in your mind like i think yeah i think i can i can just see it this is a very unreal man indeed yeah um so this man is hiv positive is uh but he has multiple female partners so do we understand we suspect that's where he acquired it and some of those encounters involved um monetary transactions if that's helpful okay got it um yeah and uh indeed yeah and uh so what i'm going to ask of our listeners a lot of people because this is this week and parasitism probably have a sense of what it might be but let's let's try to give the whole differential right because when we see a gentleman like this it isn't necessarily that one parasitic thing it might be something else as well so we want to be thinking about those does the coming from puerto rico does that does that matter and then how are we going to establish the diagnosis or are we good to go are there anything any blood work are you gonna do any therapeutic trials are we gonna do biopsies of his brain what are we gonna do at this point how old was he when he came from puerto rico so he came right when he was about 20. so he's been he had been in the states for over a decade gosh if you google ring enhancing lesions differential is like 20 different things so our uh so our email us should have a lot to think about this is one case daniel where i can't ask if hiv positive because you already told me yes all right very good um yes nixon i forgot to ask you if you had a hero it's okay yes i do yes i do so this is a a current person who i have deep regard for and uh have had the pleasure of working with in the past uh while he was a professor at tufts university's medical school in boston and his name is gerald kirsch k-e-u-s-c-h uh jerry kirsch uh his educational history involves a undergraduate degree at columbia university uh columbia college in those days and then uh an md degree from harvard university and then came back to columbia university as a postdoc or as a as a visiting um research physician to work in the laboratory of elvin cavett who of course and i you knew very well as part of our microbiology department and then um got his first appointment as a faculty member at tufts university and while he was there because we had met while i was at columbia also and we became good friends um he started to invite me to help him teach his parasitic disease courses and i can't tell you how much fun we had we um at one point he asked me to bring up some infected mice with triconella lawyer and adults and i did and we got the adult worms out and as some of you may know the adult female worm gives birth to live larvae and we had a microscope set up to witness the birth of the live larvae and uh only only only a parasite aficionado right yeah well we had the whole we had the whole class of medical students in this big lab and jerry and i were looking through the microscope at these larvae one at a time being born wow and as they were being born i would announce it's a boy and then he would hand somebody a cigar and he says oh it's a girl and then you'd had somebody else's cigar he he had a whole stack of cigars to hand out as the birth of this worm occurred over time it excited all of the students they all wanted to come and take a look at this every class that we taught during that week of intensified parasitic disease presentations was uniformly greeted with enthusiasm and attention no one cut class because they knew that not only would they learn things they would be entertained at the same time he then advanced his career by becoming the head of the fogerty center in washington d.c which proved problematic because of some politics involved in funding and the fogarty center was supposed to foster international cooperation between less developed countries and the united states with regards to infectious diseases his research interest was interestingly enough not parasitic but microbial microbiological he invented investigated shigella um shigella flexner as i recall and the toxins involved and how they affect the gut tract and that sort of thing but always passionate always attentive then later on became the i believe the research provost for boston university and at boston university he was solely responsible for getting the p4 facility established there so um which had a difficulty in opening and unfortunately i was unable to make the the twiv visit that resulted in some remarkable photographs of the twiv team dressed up in a p4 facility uh protection that's cool i missed that and i'm i regret for the rest of my life that i never participated but jerry and i have remained close i used to stay with him when i taught with him and he is such a gentleman and such a scholar and such a wonderful person and a caring and sharing person his children are all very very wonderfully educated and very alert and his wife is a pediatrician and she also is among those wonderful people that you really want to know and stay attached to so i uh i don't worship him as a hero but i know he is a hero to many other people i i don't even worship him i value his uh the friendship that we've shared over these many many years yeah i met him at the some at some opening ceremony for the the needle the boss the the p4 bso4 facility yeah very nice guy so we would tell jokes every now and then i must tell you the worst joke we told and we love puns and plays on words and um we at one point i i asked jerry whether he knew that there was this new designer birth control pill that came out and he said no i actually hadn't heard about that what's it called and i said it's called calvin decline we yeah okay fine we told jokes along those lines and we just we just had a lot of fun all right thank you dixon you're welcome that's it that's twip number 200. you can find the show notes at microbe.tv twit you can send your guesses for the clinical case and any questions or comments to twip microwave.tv and if you really like what we do consider supporting us microbe.tv contribute uh and this month this next two months parasites without borders fundraiser will go to support micro dot tv right daniel that that's the whole goal we got to keep paying the rent here on the incubator exactly yeah we got to get this chip on the wall put the light on the incubator so you can go to parasites without borders dot com and you make a donation and they will match it and we got our first donation we had a gentleman come by and actually hand deliver the first check of the fundraiser so this is exciting this is a destination if you want to come visit uh just let us know bring it bring a check that's great you have to be vaccinated though and yes this is true you have to have a mask this is true um dixon de pommier is at trichonella.org the livingriver.com thank you dixon oh it was an extreme pleasure 200 episodes you and i have done it together that's right we've been through the whole thing dixon and 200 more to come daniel griffin is at columbia university irving medical center parasites without borders dot com thank you daniel uh always a pleasure christina naula's at the university of glasgow thank you christina thank you for having me i need to get myself a website maybe you should do that everybody else seems to have one right i know i do have a twitter twitter handle but that's about as what is that you want to tell us what that is i think it is act christina one all in one word that christina nahula won all right now you're gonna get billions of followers you can find me at virology.ws i'd like to thank the american society for microbiology for their support of twip and ronald yankees for the music this episode that's not what i do at this point you've been listening to this week in parasitism thanks for joining us we'll be back soon another trip is sick oh we were in sync at least [Music] you

Channel: Vincent Racaniello

Views: 3,509

Keywords: parasite, parasitism, parasitology, Wolbachia, parasitoid wasp, gene flow, island ecology, spatiotemporal genetic structure, symbiont, trophic chain

Id: 5WQT35PNCSU

Length: 83min 2sec (4982 seconds)

Published: Sun Nov 07 2021