Case guesses:

Heather writes:

I’m no expert. I’m just a high school assistant principal who used to teach English (but who has loved science my whole life), but that sounds like pinworms to me!  

Raw pumpkin seeds are a folk remedy for them. I think the sample she gave her GP must have been in a part of the life cycle where they didn’t show up in the test.

You guys have been great friends to keep me company during this time of isolation. I live alone but I have subscribed to all of your “this week in” podcasts, and every couple of days it’s as though you’re having coffee at my table and I’m listening in on the most fascinating conversations. Thank you so much for that. 

Be well, stay well,


Anthony writes:

I am writing in once again to provide a possible diagnosis for the 60 year old woman mentioned in TWIP-181

The anal itching of course brings to mind  what is probably the most common roundworm parasite of humans – Pinworms!

Of course however, they are extremely small and would probably not be video worthy and would not likely persist as a smoldering infection for so many years – this leads me to my possible explanation of what was seen on the video – A mobile segment of a tapeworm! Of course if it is indeed a flatworm foe PZQ is the usual drug of choice.

If I indeed do win a hardcopy I would like it to shipped to a lab rental serivce/diybio teaching facility in NYC called genspace! Even though it is only a BSL1 facility that does not mean that people do not work with closely nonpathogenic organisms and thus could be an interesting read for those waiting on a PCR run!

Once again thank you for all you do!


Self taught biochemical maniac 

Steve writes:

Hello TWIP team,

It’s been quite a while since I replied to a case study–I got behind on episodes and couldn’t keep up!

This one is pretty straight forward.  Our 60 year old woman from Lima likely has Enterobius vermicularis, also known as pinworm infection.  The adult females tend to come out at night to lay worms on the anus.  A side effect of this is intense itching.  Scratching it can cause the eggs to get on the fingers, allowing for reinfection via the good old fecal oral route.

This is much more common in young children who constantly scratch their rears anyway, and aren’t known for having even the poor hand hygiene habits most parents have.  This is also likely how she was infected–I suspect she has young grandchildren around who are infected themselves.

Not surprised that the stool culture and ova and parasites exam came back negative–I had to advise a Nurse Practitioner a while back on an adult patient that O&P exams often miss pinworms, and that the best test is placing clear tape on the anus first thing in the morning after the pinworm has laid her eggs and then looking for the eggs under a microscope.  We have sticky paddles that work even better, but we tend to send these to a reference lab now due to the fact that it’s so rarely ordered it can be difficult for our techs to retain competency at identifying pinworms, and even the pediatric physicians have stopped performing it as a PPMP here.

Albendazole or mebendazole treatment will solve the problem, but even without medication she would likely see the problem resolve in time so long as she doesn’t reinfect herself.  Might be worth having the grandkids examined as well.

Thank you for all you do, stay safe in this pandemic era!

Steve in the Eastern Sierra.

Elise writes:

Dear TWIP Trifecta, 

Here I am, a blast from the (surely) forgotten past writing to you. I have been a loyal follower of TWIP and TWIV for years, but life caught up with me and I have not been able to write in with a diagnosis for so very long. Now, however, that I am “sheltering in” in lower Manhattan, I have a few patches of extra time that were not previously available to me, so here I am. (It is 61 degrees F. 16 degrees C and pouring today.)

I think that Dr. Griffin’s patient has returned from her travels with a pinworm infection (enterobiasis)  back from her travels to Kenya. She recalls  quite vividly having the same nighttime anal itching that she has now as a child in Peru and mentions that her mother gave her pumpkin seeds to cure it. 

Pumpkin seeds are apparently a home remedy for several types of gastrointestinal worms (in addition to pin worm,  they have been used  in an attempt to get rid of tape worms). There is some evidence that cucurbitacin, a compound in pumpkin seeds, among other plants (bitter gourd also contains this compound, for instance) does help eradicate gastrointestinal worms, though tests on livestock have used pumpkin seed extract, which presumably is much more concentrated than what could be obtained by eating normal human amounts of pumpkin seeds. (But maybe this is not the case if the remedy worked for the patient as a child.)

Dr. Griffin didn’t post the video that his patient supplied, I suspect because it would give up all the evidence we would need. Pinworms migrate at night to deposit eggs, so it is possible the patient captured a pinworm in the act of wandering around. That evidence combined with the extreme anal itching makes that a likely diagnosis.

The CDC, not endorsing the pumpkin seed cure, recommends mebendazole, pyrantel pamoate, or albendazole in two doses separated over two weeks. 

Thank you so much for giving non-scientists a chance to try our hands at guessing. 

Finally, I can’t thank you all so much for everything you do. Dr. Despommier, you brought tears to my eyes as you talked about what a hero Dr. Griffin is. You are all heroes to me. I so appreciate everything you do, especially now when it is easy to feel lonely and without hope. I tune in to TWIP or TWIV and feel interested and galvanized and engaged, and in this moment, that means so very, very much. 

Huge thank you to all of you. Be well, be safe and best, best wishes

Elise in Lower Manhattan 

Adil writes:

Dear Doctors,

It is currently a cloudy 42 degrees (6 C) in Cleveland. I hope you are doing relatively well in the midst of the current situation; one silver lining of which has been the ability to listen in a timely enough manner to start responding to cases again. My case guess is pinworm given the location of the discomfort. This was reinforced by the finding that pumpkin seeds are a long standing treatment for that parasite though I can not find credible evidence of efficacy. I also wanted to inform you that work I wrote regarding TB and soil based helminth co-infection in South Africa was accepted by the Pathologist as they start up their rear on infectious disease. Thank you both for the wonderful family of podcasts and for motivating me. I already have both a copy of Parasitic Diseases and Red Mother so I hope someone else can experience the joy I already have. My best as always.


Adil Menon 

CWRSOM MD Candidate 2021

Pathology Interest Group Leader ’18-’19

AMSA Global Health Leader  ’18-’19

Trudy writes:

Dear TWiPers,

I may be fairly proficient in virology, but when it comes to parasitism, I really only know one thing: pinworm (Enterobius vermicularis). 

Best Regards,


P.S. I already own a copy of Parasitic Diseases

Adam writes:

Hello fellow eukaryotes,

I am writing in to TWiP for the first time for the episode 182 case study. When I heard the anal itching, I immediately thought pinworm (Enterobius vermicularis). That was further confirmed by the negative O&P and q-tip result since Enterobius doesn’t come out in stool.

She probably picked it up from her grandchildren in the US. The travel to Uganda is a red herring- in fact, it seems pinworm may be less prevalent among Ugandan schoolchildren than among US schoolchildren. I attached a 2001 article “Epidemiology of Intestinal Helminth Infections Among Schoolchildren In Southern Uganda” which reports 1.7% prevalence (35 cases / 2004 children). Similar studies in California in the 80s found 7-43% prevalence among schools. I wonder if it’s possible that pinworm prevalence is lower in Uganda due to competition from the numerous other helminths listed, though I don’t recall any of them specifically competing for resources in the anal + perianal region.

I also want to echo Dickson’s praise of Daniel on the last episode. I am amazed that you managed to get in another great episode of TWiP along with all of your work on treating COVID patients and your interviews on TWiV.


– Adam

Josh writes:

Hi TWIP hosts

I believe Dr Griffins patient has Enterobiasis, commonly known as a pinworm infection. What lead me to this assumption is that she was suffering from pruritis ani or an itching sensation around the anus occurring nocturnally, a characteristic symptom of  Enterobius vermicularis infection. Whereby the gravid females lay their eggs around the perianal area during the night subsequently leading to the itchy sensations. Why this occurs nocturnally is believed to triggered by the hosts drop in body temperature during sleep. Another important clue was that her ONP stool culture came back negative, this is likely due to how quickly the eggs hatch and the larvae may crawl back into the anus (retro-infection). Therefore in order to obtain the eggs (for diagnosis) a clear adhesive tape should be applied to the perianal area in the early hours of the morning before a stool has been made. Finally, Dickson’s emphasis on whether she had grandchildren also gave it away, as this is a common infection among young children and institutionalized people (daycares). I believe the video is most likely going to be an extraction of a adult female (8-13mm long). What is interesting is that her husband isn’t complaining of the same symptoms but the bedding is most likely harboring the infective eggs (can last up to 2-3 weeks on inanimate objects) or be inhaled (as they can be go airborne). I hope I’m right. 

PS. It’s a sunny, windy-less 24°C afternoon from Cape Town, South Africa, looking forward to more TWIP and TWIMs. I know this isn’t TWIV but here is a recent paper from nature that sparked my interest and maybe yours: “Dynamic genome evolution and complex virocell metabolism of globally-distributed giant viruses.”

This paper left me wondering could there be viruses that are inserting genes (beneficial/detrimental) into our potential offspring’s genomes by targeting our germ cell precursor or cells of spermatogenesis or oogenesis? 

Kind regards


Josh Aaron 

MSc Microbiology student (Stellenbosch University)

Dan writes:

Hello TWiP, 

I’m Dan from Connecticut, quarantined at home due to Corona. I’ve listened to TWiV once in a while before, but I’m using the time now to work through the other MicrobeTV podcasts. Thanks to the whole team for putting together such interesting content!

My guess for the TWiP 182 case is: Enterobius vermicularis, the human pinworm. This little bugger seems to match the description closely and Dickson’s question about children/grandchildren supports this, since school-aged children are those most affected. Treatment is two doses of the microtubule depolymerizing special (mebendazole or albendazole) or pyrantel pamoate given two weeks apart. 

Anyways, I’m no doctor but that my guess. Thanks again TWiPsters! I’ve learned so much from the show. 



James writes:

I’m going to guess that she has some grandkids or foster kids or kids in an orphanage she supports or something similar, that ALSO have “itchy butts.”

The classic one would be Pinworms (Enterobius vermicularis.) Very common in US and elsewhere. Pumpkin seeds are a home remedy, but I could not find (quickly, since I’m in the midst of teaching Microbiology to Med Students!) anything up to date. 

I considered, very briefly Schistoma mansoni which could get into colon–but I don’t really know if it causes pruritis ani. I did find a brief mention of a perianal rash with Schisto.

This might be sucking up just a bit, but Trichinosis can cause pruritis. And since I attended Duke Medical School sucking up was a valuable survival skill!

Not sure how I avoided pinworms with three daughters and 4 grandsons. I got Giardia from my oldest daughter who got it at a girl scout camp in the mountains near Las Vegas of all places. 

As always, what is the differential diagnosis? ‘Rhoids! Probably #1. Ask ANY woman who has delivered any babies vaginally. Fissures could do it. I found that some spicy foods can do it–I ate some five alarm eggplant dish in India when I was 18; I don’t know if it was chemical or E. coli, but man did I get the trots and I had “anodynia.” Just made that word up, but it sounds good doesn’t it? Also looks like chronic wetness and post-antibiotics (Candida, ALMOST a parasite right? It has a nucleus!) 

So TWIP on and draw my number…


James M. Small, MD PhD

Associate Professor of Pathology

Rocky Vista University

Andrew writes:

Kia ora from Pongaroa,

No book won yet – I am hoping for a fluke (shout out to Dixon in TWIV 603)

Weather: the Pongaroa drought has broken and today there is a strong wind, clear skies and a temperature of 19°C.

Covid-19: Today is the first day of the relaxation of our strict shelter in place measures and apart from some businesses being able to start up again if they can provide “contactless” delivery, like pizzas life, will be much the same as it has for the last five weeks – everyone staying within ‘bubbles’ of households and/or essential workers and avoiding other people and keeping 2 meter distance at any encounter. Our active case tally is 270, down from 929 and daily new cases are in the single digits – mostly Kiwis returning home. Testing and tracing have resulted in an R0 estimated to be 0.5 or lower. Our Prime Minister, Jacinda Ardern, is keeping the country in strict isolation, with only New Zealanders being able to enter and she has a staged and gradual plan to return us to whatever the “new normal” will be like – hopefully a few weeks away. She has the strong support of 86% of the country – we are rather proud of her.

My guess: Pin Worm Enterobius follicularis

I think Daniel is being tricky here including a couple red herrings to lead us off the track. The lady’s age and the travel to Uganda can be seen as less important than the facts that our parasite can happily stay on the end of a q-tip and that a video was taken means it was most probably motile. The only other parasite I can think of, small enough and can cause intense itching, is sarcoptes scabiei which would be too small to be easily noticed on the cotton bud. So unless she has a pet that has whip-worm the most likely vector are her grandchildren. Incidentally, I grow pumpkins and my neighbour constantly asks me to give her any spare pumpkin seeds to de-worm her chickens another good clue. 

Ka kite anō (kah keet-ay ahn-aw) (see you again),


Samantha writes:

Hello TWIP hosts,

I would normally be writing from the beaches of, I mean, the medical school library in Miami, but, alas, I am writing from Nevada where I am currently studying from home with my family. Thank you for all that you do in terms of scientific communication during this time (and all other times, too). 

My guess for this week’s case is Enterobius vermicularis- aka, pinworm. The anal pruitis, and finding of the adult female during her nightime migration down from the colon or rectus to the perianal skin to lay her eggs is indicative of this pesky worm. She likely picked up the eggs from her grandchildren, who may have had the infection, scratched their butts, then deposited the eggs on objects, people, and toys in the room by not washing their hands, as kids do (or, do-not). I looked into pumpkin seeds, the seeds of Cucurbita pepo, as an anti-helminth and found that seeds/flesh/leaves of the Cucurbita plant been long been used in traditional Native American medicine as antimicrobials, to treat urinary incontinence, and even to lower blood glucose. It seems that much clinical research has been conducted to investigate various compounds derived from the Cucurbita plants for a wide range of pharmacological interventions. Very cool; nature provides.

To treat this patient, prescribe 11mg/kg (max 1 gram) pyrantel pamoate in a single dose, followed by a second dose 2-3 weeks later to kill any worms that had hatched from eggs ingested following the first treatment. I would also provide the same treatment for the child and anyone living with the child or who has close contact.

One final note, I think I must have been reading about pumpkin seeds too long, because when I referenced the Enterobius section of Parasitic Diseases, the first thing I thought of when I saw the picture of Enterobius eggs was “wow, those look just like pumpkin seeds!” With their shells intact, they kind of have an egg-like morphology, maybe a crossover of an enterobius and trichuris egg, just giant. 



Grzybek, Maciej et al. “Evaluation of Anthelmintic Activity and Composition of Pumpkin (Cucurbita pepo L.) Seed Extracts-In Vitro and in Vivo Studies.” International journal of molecular sciences vol. 17,9 1456. 1 Sep. 2016, doi:10.3390/ijms17091456

Salehi, Bahare et al. “Cucurbits Plants: A Key Emphasis to Its Pharmacological Potential.” Molecules (Basel, Switzerland) vol. 24,10 1854. 14 May. 2019, doi:10.3390/molecules24101854

Parasitic Diseases, 7th Edition 

Kevin writes:

In order to avoid coarser terminology I will state, perhaps over-delicately, that our patient has pruritis ani. I love definitions that leave the hearer completely unenlightened. It reminds me of old Latin dictionaries that define sex acts with Greek instead of English. 

Our case reminds us that biology can be degrading. Nature, it its infinite perversity, afflicts some people with a type of intractable itching called neurodermatitis. Naturally it targets the scrotum and vulva. A conspiracy involving dermatology, Sigmund Freud and the demiurge. 

Our case also reminded me of a schoolyard jibe in the form of a query and response, from the early 70s; it was directed at someone who was scratching his posterior (perhaps a patient similar to our TWiP 182 patient):

Q. Are you going on a bus trip?

A. No.

Q. Then why are you picking your seat?

It is no coincidence that the anatomic zone at the seat of our discussion was formerly referred to as ‘the fundament’. The psychic power of this lowly location has been used as a whipping boy by figures as disparate as Luther and Freud. I close these generalities with a quote by historian and legal scholar William Ian Miller: “By virtue of this extended metaphorization the anus is seen as the footing on which our dignity depends. It must be secured or everything else built upon it crumbles.”

I don’t think that pumpkin seeds are cutting it. (More on those below). I strain to construct a differential diagnosis. Here’s one: perhaps an incidental infection with rat oxyruids (Manson’s Trop Dz 1923…Syphacea obvelata). 

Our patient is suffering from recurrent symptomatic Enterobius vermicularis infection; pinworms. PD7 dramatically phrases the worm’s birthing style: “…she experiences a prolapse of the uterus, expels all her eggs, and then dies. Expul­sion can be so intense that the eggs become airborne.” Biology and life cycle are succinctly treated in PD7. Other interesting facts from various reviews: 

  • Very common. European surveys show infection rates of 18-34% in school age children.
  • Treatment usually to be repeated in 7-10 days due to unreliable egg killing. Whole family as well as sex partners need to be treated.
  • Six hour embryonation is among the fastest of any nematode.
  • Ova can survive in the environment for 1-3 weeks.
  • 30-40% of infected patients may be asymptomatic.
  • NOT ZOONOTIC. humans are the sole host. No risk from pets.
  • Stool O & P will be negative. The eggs are laid outside of the intestine. The eggs are not reliably found in stool specimens. Need to perform classic transparent tape test.
  • No visceral migration stage of the worms (as in ascaris).
  • Complications such as ectopic worm migration (eye, kidney etc) are rare.
  • Vulvovaginitis / female genital involvement possible. 
  • Appendicitis associations are debatable.
  • Most reviews stress the psychological stress and misery caused by these infections.

Treatment recommendations in PD7 importantly discuss some absurd price disparities between various treatments. Manufacture of the old standby drug mebendazole has been discontinued and prescription albendazone can cost 10-15 times more than the OTC pyrantel pamoate. Also, pumpkin seeds (curcurbita) as a vermifuge aren’t as far-fetched as they sound (references and discussion in the endnotes.)

Where can I see that video that Dr Griffin mentioned? Appreciate the whole TWiP group’s superhuman efforts during our pestilential era.



Wendt S, et al. The Diagnosis and Treatment of Pinworm Infection. Dtsch Arztebl Int. 2019;116(13):213‐219. OPEN ACCESS (Wendt cites Despommier et al (PD 195) in their references. )

Wendt et al from Leipzig spare no detail in their enumeration of risk factors: unchecked anus-finger-mouth contact, independent and unsupervised personal hygiene practices, in addition to poor hand hygiene….

Friesen J, et al. Detection of Enterobius vermicularis in greater Berlin, 2007-2017: seasonality and increased frequency of detection. Eur J Clin Microbiol Infect Dis. 2019;38(4):719‐723.   states that 30% of infections are mild and asymptomatic in one third of cases.

Rudko SP, et al. Enterobius vermicularis as a Novel Surrogate for the Presence of Helminth Ova in Tertiary Wastewater Treatment Plants. Appl Environ Microbiol. 2017;83(11):e00547-17. Published 2017 May 17.kind of a gross out. ….this ‘buoyant ova’ is incompletely removed, even through tertiary treatment…WHAT AM I DRINKING??

Purohit G, et al. Inadvertent detection of massive Enterobius vermicularis infection in an asymptomatic adult with rectal blowout following barotrauma. Ann Parasitol. 2019;65(1):103‐105.   One-day history of barotrauma per anum, specifically reported as, playful insufflation of air through a gas pump cylinder inserted into the rectum by his co-worker. Laparotomy showed a large number of small white worms throughout the abdominal cavity. Rectal blowout articles aren’t as uncommon as you might think. 


“In female patients, the larvae that hatch on the skin near the anus occasionally crawl into the vagina instead of the rectum, establishing an aberrant infection. Less frequently, gravid parasites infect the fallopian tubes. Aber­rant infections also include pelvic peritoni­tis, ovarian infection, and granuloma of the liver.” Wendt.

Other complications:

  • Eosinophilic enteritis
  • Appendicitis
  • some evidence that Dientamoeba fragilis can be carried w/i the eggs of E vermicularis. –mentioned in my notes for TWiP 177. 

associations with acute appendicitis are still debated., general belief seems to regard this as rare…

Akkapulu N, Abdullazade S. Is Enterobius vermicularis infestation associated with acute appendicitis?. Eur J Trauma Emerg Surg. 2016;42(4):465‐470. Results: Enterobius vermicularis was detected in the appendectomy materials in 9 of 1446 patients (0.62 %). Histopathologically, only one of nine patients had acute appendicitis while the others were diagnosed with lymphoid hyperplasia. There were no statistically significant differences between the groups except WBC count. However, the WBC count was significantly (p < 0.05) lower in the group which was detected E. vermicularis. 


Pumpkin Seeds. Do They Control Worms? Delaware State University Cooperative Extension Programs.Dr. Dahlia Jackson-O’Brien, May 2010

reports on a study of n=22 goats. Some preliminary positive results when the seeds were given as a drench (medicine forcibly administered to an animal). 

Grzybek M, et al. Evaluation of Anthelmintic Activity and Composition of Pumpkin (Cucurbita pepo L.) Seed Extracts-In Vitro and in Vivo Studies. Int J Mol Sci. 2016;17(9):1456. Published 2016 Sep 1. OPEN ACCESS  A mouse study…two model nematodes: Caenorhabditis elegans and Heligmosoides bakeri. Conclusions: Pumpkin seed extracts may be used to control of Gastrointestinal (G.I.) nematode infections. This relatively inexpensive alternative to the currently available chemotherapeutic should be considered as a novel drug candidate in the nearest future. 

Díaz Obregón D, et al. Estudios preclínicos de cucurbita máxima (semilla de zapallo) un antiparasitario intestinal tradicional en zonas urbano rurales [Preclinical studies of cucurbita maxima (pumpkin seeds) a traditional intestinal antiparasitic in rural urban areas]. Rev Gastroenterol Peru. 2004;24(4):323‐327.  It was found that the MIC of 23 gr. of pumpkin seed in 100 ml. of distilled water can produce an antihelminthic effect. This concentration is equivalent to +/- 73 pumpkin seeds (x2 = 5.6, p<0.01


Authors of PD7 to be congratulated on discussing the absurd price of pinworm pharmaceuticals. This valuable information was not in any of the general enterobius articles that I reviewed.

$6.58 at CVS (

a single 200mg tablet of generic albendazole=$42.00, non-generic (Albenza) =$114.00

the generic albendazole, as stated in PD7 more expensive by a factor of TEN…GoodRx price quote (cheapest)= $75.00 and as high as $183.00

Mebendazole is available in the United States only through compounding pharmacies. (CDC website)

curcurbita maxima seeds (Amazon) 200 seeds = $3.99 (vendor ZLKING)

From the Consumer Reports–Pinworm Treatments Are an Expensive Drug Mistake You Don’t Need to Make (01/27/2017)

“When Cheryl Kennedy of Chicago went to fill a pinworm prescription for her 4-year-old daughter, she was astounded to learn that four tablets of the drug Albenza cost almost $700—even with insurance.”


1.  from 04/28/20:   “Canine angiostrongylus is a life-threatening disease of dogs caused by a very sophisticated worm.”

Who is this champagne quaffing, tasseled-loafer wearing, manicured, avocado toast nibbling vermiform creature?

2. The tortured terminology of the butt crack:   How does one describe this negative space that is nary a space at all? There are many choices:

gluteal fold

natal cleft (the furrow between the buttocks)

gluteal crease

gluteal sulcus

fold of the buttock

intergluteal cleft

cluneal (also clunial) cleft…L. clunis buttocks, haunch, hindquarters

bum crack

fanny crack

This anatomical area defines the phenomenon commonly known as ‘plumbers butt’.

3. Historic anecdote.  I personally suffered from pinworm infection in 1974 at the University of Illinois in a co-ed dormitory. Yes, they performed a transparent tape test. Many people had were infected. It was very memorable and extremely distressing. The pests do cause insomnia. The health service provided a big single tablet of mebendazole. It worked. I wasn’t re-treated to the best of my recollection. I’ve been eating pumpkin seeds ever since. 

Devlin writes:

Hey TWIP team,

I discovered a few weeks ago when I stumbled upon a TWIV episode. Being a bored quarantined high schooler with no job, little homework, and an interest in microbiology, I got hooked. I’ve been mostly keeping up with the latest stuff, but I’ve listened to few older episodes that really interested me, most notably the TWIVs on delta viruses and non primer dependent DBDPs.

I know I am at a bit of a disadvantage here, competing against PhD students when all I have is a class of 2020 yard sign and no high school diploma, but I think I’ve got it. The parasite is likely the pinworm. These parasites spread via the fecal oral route, catching a ride on people’s fingernails. Once digested, the pinworm hatches and develops. It lays its eggs in the rectum, causing itchiness. Beyond this, their disease is relatively asymptomatic and they cannot be identified in stool samples. One way to identify them tho, is the eggs are visible under a microscope. I believe the q tip either got some of these eggs or an unlucky mother. I am not sure about the Uganda part, but I think my idea is worth a shot.

One question I have is about past episodes. I was wondering if any scientist from my city (UW/Fred hutch) or the college I will attend (Colorado College) have gone on and what episodes those were. I’ve heard the hosts talk about Harmit Malik a few times, and I was actually able to interview him a few years ago for a school project about migrants. Another episode I would be curious to listen to is one about bacteriophages epidemiology. I know it’s a very specific topic interest, but I feel like it would be something very interesting to listen to. 

Best wishes and thanks for all the podcasts,


Cecelia writes:

Dear Doctors,

  I will be brief because I’m sure you will get plenty of responses for this case study. I believe the 60 year old female patient is infected with Enterobius vermicularis.

  According to PD 7 it is the most prevalent nematode infection. 

  The patients ova and parasite studies would be negative because the eggs are laid at night in the perianum  by the gravid female when she migrated out of the anus. These eggs can be seen on a scotch tape prep or a pin worm paddle. 

   The specimen must be collected early in the morning before the patient gets out of bed and goes to the bathroom.

   The patient was was probably able to collect some of the worms inside the anus with a q tip. I hope you all remain safe.



Saint Petersburg,Fl.

Schuyler writes:

Good morning,

I hope you continue to be well. No book last time but at least my first ever guess was right! Thank you for clarifying about human vs. canine scabies – since both diseases are called scabies and vets always told me it was contagious, I just assumed it was the same mite. This served as a reminder that it is dangerous to assume. 

My guess for the 60 yo female from Peru is pinworm. If something visible can be extracted from the anus and it is neither a human-inserted foreign object, nor so-called “rope worms” (sloughed-off intestinal lining due to the consumption of a consumer-activated bleach known as MMS), then it is most likely a worm. I found a paper looking at the toxicity of pumpkin seeds as they are, apparently, a folk remedy for stomach pain, inflammation, fever, and, most relevant, worms (Cruz et al., 2006). Intense peri-anal itching combined with negative stool sample suggest pinworm. According to the CDC, pinworms exist worldwide, so I won’t try to guess whether she got this case from Uganda, Peru, or the good ol’ USA. Tape test to confirm diagnosis. I would check the grandchildren too since pinworm is rather contagious.

Wishing you the best. Thank you again for this wonderful podcast and for all the work you continue to do. I pray for your safety and urge all listeners to stay home, even if they live in a state that has opened up, unless mandated to work. 

Stay safe,

Schuyler (pronounced “Skyler”, she/her/hers)

[1] Cruz et al., 2006:[2] CDC page on pinworm: