Sara writes:

Hello to the Twip quadfecta, from a frigid (32F, 0 C) evening in Philadelphia!

It felt like an eternity waiting for last episode (but I understand given how busy you were with TWIV). Thank you so much for describing how overfishing could affect parasitic worm to fish ratio in the ocean! Absolutely fascinating to learn about the ecology!!

I’m apologizing in advance for the length of this response. After the last episode, I resolved to shorten my answers.  But then this case presented several problems for this gentleman. I feel terribly for this patient — what a miserable bundle of health issues! I am happy that he could benefit from Dr. Griffin’s care! I hope he recovers.

This  is a 60-year-old gentleman who presented with three months of polyuria, polydipsia, and weight loss of unspecified amount, followed by an eruption of an extremely pruritic rash on his abdomen, finger beds, and on his elbows (we are not told whether flexural surfaces or on extensor regions but I’m guessing flexural) that subsequently spread to his household members. Next, he developed a week of fever, headache, and cough followed by dyspnea which prompted him to seek medical attention. Upon admission, he was hypoxemic to 85% on RA. He lives in crowded conditions within the refugee camp where he is located in Bangladesh. He has a heavy smoking history, is HIV negative, works as a shopkeeper (and therefore is exposed to others often).

Lab studies we are given are limited to leukocytosis and hyperglycemia to 300mg/dL. We don’t have a CXR or respiratory viral panel. I wish I could know whether there was any blood in his cough. There was no mention of diarrhea. If he had hyponatremia that might point toward Legionnaire’s disease (though I didn’t hear about camp-wide air conditioning units full of water for amoeba to swim around in endosymbiotic relationship to Legionella pneumophila) .

 This may be an example of “true, true, and unrelated” or I’m about to learn about a parasite I haven’t heard of!

 Newly diagnosed diabetes mellitus

Common things being common, someone with several months of polyuria, polydipsia and weight loss who is found to be hyperglycemic to 300mg/dL on random fingerstick has diabetes. Appropriate glycemic control will be important to prevent further infectious complications in the short term and renal, microvascular, and retinal complications in the long term. Stopping here to try to keep my answer from becoming a tome.

 Pruritic Rash

The incredibly itchy rash, itchier at night, that spreads to his household is probably caused by Sarcoptes scabiei.

This mite burrows into the skin to lay eggs, is highly active at night and causes severe itching in most people.  I would look for the classic burrows between his fingers using a dermatoscope if one were available. I might consider taking some shavings from his skin to examine under the microscope although I remember an attending teaching me that this is very low-yield given that the mites travel vast distances on the skin and the mite per skin centimeter load tends to be rather low in individuals who aren’t immunocompromised (compare with crusted scabies that can develop in people who have compromised immune systems and thus a high mite burden). If I saw the burrows, I’d be comfortable treating him and his family with permethrin (over all skin, no need to put it in the hair) with a coordinated effort to put any bedding, clothing, or other items they had touched under direct sunlight and not touch it for 72 hours or wash and dry everything at high heat which I am not sure is an option in their camp. The scabies mites can only survive for 72 hours without a meal so I do think that quarantining their household items for 72 hours without touching them and treating the entire household during that time would do the trick (is this true?).

Other causes on my differential in order of decreasing likelihood: (1) tinea corporis is second most likely, (2) contact dermatitis from any number of irritants in the household is possible but the spread of the rash to all household members makes this likely as does the nighttime itch component, (3) body louse which are visible to the naked eye and would be unlikely to cause itching between the fingers; (4) bed bugs which can cause the entire family to itch and are common in crowded living conditions; however he would have complained of bites rather than a rash, (5) The location of the rash between his fingers led me away from an allergic reaction to an intestinal parasite. Cutaneous larva migrans would not present in the distribution of his rash so it’s off of my differential.

Finally but most urgently, his respiratory infection

I know this is a podcast about parasites, but given that Dr. Griffin was consulted on this case during a global spike in covid infections and given that the patient lives in crowded conditions that preclude safely distancing oneself from the pandemic, I’m primed to think that they are dealing with a covid outbreak in the camp. Fever and headache followed by subsequent cough and dyspnea certainly fits the bill for a covid pneumonia (to which his newly diagnosed diabetes mellitus predisposes him).

To avoid the availability heuristic, he could have many other respiratory viruses including influenza A/B or a novel influenza virus, parainfluenza, human metapneumovirus etc…   I’d start with a chest x-ray and a respiratory viral panel. I would also collect sputum cultures and consider meliodosis which would grow as well as legionella. Given his crowded living conditions in TB endemic area, would have to rule out TB (3 sets of acid-fast stained sputum) which could reveal non-tubercular mycobacterial infections which tend to be more subacute in presentation.  In his region of the world the dimorphic fungus talaromyces with its bright red pigment (I think of red high heels “talon”) can infect immunocompromised hosts, but I don’t think he is immunocompromised.  I wonder about acute pulmonary histoplasmosis.  If he were in the southwest of the US, I would also consider acute pulmonary coccidiomycosis which can present in a flu-like fashion. Acute pulmonary blastomycosis if he were on the eastern portion of the US and Canada.

My guess though is covid.  I really wish I could think of a parasitic cause. If he had diarrhea, more chronic symptoms and bloody cough I’d say Paragonimus.

This show makes me ridiculously happy. I’m so very grateful to you for making it! I learn so much from you and am so happy for the opportunity to learn near the beginning of residency!

Looking forward to next episode,

Sara, MS4

Jen writes:

Hello TWiP team!!

  I am a HUGE fan of all things TWIX! Thank you for this excellent  Podcast! I really enjoy listening  on my days off from working as  a Pediatric RN when I spend my free time making  art!

Weather report here in Rhode Island is Sunny with a temperature  of 33 degrees Fahrenheit.

Here is my guess for this week’s case study:

The patient is a 60 yo male living at Rohingya Camp.

 The gentleman’s  sx’s  began 3 months prior to seeking medical help. He reported being up at night with increased urination, Increased thirst and weight loss. Upon exam his blood glucose was elevated. These symptoms  along with the weight loss and blood glucose level would strongly  indicate diabetes. Therefore  Diabetes is my first diagnosis.

   Secondly the rash. The patient reported itchy rash all over especially  on the hands, also contagious  to the rest of the household members. I would love some more information  about  this rash and really would like to see it, but based on these symptoms  and the suboptimal  living conditions, my guess would be scabies.

   Third diagnosis, the dyspnea. This gentlemen started with symptoms the week prior to seeking help. His symptoms were reported as fever and headache, followed by cough and difficulty breathing with O2 Sat’s in the 80’s. These symptoms would seem to indicate a respiratory  infection. It was also reported that there was some kind of respiratory  illness in the community.  I would strongly suspect Sars-CoV2/Covid.

Those are my guesses it’s  a trifecta: Diabetes, scabies, and covid. I hope that he has recovered from the covid and the scabies and is able to access all that he needs to treat his Diabetes. I can only imagine that being difficult in the Rohingya Camp. I wish I could do more to help.

              Thanks for all that you do!!


                                        Jennifer Fallon

PS: Christina, I love your background. The crochet is beautiful!! I would love to hear about it. It seems to be growing!

Patrick writes:

Dear TWIP,

I am writing from Southwestern Ontario, Canada, where it is: overcast, 75% humidity, minus 15 celsius (5 fahrenheit), and with minimal wind  – not too bad for late January. I write in as a long time listener but first time hopeful diagnoser. I have no connection to the medical or research community, save as a very occasional patient; working instead in municipal planning and natural hazard management (specifically flooding and erosion).

Nevertheless, I am an unabashed parasite fan, of the trematodes especially, and have been variably entertained and enlightened by each of you. Thank you so very much for all that you do.

As for the case of 60 year old gentleman from (or adjacent) the Kutupalong Refugee Camp described in episode 202; such a setting leads one to imagine a staggering number of potential ailments, but here it goes:

The initial set of symptoms seems consistent with uncontrolled diabetes (frequent urination, weight loss, thirst and the later high glucose detected). Anything urinary makes me think of chronic infections by Schistosoma haematobium, but the geographic region is suspect, and one would think other symptoms such as haematuria would have presented.

The later respiratory symptoms make me immediately contemplate Paragonimus westermani, but something more likely (and timely) such as the SARS-CoV-2 virus or variant, or the repercussions of a heavy smoking habit seem more likely. The relatively sudden onset of respiratory symptoms in conjunction with fever and feeling otherwise poorly makes the acute cause more probable. P. westermani exposure also seems somewhat unlikely based on location and presumed local scarcity of drunken crab.

My first thought regarding the rash is scabies (Sarcoptes scabiei var.), noting the intensely itchy rash in many locations, including between the fingers. Crowded living situations and household contact provide a ready setting for scabies to be transmitted, and the refugee camp no doubt qualifies. The household suffering the same rash is consistent with a scabies infection. The high WBC could be attributed to this, or another simultaneous infection.

Lacking any other apparent GI symptoms, I therefore conclude this man is suffering from an unfortunate combination of recent SARS-CoV-2 infection (or similar respiratory infection), suffers from uncontrolled diabetes (itself possibly viral induced), and the rash – which is isolated from the other symptoms – is scabies, the disease-causing parasite in question.

Thank you again, I look very forward to hearing what the actual diagnosis is. Warm wishes from Canada.


I find non-human parasites and parasitoids equally fascinating, and who could fail to be enthralled by the ingenious parasitoid wasps who co-opt their victims nervous system through use of a virus, a virus which I understand is actually coded in the wasp’s genome (please correct me if I’m wrong)? This leads me to wonder: Are you aware of any significant human parasites known to consistently harbor (or even generate) one or more viruses that subsequently infect the human host?



Alex writes:

Dear Hosts,

The patient is exhibiting symptoms of diabetes mellitus, including polyuria, pollakisuria, nocturia, weight loss and elevated glucose. This might have predisposed him to develop a more severe course of disease than the rest of the family, who only have dermatological manifestations.

While a hypoxic patient with fever and malaise must nowadays raise suspicion for COVID-19, the elevated WBC count is not typical. If these WBCs are neutrophils, I would first consider a bacterial pneumonia, but eosinophilia would be indicative of Löfflers Syndrome secondary to S. stercoralis hyperinfection as a consequence of immunosuppression in the context of de novo diabetes mellitus. While Ascaris can also cause Löfflers, it is not usually associated with a rash.

Treatment is with ivermectin and supportive oxygen, antibiotics with efficacy against gram negatives may be considered, as the Strongyloides larvae often translocate gut bacteria on their journey, which can cause peritonitis. Afterwards, the suspected diagnosis of diabetes should be evaluated and treatment initiated if necessary. Best regards,


from Vienna, Austria

Druti writes:

Dear Twip Quadfecta,

I enjoyed listening to Dr Sara Dong’s febrile podcast. Thanks for making us aware of her podcast.

Listening to twip case 202, the Mumbaikar in me is shouting ‘TB TB’.

A man in his sixties living in a Rohingya camp in Bangladesh where living conditions are not that great suffering from chronic cough, night sweats, weight loss, with o2 sats in eighties, all these points towards Tuberculosis. He and his family members are also suffering from rash with Itching and this could be due to a Scabies infection.

My other differentials will be Strongyloidiasis and Amoebiasis.

In this patient, there is a chance of Strongyloides hyperinfection due to untreated diabetes leading to uncontrolled blood sugar levels. Stool O&P, sputum wet mount will be helpful in this case and serology can be done to rule out Strongyloidiasis.

Another differential will be Amoebiasis. A cough might be caused by diaphragmatic irritation due to hepatic abscess or there is a chance of hematogenous spread of amoebiasis leading to Pleuropulmonary Amoebiasis. Serology can be done to rule out Amoebiasis.

But I guess that this gentleman is suffering from Tb due to Mycobacterium tuberculosis.

Sputum ZN smear, Genxpert, MGIT culture and culture on LJ can be done.

Genxpert and MGIT culture has revolutionized the whole TB diagnosis and treatment.

Now that you can perform TB drug sensitivity within 2-3 weeks is a boon thanks to MGIT.

For scabies, Permethrin ointment can be given to the patient as well as to family members.

And socially small steps should be taken to improve refugees’ economy and living conditions. One thing is sure that eventually, refugees anywhere in the world will come out strong as they have faced the worst.

Thanks for the edutainment.


Dr Dhruti Sheth

M.B.B.S., 2nd year DNB Microbiology,

Breach Candy Hospital


Jillian writes:

Hello fellow TWIP-ers and esteemed hosts,

I’m writing you from a snowy Ottawa, Canada, where it is currently -30C (-22F) and the forecast calls for flocks of yahoos in trucks clogging up the downtown core, so I’ve decided to pass my time catching up on TWiP to drown out the honks (worse than the geese – they are!).

In terms of my answer, I believe that this gentleman is suffering from an intense and prolonged infection of sarcoptic mites, complicated by untreated diabetes; additionally complicated by a likely Staph. infection leading to rheumatic heart disease, possibly brought on by the diabetes-mites one-two punch.

First the parasites, infection with human scabies (Sarcoptes scabiei var hominis), is characterized by an intensely itchy red rash, typically in areas with skin folds, such as the elbows, knees, and abdomen. The areas between fingers are not typically described, but I would hazard this is likely due to handwashing behaviours which could inhibit the mite’s colonization of this space and/or serve to reduce the buildup of the parasite’s detritus, as it’s the body’s reaction to the parasite’s proteins and feces which causes symptoms of infection (CDC). Rather like the claxon-ringing flag-flappers outside my window, it’s not their presence that’s the issue – but that they are poorly behaved. Additionally, the itchiness associated with mites is often worse at night, which Dr. Griffin mentioned. Further, it’s telling that his family began showing symptoms of the parasite several weeks after him – reactivity to the detritus of the mites can take up to two months from time of infection, so this delayed pattern is what we’d expect to see in his cohabitants.

Sarcoptes scabiei has a global distribution and, unfortunately, is commonly associated with vulnerable populations in areas with cramped living conditions and poor sanitation and was listed one of the Neglected Tropical Diseases by WHO in 2017 (WHO).

In terms of diagnosis and treatment, if the equipment is available, then a dermatoscope could be used to view irritated areas or skin scrapings can be examined to look for the mites and their detritus. Considering that the family as a whole appears infected, looking at bed linens and other upholstery could be useful as well if that option is better received. In terms of treatment… I’ve found a very interesting preprint outlining some of the challenges of typical treatment strategies in Refugee/Migrant camps (Richardson et. Al) and it would seem that oral ivermectin (if the people driving past left any on the shelves) would be ideal.

In terms of other complications and where it all comes together – this individual noted that his first issue was actually frequent urination, thirst and weight loss, these are typical signs of Diabetes mellitus, which seems born out by his elevated blood glucose on examination (CDC). Unfortunately, both prolonged mange infection and untreated diabetes are risk factors for bacterial infections (such as those from Staph or Strep), which can themselves progress to pneumonia and/or rheumatic heart disease (WHO). As this individual is reporting problems breathing, but no cough – I would hazard that they are in the early stages of RHD. Along with treatment of the individual in question, it would be ideal to culture the bacteria to ensure that this isn’t an outbreak of a more serious nature – mange aside – if there are several individuals in his family showing signs of respiratory illness.

Thank you so much for all your wonderful work and this fantastic show! Although I once had rose-coloured dreams of arctic parasitology, hence my “humans – I don’t know her” response to treatment, I am now a digital educational specialist and really appreciate the chance to participate. (Also can I just take a moment to say that Christina – you are my absolute hero, it’s been so wonderful to hear from a female in the field!)


Christine writes:

Dear TWIP team!

I am a long term listener of TWIP and “pandemic listener” of TWIV. This is the first time I dare to send in a guess. I am working as a neurologist in Oslo, Norway. (nice and sunny, +5 degrees celsius, still windy after a storm last night. Too warm, and too little snow for the season).

This case seems to be a question of Ockham’s razor (entities must not be multiplied unnecessarily- find one diagnose that explains all of the patients symptoms); or Hikham’s dictum ( the patient can have as many diagnoses as he damn well pleases). Apparently, doctors prefer the razor… [Oxford handbook of clinical medicine 10th. edition, page 4. //.]

Maybe there is a parasite that elegantly explains everything, but in that case, I don’t know it. Dr. Griffin also pointed strongly towards a combination of causes.

 I think the patient has three conditions:

1. thirst, increased production of urine and weight loss is consistent with diabetes mellitus. Blood glucose 300 confirms the diagnosis.

2. The parasite involved here is Sarcoptes scabiei, causing scabies. The description of the rash, the itching, the whole family affected and living in a refugee camp all fits well with that.

3. He probably has Covid. One week of general viral symptoms, worsening in the second week with an oxygen saturation around 80 sounds like it. Living in crowded conditions will increase his risk, and with an untreated Diabetes and older age he is at higher risk for developing severe disease than his family.

Thank you so much for your excellent work!


Eric writes:

Hello TWIPpers, greetings from Seattle. I haven’t sent a guess for a while, but I look forward to every episode and every case. This month Daniel presented an intriguing case and I’m grateful that we got the hint that there may be multiple things going here because tying them all into one parasitic infection would be tough! I’m going to go for a triple: for the rash that he and his family members are afflicted with, I’ll go with scabies. For the acute fever and trouble breathing, COVID-19 is the most likely diagnosis. For the high thirst and glucose and urination, type 2 diabetes seems the most likely. Not a parasite, but serious nonetheless. I’ll even go for one more as an add blastocystosis as well because of the circumstances.

I so much appreciate all your TWIX episodes. I’m now listening to the TWIV with Jon Yewdell and I’m just blown away, what a great episode!

All the best,


Lisset writes:

Hello dear TWiP professors,

I am delighted to be back sharing my thoughts with you on this fascinating case from the beautiful island of St. Maarten at 80F. I hope the incubator is keeping you as warm as I am in the Caribbean.

In regards to last episode’s case, I believe this man is presenting with diabetes – due to frequent urination and increased glucose -, and I will venture into the wild and say that he could have COPD due to the heavy smoking and decreased saturation. I don’t bet my money on the previous diagnoses but I am fairly sure that the parasite that the patient is presenting with is Sarcoptes scabiei. This arthropod burrows into the skin creating tunnels through the top upper layers where it lays eggs. Fascinating! How am I so certain you wonder? Well, he’s living in a very crowded area and the intense itching is localized to webbing in between the fingers and elbows. Unfortunately, this is transmitted through direct contact so that’s why we see a similar presentation in his close family members.

I will leave all the juicy parasitic details to you so I can keep this email short, but all this information comes from the best parasitology book ever written: Parasitic Diseases, 7th Edition.


Lisset (she/her/hers)

Eyal writes:

Dear sages of biological knowledge and common sense. Greetings from sunny Sydney Australia where the temperature right now on the Northern Beaches is 30C with hardly any wind and 62% humidity. Frankly, a bit too warm but really I shouldn’t be complaining 🙂

First I would like to say that I’m not medically trained in any way or even properly educated in Biology or Chemistry (mainly did mathematics and physics in uni). However, after stumbling across Prof. Racaniello’s virology course and then Prof. Barker’s, followed by all things TWiX I’ve been inspired to expand my knowledge in biology and biochemistry. I also found Prof. Despommier’s and Dr. Griffin’s Parasitism course mind-blowing and at points downright disturbing.

Thank you all so much for the knowledge and perspective you share.

I’ve never submitted a guess before, as I normally listen to the TWiP episodes too late. But this time I thought I’ll venture a guess.

My guess for the case of a 60-year-old male in the Rohinga camp who has been waking up at night for 3 months is Scabies.

Listening to the description of the cramped and dirty (dusty) living conditions and the type and location of the itchy rash reminded me of my time in the Israeli army. In cases where beddings were not properly ventilated and de-dusted, there used to be scabies outbreaks that were extremely transmissive and the rash would keep people up at night scratching themselves bloody.

In my mind, the rest of the symptoms seem like a much bigger issue but probably a red herring in the parasitism context.

my guess would be that the thirst and loss of weight is a result of untreated diabetes which I think matches the high blood sugar. As for the fact that he has been feeling crummy (and Daniel mentioned that he is not the only one in the camp who has been feeling poorly) and the difficulty in breathing, I would guess that the culprit is Omicron (a guess from a different podcast :)).

Being completely out of my depth here I would guess that treatment should be dexamethasone and oral Ivermectin (lol) for the Scabies with a treatment plan to manage his diabetes once he hopefully recovers.

Please keep up your amazing work.


Martha writes:

Dear TWiP team,

I hope this finds you all well.

I’m responding to the case of the 60 year old man in a Myanmar adjacent refugee camp who developed diabetes, then a rash and then respiratory symptoms. This has me a bit stuck trying to come up with a single parasite to explain the whole story.

 First, the etiology of his diabetes. He is not of the usual age to develop type 1 diabetes. He does not fit the stereotype of someone developing type 2 diabetes. It could be one of the types of secondary diabetes, such as iron overload or cassava toxicity. Malnutrition related diabetes is described as developing in a younger person. There is LADA, latent autoimmune diabetes of the adult.  Diabetes could arise from pancreatic damage by cysticercosis or hydatidosis, but those are animal tapeworms that have hit a dead end in a human host.

Let us suppose that it is either Echinococcus granulosus or Taenia solium that have formed cysts in the pancreas and the host now has diabetes. From the effect of diabetes on the immune system the person is now prone to infection by another parasite or by reactivating a latent parasite. Since his younger, non-diabetic and non-smoking family members also have the rash symptoms, let us say that it is a new infection. Given his history, it is likely he will develop more severe symptoms. (I am of course ignoring the fact that he could have CoVID 19)

We are looking for a human parasite that can cause a rash and during its migration in the host has a phase passing through the lung.  Ascaris lumbricoides, Ancylostoma duodenale and Strongyloides stercoralis all have the ability to cause pneumonitis.

A. lumbricoides antigens trigger allergic response in the lungs and could possibly cause a atopic dermatitis. A. duodenale produces pruritic dermatitis at the site of entry. S. stercoralis can produce larva currens rash and also petechial purpura on the abdomen.

The history of rash on the abdomen makes me weigh in favor of the Strongyloides as the cause of his disease.

Also, thanks for the book. It arrived at a good time to help me sort out this case.

All the best to you,


Chelsea writes:

I have been listening to all of the this week in _____. Podcasts since just before the pandemic.  I love them all (including urban agriculture).  I am just an infection control practitioner from Alberta, Canada but thought I would try to solve the parasite puzzle of the month!  Hearing Daniel say there might be a few things going on with this client I am thinking the following:

Getting up at night to urinate, thirsty and losing weight sounds like common indicators of diabetes to me.

Rash on elbows, abdomen and between the webs of the fingers sounds very textbook scabies

Headache, fever, cough, trouble breathing sounds very much like a case of COVID

According to a variety of sources, frequent urination (often at night), being very thirsty and losing weight without trying are the first three symptoms of diabetes.

Correct or incorrect I look forward to writing in again!


Chelsea Hagg CIPHI(C), CIC

Infection Control Practitioner

Infection, Prevention and Control

Chinook Regional Hospital

Andrew writes:

Kia ora from Pongaroa,

It is hot here, 31°C so I am melting slowly into my keyboard. So I am grateful that this month’s case is not too hard. At least that is how it seems.

The Gentleman who is a refugee in Cox’s Bazar has what the Germans call Glück im Unglück – luck in the midst of misfortune. Why, because he probably has type two diabetes indicated by his unusual thirst and frequent need to urinate and elevated glucose. He also has, I think, scabies, the parasitic component that is needed to make it a TWiP case. Most worryingly he seems to have Covid-19 with the flu-like symptoms and an oxygen saturation down in the 80s. The luck is in that he has been forced to seek medical attention. Had he not untreated diabetes would most likely have led to an early death. Should he survive his CoviD he will be able to get treatment and make lifestyle changes that should keep his diabetes in check and live a longer life working in his shop and being there for his family. Had he not been forced to seek treatment his life expectancy would have been curtailed

The whole family will need to be treated for scabies with a scabicide and thorough washing of clothing and bedding -something that might be difficult in a refugee camp but necessary. The family should also be tested for Covid. Vaccinations in these camps only started late last year, according to Al Jazeera, so there will be a lot of people there who are vulnerable to infection and serious disease.

I read that while Covid has had my attention it seems an immigrant species of mosquito, Anopheles stephensi, has taken up residence in the Horn of Africa Mosquitoes as Vectors of Plasmodium vivax and P. falciparum turning what was mainly a rural problem into an urban one. Am I right in thinking that this is a very scary development?