Wink Weinberg writes:
Do leishmania eat bacteria?
As always, I enjoyed the last episode of TWIP about cutaneous leishmaniasis and raised several comments I would like to share with the TWIP audience.
- In the article discussed, the authors investigate the role that transmissible skin microbiota could have on the infection outcome. With this purpose, the authors study the microbiota from the same side and compares with that of contralateral microbiota. I would like to comment that, at least in humans, this must be taken with caution, since the microbiota of the right hand is different from that of the left one. This is logic, because physical contact is much more pronounced with the dominant hand. It should be mandatory to know the basal differences (without lessons) between both sides.
- In the show, Dr. Despommier guess whether some fungal infections could produce some antibiotics in situ to prevent bacterial co-infection. In fact, this was demonstrated a long, long time ago. First of all, we have penicillin, that was discovered when a Staphylococcus aureus strain in a Petri dish was inhibited by a contaminating Penicillium strain. This was of course in vitro. But, very interestingly, it was shown in 1980 that, in patients infected with Tricophyton mentagrophytes fungus (one of the most common causes of ringworm in humans), a Penicillin-like antibiotic could be detected inside the fungal lesions but not outside them.
- On the other hand, fly larvae have been shown to have antibacterial properties despite the fact that the exact mechanisms are poorly understood. I put a link below. Again, and as in the case of Leishmania, is of fungal and parasitic interests to avoid bacterial coinfection that could directly or indirectly compromise the success of the infection.
An interesting review article “Selective antimicrobial activity of maggots against pathogenic bacteria”
Thank you very much again and I hope hear from you soon!!!
Dear friends and my own Nominees for the Nobel prize!:
Here is another interesting case presented from Dr Griffin. It is all about the finding of small “creatures” that seem to be attached to hair shaft.
I think of only two possible infectious diseases that could match this description. One is a fungal disease caused by two species: Piedraia hortae and Trichosporon beigeli. Many years ago, Dr. Horta classified the diseases called “Piedra” (Piedra means stone in Spanish) in two types Black Piedra and White Piedra, whose ethiological agentes are Piedraia hortae and Trichosporon beigeli, respectively. Black piedra si common in hot and humid countries such as Dominican Republic. Black piedra usually affects the scalp while White piedra could affect any body part. The name “Piedra” (=stone) refers to the hardy consistency of the typical nodules that are found in hair shafts and that actually are hyphal masses of the fungus.
But,of course, we are in TWIP, so I will discard the fungal infection and I will go for the parasitic one. The description suggests we have a case of human louse infection. In examination we could look for the adult and the eggs, called nits, both of them living in close association with the hair shaft. These creatures are blood feeding animals!.There are two closely related subspecies, Pediculus humanus var. capitis and Pedicures humanus var. corporis. There are several species of louse each one specific for his animal species. The specificity comes from the different hair diameter, so each lice is provided with terminal grasping hooks and can only attach to the hair with a specific diameter that perfectly match the diameter of those hooks. So human can only be infested with the human louse. Body louse but no head louse, can transmit several diseases, such as epidemic typhus, trench fever and louse-borne relapsing fever. There are several successful treatments but as it seems the family cannot afford them, the most successful and cheapest treatment could be a hair cut, leaving no hair for the parasites to attach to!. Since it is a very transmissible disease it should be mandatory the examination of all family members to detect unsuspecting cases or even to adopt a mass treatment (haircut for all family members!).
P.S. History is always interesting. And sometimes molecular studies give us with perplexing information. These molecular studies have shown that human pubic louse and gorilla pubic louse are very closely related and diverged very recently. They did so after human beings and gorilla diverged long time ago. What this means is that humans and gorilla shared much more what they were supposed to share and different hypothesis have tried to explain this. Remember that this type of louse are sexually transmitted. The authors speculated that human and gorilla could have had much closer contact than expected but the most likely explanation is that they could have shared the parasites sharing the same habitats, for example sharing the nests.
Thank you very much again and I anxiously wait for the next episode.
Dear TWiP triumvirate, thank you for another fun case of the week!
The young boy with poppy seed sized things on his hair shafts is most likely exhibiting irritability due to itching and discomfort due to Pediculus humanus capitis, commonly known as the head louse. Although I don’t recall ever hearing about them when I grew up in the northeast US, here in the northwest US, it seems very common for most children to acquire them at least once in the schools. Medications are not necessary. The best treatment is just combing the hair with a special lice comb, easily available here for 10 USD. A few combings a few days apart and they will be gone. If such a lice comb is not available to this mom and boy, then the cheapest solution may be just to shave off the hair for a while. Head lice cannot infest where there is no hair.
Seattle is enjoying sunny and 28 C, but super dry with a July-August rain total of 0.02 inches.
Just came across this story of Sarcocystis causing 400 Irish sheep carcasses to be destroyed–with the report taking a bit of an uncalled for swipe at ‘livestock-worrying dogs’, that might have had nothing to do with it but a ‘knee-jerk reaction’ from farmers’ sorry for their loss.
Anyhow, the article has a link to a good Stanford site for parasite info that I don’t recall being mentioned on TWiP before. Both sources say the parasite is rarely of concern in humans, but the Stanford one says that, when it does occur in humans, the disease is usually attributed to Isospora belli. It goes on to give some actually rather high occurrences of the cysts in the tongues of habitual raw meat eaters in East Asia, and some places where most of the meat in markets was infected, and in Lebanon where the ‘national dish’ is a raw meat one called ‘kibbe’ (Has Daniel tried kibbe? 😉 ).
Dickson et al’s Parasitic Diseases 6th ed pdf, hardly mentions Sarcocystis, and, when one looks for Isospora belli, we get Cytoisospora belli as the new name, and only a mention of concern in immunocompromised people, where, as with Toxoplasma gondii, the results can be devastating. The Stanford pages don’t mention the name change, but give Sarcocystis as only having two species of concern to humans: that of cattle, and that of pigs, but this is contradicted by the mention of the East Asian, South American, and Lebanon notes in other sections.
I would imagine that Parasitic Diseases is the most up to date with the names, but, judging by the widespread occurrence of the parasites given in the Stanford source–even in people’s tongues and necks, in some regions of the World–, the difficulty of distinguishing them from T. gondii, in immunological tests, and the economic losses from infected animals where food hygiene regulations are more stringent, might they deserve a bit more of a mention in further revisions of the book; and, perhaps a clearing up of which names belong to which parasites, and which diseases, in a future TWiP podcast? I’m not at all clear from comparing these accounts, just which parasites are the ones getting into which animals and which people in which places. 🙂
All the best,
This beautiful parasitic bird could end up in your yard.
“These birds don’t look like a virus or bacteria, but they have the same impact,” Dr. Hauber said.
Brood parasites compete with their hosts. And the host birds must work harder to support themselves, their own young and the offspring they are tricked into fostering. Over time, it takes a toll on the hosts
Qatar blockade is a warning to all desert countries that rely on imported food
http://theconversation.com/qatar-blockade-is-a-warning-to-all-desert-countries-that-rely-on-imported-food-80283?utm_medium=email&utm_campaign=Latest from The Conversation for July 5 2017 – 77756158&utm_content=Latest from The Conversation for July 5 2017 – 77756158+CID_2249192bf4f04096332b2e0105788fc4&utm_source=campaign_monitor_uk&utm_term=Qatar blockade is a warning to all desert countries that rely on imported food
One for Dickson:
Has he investigated Qatar for vertical farm potential? It would appear to be an ideal proving ground, where money is almost unlimited, but water is very scarce.
All the best.
Steve: in Luton, England; where the weather is warm and sunny.
Dear TWiP professors,
Greetings from South Sudan! I’m currently here working as an epidemiologist for Doctors Without Borders. Given last week’s case, I couldn’t help but write in with a diagnosis: Dracunculus medinensis, or ‘Guinea worm’. Given I’m in one of the four last countries reporting cases of Guinea worm (Chad, Ethiopia, Mali, and South Sudan according to the CDC), I am acutely aware of its presence…
I’ll let other listeners describe the interesting treatment since I’m sure many others will recognize this distinctive parasite. Instead, I’d like to offer you an idea for another TWiX series: This Week in Global Health (TWiGH – which you could pronounce like ‘twig’). I became a regular listener to TWiP when Daniel did the series of cases based on his consultations for the Peace Corps. I think it’d be interesting to have a series where you look at the ‘bigger picture’ and it’d be a good place to talk about new research that cuts across the current TWiV/TWiM/TWiP lines. For example, there’s been quite a bit of interesting research on co-infections of non-typhoid Salmonella bacteraemia and malaria
(https://malariajournal.biomedcentral.com/articles/10.1186/1475-2875-13-400). Perhaps in addition to talking about new research in global health/tropical diseases, you could pick a particular country/region each week and describe the major causes of morbidity and mortality. Just a suggestion since there’s occasional talk of starting a new series. Thanks for the always interesting and informative podcasts!
My son and I are infected with a Trematode, of which I can see with the naked eye (fasciola of some sort). We have had 3 negative stool samples done by military medicine in Twentynine Palms Ca. We were infected in Okinawa, Japan (theyb still use human feces as fertilizer on the island) in either the Okawa kin town fresh water spring splash pad or camp Hansen mud run. My son nursed post run April 25, 2015 received slight rash on face may 7 2015, and full blown schistosome looking rash full body may 27th 2015 with fever. We went to the ER with both rashes and sent home basically no diagnosis. Now I took baby to ER with crazy stool may 2017 and have experienced and seen two life cycles with images. I have tortured myself with juice cleansing wormwood enama to pass the adult.
We have passed eggs flukes male females and I have passed an adult. I have images of both cycles. We were prescribed alinia dr assumed it was an Asian tapeworm. We have appointments with GI doctors wishing it was infectious disease.
I have an image of what I think looks like fasciola gigantica or similar species waiting for the stool lab to come back positive… in which I don’t have much faith in this military lab.
My question is should I just go to an ER at a university to get taken seriously? Should I wait until the eggs come through again and immediately take those to the lab in hopes they finally identify them? Or do I put faith in the GI doctor that they will indeed find what they need to to treat us?
I would love to send you images and get your perspective. I love your podcast and it has been extremely helpful in trying to figure out what is wrong with us!
Thank you again,
I had to write in when I heard your conversation about name pronunciation in twip 133. It seems you guys missed the biggest difference in the name (as I would guess most Americans do)! His last name ending in -berg is pronounced “berg” by English speakers but in swedish as “berry” or very nearly so. I recommend relistening to his audio clip once more with a focus on the last name! Just for your edification, I am an American who has lived abroad in Finland for the past 4 and a half years. I recently got my citizenship here and have spent a lot of time learning both of the national languages here (Finnish and Swedish). Thanks so much for all you do, I love listening to TWI* podcasts while I work here in Helsinki. Today it’s a balmy 16C with sun and intermittent rain.
Your museum working friend in Finland,
Kelsi Vaahtojärvi (good luck pronouncing that, haha!)
I am staying with my daughter in Brisvegas where it is 18c – 65f precipitation 0% Humidity 35% and Wind 8 km/h. just caught up on TWIP 115 and was fascinated with the answer to the case study from 114. Not being in the medical profession everything sounded just like a really bad case of Thrush at least or at worst, Candida. Being an older female I have had experience of both in my lifetime with no on-going problems thank goodness. As the case was on TWIP and not one of the other programs I knew it must be something more than the usual but had no idea of the answer which was a revelation to me and no doubt others from a non-medical background.
I must add a point of clarification here, in the program I heard Dickson say that Australian’s say Strine for Australia… No we don’t… A “dyed in the wool” and that’s how you say it for a born and bred aussie, calls the best place in the world, Strayliaand the slang language of the country is called strine as in Aussie Strine or lingo I have provided a link below for Dicksons’ enjoyment and education on our colourful language.
For example, couldn’t kill em with a meat axe, might apply to some of your nastiest parasites or viruses.
I like many of the others that write to you truly appreciate these and the other twiv, twim etc podcasts as you make it so easy for me to learn something new every day.
While engaged in a round of chores the other day, I suddenly saw a mass of writhing worms before my eyes — to be specific, my right eye. “WOW,” I thought. “My very own TWiP case!”
Just a glance at a mirror revealed that the objects were not ON the eye, so had to be IN it. While trying to recall the discussions of parasites involving the eyes, I sat down to observe more closely and so formulate a description. I soon realized that the “worms” really were more like threads or spider web and that the movement was random floating. A Google search came up with
“… eye floaters are caused by age-related changes that occur as the jelly-like substance (vitreous) inside your eyes …”
Jeepers! Not only no interesting parasites, but ageism insult gets added to injury.