Recording intelligenceAI-generated brief · check the source for context

Parasites in Travelers

47:41 recording · AUTO · 3 speakers

Listen to the original

Listen to the episode

Brief overview

A traveller's three stool parasites came down to Giardia, cured by four 500 mg tinidazole tablets.

  1. Four tablets was the diagnostic clueFour 500 mg tinidazole tablets taken at once point straight at giardiasis, and most guessers ignored the dose.
  2. Treat the parasite driving the symptomsH. nana is usually an innocent bystander and Blastocystis often needs no treatment in the immunocompetent.
  3. Fish parasites threaten aquaculture and food securityIntensive farming, high stocking densities and waste give parasites ideal transmission conditions as fish supply grows about 3% per year.
Executive Summary AI
  • TWIP episode 274, recorded 6 February 2026, has Vincent Racaniello hosting Daniel Griffin from New York and Christina Naula from Glasgow, just back from Malaysia.0:00
  • Daniel recaps the case: a 40-year-old HIV-negative man spent a week in New Delhi, developed bloating, diarrhoea and flatulence, and his stool came back positive for Hymenolepis nana, Blastocystis hominis and Giardia intestinalis, after which he took four tablets and felt better.1:58
  • Listeners guessed praziquantel, metronidazole, nitazoxanide, albendazole and tinidazole, and Philip sent a price table showing absurd costs such as $9,000 mebendazole in the US and albendazole at 218 euros where it is about 50 cents a tablet elsewhere.4:06
  • The answer was four 500 milligram tinidazole tablets: Giardia was almost certainly driving the symptoms, Blastocystis was incidentally helped, H. nana was ignored, and the patient did well; Henrik in Tübingen won the eighth-edition book.25:18
  • Christina's hero is fish parasitologist Glenn Hoffman, born in Iowa in 1918, who wrote the Parasites of North American Freshwater Fishes, and Daniel closes with a new case: a man in his 60s born in El Salvador who lost 50 pounds in three weeks and has a gastric mass plus multiseptated liver lesions.41:20
Key Quote
“Did he drink from the Ganges?”
— Christina Naula8:26
Key Quote
“And this is for giardia. So what are you going with, Vince?”
— Daniel Griffin23:56
Key Quote
“that was that was actually the thought process that of these, you know, three findings in the stool, that probably the Giardia was driving the symptoms.”
— Daniel Griffin24:22