Today I was stumped by an egg. An egg in a stool sample from a young stray Appleton shelter cat. After 25+ years of examining parasite eggs under a microscope, I thought I could not be stumped. But this week, after some head scratching and internet researching and some denial, I sent this sample to Marshfield Lab Parasitology Dept for expert identification. The test results.....( Drum roll please.....)
This stray cat's fecal analysis revealed many tapeworm eggs called Diphylobothrium Latum. The mysterious question is why is this Wisconsin cat carrying a tapeworm found only in foreign parts like Thailand, Japan, Russia, Norway, Scotland?
Detective work unearthed the facts. This tapeworm, called the Fish Tapeworm, has an interesting life cycle. It starts as an egg in a mammal (cats, dogs, and yes, humans). The egg finds its way into the water supply and is ingested by a small water kritter, and up the food chain into large tasty fish (like salmon). If this salmon is ingested uncooked or undercooked, the parasite grows to adulthood in the fish-eating mammal (Fluffy, Fido, or you/me). A trip to the local grocery's fish section solves the International Mystery: shrimp from Thailand, cod from Norway, salmon from Scotland - we now have a global food supply at our fingertips. And also international parasites :)
The moral of the story is two fold. Even your indoor cat could be carrying parasites so have an annual stool sample checked as recommended.
AND always, always, always cook fish completely before consuming....(sushi-eaters beware!)
Dr. Maureen Flatley