Infectious Disease Compendium

Baylisascaris procyonis


A roundworm parasite.

Epidemiologic Risks

Raccoon poop. Raccoons like to crap in the same place time after time (they call them raccoon latrines) and their stool is filled with this parasite.

People accidently (or so one hopes) handles the egg containing poop and then puts their hands in their mouth. Or eats an animal with the eggs. Children at risk as they tend to play in the dirt, oblivious to any risk (PubMed). I always remember the time my son ate a slug before I could to him: from the dirt to the stomach in the blink of an eye.

B. procyonis roundworms are most prevalent in the midwestern, northeastern, and Pacific western states and in the mountainous regions of Virginia, Kentucky, and West Virginia.

Has also been found in pet Kinkajous (CDC) and there are a variett of Baylisascaris, each with their own hosts.

About 7% of wildlife rehabilitators (who knew wildlife had drug and alcohol problems; probably why they are called wildlife) are seropositive suggesting subclinical infection (Pubmed)(PubMed).


Meningitis/encephalitis, often eosinophilic. Rare but fatal.

No serology but as the CDC notes "eye examinations may reveal a migrating larva or lesions and are often the most significant clue to infection..." Eeewwww.


Albendazole and dexamethazone for months.


The eggs are very resistant to death: "Loss of viability resulted when eggs were heated to 62 C or desiccated for 7 months but not when frozen at 15 C for 6 months (PubMed)." So don't eat your racoon rare.

Last update: 05/05/18