Foodborne Illness

Rat lungworm explained: What to know about the parasite found in Florida

A "rat lungworm" parasite has been found in multiple Florida counties, according to University of Florida researchers.

Why should you worry? Escargot lovers may become infected with the parasite if they eat raw or undercooked snails. 

Here's what you should know about the parasitic roundworm, Angiostrongylus cantonensis, and how it can be avoided. 

Where is the parasite found? 

Its adult form is found just in rodents, and sickened rats can pass larvae of the parasite in feces, the Centers for Disease Control and Prevention says online. 

How are snails, slugs and humans infected? 

Snails and slugs become infected when they ingest the larvae. Humans consuming raw or undercooked infected snails and slugs may end up with rat lungworm, the agency warns. Eating raw or undercooked freshwater shrimp, crabs or frogs infected with larvae may also be an issue.


Another way people can be infected is if raw produce contains a snail or slug, the CDC says. It's important to note that if someone's infected, they cannot transmit the parasite to somebody else.  

Where have there been cases in the U.S.? 

Humans were infected in Hawaii, Louisiana and Texas, University of Florida researchers say. Most recently, researchers found rats and snails that tested positive for the parasite in five Florida counties: Alachua, Hillsborough, Leon, St. Johns and Orange. Earlier studies found the parasite in the southern part of the Sunshine State. 

What sort of preventative measures can I take? 

Skip eating raw or undercooked snails and slugs, and make sure to wash your hands and sport gloves if you're handling them, according to the CDC. 


What's known about symptoms? 

Those who suffer symptoms can experience "headache, stiff neck, tingling or painful feelings in the skin, low-grade fever, nausea, and vomiting," the CDC says, explaining that eosinophilic meningitis may be caused by the infection. Not everyone who is infected exhibits symptoms.

What should I know about treatment? 

While treatment is not usually required and the parasite eventually dies, University of South Florida researchers warn that coma and death are possible with severe infections. Patients can be treated with medication for headaches and to lessen how the body responds to the parasite, the CDC says.