A potentially deadly parasite has been found in various parts of Florida, a new study has found.

The parasite—rat lungworm—is mostly commonly found in rats and snails, but once it infects you, it can cause spinal cord and brain dysfunctions like meningitis. In its most severe cases, rat lungworm can put you in a coma or cause death. Other symptoms include:

  • blindness,
  • headaches,
  • sensitivity to light,
  • and vertigo.
Rat lungworm

Adult female of angiostrongylus cantonensis

Rat lungworm, known in the scientific world as Angiostrongylus cantonensis, is not native to the continental United States. Cases of the parasite have been found in south Florida in the past, but researchers recently found it in parts of north and central Florida, too. Rat lungworm thrives in tropical areas like Hawaii, where it’s most commonly found, and researchers credit the spread of the infection to climate change.

“The ability for this historically subtropical nematode to thrive in a more temperate climate is alarming,” a researcher said.

“We expected the range of this nematode to be restricted to one part of the state because it’s primarily a tropical species,” said John Slapcinsky, a collections manager who worked on the study. “But being within another organism could mean it’s less impacted by cold weather.”

As weather collectively gets warmer around the country, rat lungworm can survive in a greater area, which increases the risk of infections in more parts of the United States.

In the study of 18 counties across north and central Florida, researchers found the parasite in nearly 23 percent of rats, including 16 percent of rat feces that were sampled and 2 percent of snails. Samples of rat lungworm were found in five counties:

  • Alachua
  • Leon
  • St. Johns
  • Orange
  • Hillsborough

Other counties in the study range as far west as Okaloosa and as far south as Miami-Dade.

“The parasite is here in Florida and is something that needs to be taken seriously,” said Heather Stockdale Walden, an assistant professor at the University of Florida’s College of Veterinary Medicine who led the study. “The reality is that it is probably in more counties than we found it in, and it is also probably more prevalent in the southeastern U.S. than we think.”

“The ability for this historically subtropical nematode to thrive in a more temperate climate is alarming,” Stockdale Walden added.

How rat lungworm spreads

Rat lungworm life cycle

Rat lungworm is spread through a rather unsavory relationship between snails and rats. Snails (and slugs) eat rat droppings, which are home to the parasite. The snails are then infected, but the snails are eaten by other rats, and the never-ending circle rolls on.

Now, we know you may be wondering, “How does a snail get from Miami to Jacksonville? Let alone from Hawaii all the way to Florida?”

No, a snail navy didn’t just get a recent round of funding from a snail government. Snails often cling to objects to move. A snail can attach itself to produce or potted plants, and then they travel across land and sea with the vegetation until it gets to the new location.

Rat lungworm’s U.S. origins in Hawaii

Rat lungworm also made its way to a profile in The New Yorker. The profile began with the stories of two people—a 24-year-old construction worker and an orchid farmer—in Hawaii over a span of ten years.

The construction worker, Graham McCumber, fell ill to rat lungworm (doctors later found out) after eating kale from his garden in 2009. “Within a few days,” the story told, “his symptoms had given way to headaches, double vision, and widespread nerve pain. He fell into a coma. As the illness progressed, McCumber’s left eye turned inward in its socket and his organs started to fail.”

Cases of the infection in Hawaii increased from one in 2014, to 22 in 2016.

Mindi Clark, the orchid farmer who works with and eats copious amount of fresh produce and vegetation, had heard about McCumber’s experience years ago, but forgot about it by the time November 2016 came around. That’s when she started feeling ill following a camping trip. “She felt as though she were being burned alive in short, intense bursts,” the profile explained. Clark said, “I would just be screaming for help, and my husband couldn’t touch me because it was like I was electrified.”

The story says that McCumber is still recovering from his infection nearly eight years later. Clark said she’s mostly gotten through the pain of the infection.

Cases of the infection have increased in Hawaii from one in 2014, to nine in 2015, to 22 in 2016. Through the first five months of 2017, there were 16 reported cases on the state’s islands.

How to avoid rat lungworm infection

There are plenty of steps you can take to help prevent getting infected with rat lungworm, though. The first step is awareness, which you have already accomplished by reading this article.

Given the parasite’s ability to live in food, make sure to wash your produce thoroughly. It’s advised that you pay special attention to leafy greens like lettuce and kale before eating them. You should also watch out for eager children who may find and eat small snails. “Be aware of the potential risks associated with eating snails and also raw or undercooked frogs and crustaceans,” Stockdale Walden said.

Hawaii’s Department of Health also offered advice on how to prevent rat lungworm. “Eliminating snails, slugs, and rats founds near houses and gardens might also help reduce risk exposure” to the disease, the department’s site noted. They also suggest that you boil shrimp, land crabs, frogs, snails, and slugs before consuming them. It’s encouraged that you frequently wash your hands if you handle raw crustaceans, too.