The Florida Department of Agriculture and Consumer Services warned residents of Pasco County, in particular, to look out for the snail.
"The giant African land snail … is one of the most invasive pests on the planet, causing agricultural and environmental damage wherever it is found," the alert said.
The snail is popular in the pet trade in other countries, the alert said. But it is prohibited by federal law in the U.S. and can’t be legally owned or sold.
The snail, scientifically known as Lissachatina fulica, can carry a rare rat lungworm called Angiostrongylus cantonensis, which can cause meningitis in humans and animals. Most cases of rat lungworm disease occur in parts of Asia and the Pacific Islands, but some cases have been identified in the U.S., including in Hawaii and Louisiana, according to the CDC.
People can get the disease when they eat raw or undercooked snails or slugs that are infected, as well as fruits or vegetables that haven’t been washed well. Some people have gotten infected by swallowing snails or slugs "on a dare," the CDC wrote, while others have gotten infected after eating raw produce, such as lettuce, that contains a small snail or slug.
Some infected people don’t have any symptoms or only report mild symptoms that don’t last long, the CDC said. But the infection can cause a rare type of meningitis, called eosinophilic meningitis, that includes symptoms such as a headache, stiff neck, tingling or painful feelings in the skin, a low-grade fever, nausea, and vomiting.
"Most infections … resolve spontaneously over time without specific treatment because the parasite cannot survive for long in the human body," the CDC wrote. "However, serious complications can rarely occur, leading to neurologic dysfunction or death."
The snail has become established in southeastern Florida twice and was successfully wiped out both times, according to a recent report from University of Florida researchers. The state first did away with the snail in 1975 after finding it in 1969 and recently got rid of it in 2021 after finding it in 2011 in Miami-Dade County.
But on June 21, a Pasco County master gardener reported a possible sighting of the snail in New Port Richey, in the Tampa-St. Petersburg-Clearwater metropolitan area. On June 23, investigators surveyed the property and confirmed the presence of a white form of the snail. The Division of Plant Industry for the Florida Department of Agriculture and Consumer Services then ordered a quarantine and began treatment on June 29.
"The phenotype in Pasco County has a creamy white flesh as opposed to the grey-ish brown flesh of the phenotype that was eradicated in the Miami area," Erin Moffet, the department’s communications director, told Fox News.
Mellon, a mollusk detector dog, is now actively looking for the pest, Moffet said.
The department is treating properties with a snail bait that is a metaldehyde-based molluscicide labeled for residential use by the EPA, according to the department’s website. The pesticide is approved for use on many crops, fruit trees, avocado and citrus orchards, berry plants, and banana plants.
"The giant African land snail is one of the most damaging snails in the world and consumes at least 500 different types of plants," the department said. "These snails could be devastating to Florida agriculture and natural areas as they cause extensive damage to tropical and subtropical environments."
The snail can survive in many environments, the department said. They are mostly active at night and hide in cool, damp places during the day. They can move long distances when clinging to vehicles, machinery, or yard trash. During bad environmental conditions, they can burrow into soil and remain inactive for up to a year.
Florida officials encourage Florida residents to contact the Division of Plant Industry with any suspected reports of giant African land snails. People can contact the division via its helpline at 888-397-1517 or DPIhelpline@fdacs.gov to submit pictures and details.
Florida Department of Agriculture and Consumer Services: "Pest alert, FDACS-P-01717, June 2022," "Giant African Land Snail pest information."
CDC: "Parasites – Angiostrongyliasis (also known as Angiostrongylus infection): Angiostrongylus cantonensis FAQs."
University of Florida: "Terrestrial snails (phylum Mollusca, class gastropoda) affecting plants in Florida."
Fox News: "Florida warns residents of giant African land snail that may cause meningitis in humans: report."
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Cite this: Florida Warns About Snail That May Cause Meningitis - Medscape - Jul 06, 2022.