Giant African land snails may seem like slow-moving, harmless animals.
But, in fact, they are “one of the most harmful snails in the world and a potential risk to human health”, according to the US authorities who are hunting this invasive species.
“They are dangerous to our health because they carry parasites called lungworms, which can cause meningitis in humans,” Florida Agriculture Commissioner Nikki Fried said at a news conference earlier this month in Pasco County, on the west of the state.
“They consume at least 500 different plants, which makes them a clear threat to our agricultural and natural spaces.”
Specially trained sniffer dogs and a team of at least 30 people are searching through lush Florida gardens to eradicate this invasive species.
Since their latest discovery in June, officials have captured more than 1,400 live and dead snails in Pasco County, according to local media.
Giant African snails can grow up to eight inches and reproduce quickly. “A single giant African snail can lay up to 2,000 eggs each year,” he told the agency. AFP Jason Stanley, a biologist with the Florida Department of Agriculture.
threat to humans
But are humans also in danger? Potentially yes, according to experts.
These snails often harbor rat lungworms which, if ingested by humans, can travel to the brainstem where they can cause meningitis.
“Normally, it does not affect people. But if they accidentally get into a human, the immature worms can get lost and can end up in places where they might do a lot of damage, like inside the eyeballs or even the brain,” says Dr. William Kern, Associate Professor in the Department of Entomology and Nematology at the University of Florida.
A quarantine zone has been established within New Port Richey: no plants or other vegetation can be removed from the area to try to prevent the snails from spreading further.
To prevent infection, even dogs are trained not to catch snails in their mouths.
Has this happened before?
Yes. The first invasion happened in the 1960s. It took seven years and a million dollars to finish it off. The second occurred in 2010 and this time it took ten years to eradicate them at a cost of US$23 million.
Only if there is no sighting of snails for two years, the authorities might declare the place free of snails.
In Europe, some people keep these snails as pets, but in the US it is illegal to keep them without a license. However, officials and experts suspect that this invasion may be due to pet dealers.
“It is very likely that someone brought them in as pets. The ones we found in Pasco County have white skin instead of the normal gray color,” Dr. Kern told the BBC.
Originating in eastern Kenya and eastern Tanzania, they are now found in many places around the world, including South and Southeast Asia.
The US Department of Agriculture says, “This mollusk is now established on many of the Caribbean islands, much of South America, and more recently was introduced to Costa Rica.”
not fit to eat
Florida officials are now asking people to report any sightings of these snails.
“If you see one of these snails, don’t touch it. Call us. They carry diseases like meningitis with them,” says Commissioner Nikki Fried. She also has a warning for those who would rather see them on a plate than in her garden.
“The most important thing is that you don’t eat them. This is not a snail to put in butter, oil and garlic.”