Correction: May 9, 2013: 3:18 p.m. USDA spokeswoman Tanya Espinosa said that the snail found by a gardener in Houston was not, in fact, a giant African land snail, but a rosy wolf snail, which is a fairly common snail in Texas. “We have no reason to believe that the Giant African snail is in Texas,” Espinosa said. She advised if you find a snail and want it identified, do not touch the snail, but scoop it into a plastic container, put a lid on it and contact your local state department of agriculture.
Everything is bigger in Texas, even the invasive species and the health fears surrounding them.
Recently, a gardener discovered a giant African land snail (Achatina fulica or achatina) in her yard in Houston. News outlets raised an alarm about health risks from the supersized snails.
The menacing mollusks can host the parasitic rat lungworm, Angiostrongylus cantonensis, which can infect humans if the snails are eaten raw or undercooked, according to the Centers for Disease Control. The parasitic infection sometimes leads to a rare type of meningitis, known as eosinophilic meningitis.
“The parasite dies over time, even without treatment,” according to the CDC’s website. “Even people who develop eosinophilic meningitis usually don’t need antibiotics. Sometimes the symptoms of the infection last for several weeks or months, while the body’s immune system responds to the dying parasites.”
Angiostrongylus cantonensis infections are rare in the U.S., noted the CDC. One reported case in 1993 resulted from a boy swallowing a slug on a dare. The boy won the bet, but also caught the parasite. He was ill for about two weeks, but his body fought off the infection without treatment.
Other species of mollusks, including native slugs and snails, and some frogs and crustaceans can host the parasite as well. Mollusks pick up the parasite if they eat infected rat feces.
Doctors don’t know if the giant African land snails invading the U.S. carry the parasite. The Michigan Department of Agriculture warns that even if the snails don’t carry A. cantonensis they should still be handled with care. The snails, like many other animals, can harbor salmonella or other bacteria.
While the health risks from the snails may be relatively small compared other dangers Americans face everyday, such as automobile accidents, the ecological and economic risks equal the gigantic proportions of the snail.
The supersized snails threaten Texas vegetation and crops, since the voracious pests will eat just about any plant and will even chow down on stucco and other building materials.
The snails are prolific breeders and don’t need to mate with others of their kind since they carry both male and female genitalia. The hungry hermaphrodites can lay more than 1,000 eggs per year. Their indiscriminate diet and fecundity has made the snails a serious and well-established pest in the Caribbean, Florida, and parts of Asia.
IMAGE: Giant African land snail, Achatina fulica (Drajay1976, Wikimedia Commons)