Posted: Feb. 4, 2010
A cluster of recent cases of disease in Hawai’i caused by eating fresh produce contaminated with snails or slugs infected with the nematode parasite Angiostrongylus cantonensis, the rat lungworm, has drawn attention to this foodborne threat, which can cause eosinophilic meningitis. A publication on preventive measures to reduce spread of rat lungworm infection on farms is now available from the UH Mānoa College of Tropical Agriculture and Human Resources (CTAHR).
According to the publication by authors from CTAHR, the UH Pacific Biosciences Research Center, and USDA, slugs and snails become infected with rat lungworm in two ways. Most commonly, the slug or snail will eat contaminated rat feces. Less commonly, the nematode burrows into the slug or snail through the body wall or enters through a respiratory pore when the animal comes into close contact with the contaminated feces. Other vectors of infection include frogs, freshwater shrimp, and land crabs.
The publication, which was reviewed by the Hawai‘i Department of Health, informs commercial growers of the danger of rat lungworm and urges them to take precautions necessary to reduce their risk of transferring the pathogen to consumers. It emphasizes the importance of mitigating contamination on farms and in home gardens by removing rodent, slug, and snail hiding places; trapping and killing these pests; and discarding any produce with visible slugs or snails, or their slime.
Consumer tips to avoid risk of infection are (1) carefully rub, while rinsing, all produce before eating it; (2) sanitize food-contact surfaces to prevent cross-contamination; and (3) cook potential hosts, such as culinary snails or freshwater prawns, to an internal temperature of 165 degrees F before eating.
The document can be viewed at http://www.ctahr.hawaii.edu/oc/freepubs/pdf/FST-39.pdf.