[Investigation on outbreak of angiostrongyliasis cantonensis due to consumption of snail food in Dali City].

OBJECTIVE: To investigate the potential cause of an outbreak of eosinophilic meningitis in Dali City in March, 2011. METHODS: A retrospective investigation was performed among 18 consumers who had meal together. The clinical documents of inpatients were analyzed and the diagnoses were checked. The outpatients were investigated through a case survey. Pomacea snails on sale were examined for the infection status of Angiostrongylus cantonensis. RESULTS: Of 18 persons, 16 consumed Pomacea snail food and 9 were infected with an infection rate of 56.3%. The two persons who did not consumed snail food were not infected. Serum samples of seven patients were examined for antibody to Angiostrongylus cantonensis in peripheral blood and 3 were proved positive (42.9%). The snails consumed by the patients came from the market, and the surveillance data showed that the infection rate of Angiostrongylus cantonensis of Pomacea snails was 7.3%. CONCLUSION: According to the epidemiological survey, clinical manifestations, and laboratory examinations, the outbreak of eosinophilic meningitis is due to the consumption of Pomacea snails infected with Angiostrongylus cantonensis.