[An epidemiologic investigation on infection with severe acute respiratory syndrome coronavirus in wild animals traders in Guangzhou].

OBJECTIVE: To investigate status of infection with severe acute respiratory syndrome coronovirus (SARS-CoV) in traders of wild animals wholesale markets in Guangzhou.

METHODS: Serum antibody against SARS-CoV IgG was determined cross-sectionally and symptoms of respiratory infection were investigated retrospectively for part of traders of three wholesale markets for wild animals in Guangzhou.

RESULTS: Overall rate of infection with SARS-CoV in 635 traders was 16.69%, varying in three different markets. Infection rate in market A mainly engaging in wild animals ranked the highest of 25.61%, significantly higher than that in markets B and C engaging in domestic fowls and snakes. Infection rate in traders only engaging in civet cats was 58.54%, significantly higher than that in traders engaging in snakes only (9.46%). In market A, infection rate varied in different persons, 59.34%, 20.59%, 16.00%, 15.22%, 10.40% and 9.68% in traders engaging in wild animals, managers, children of the traders, traders engaging in domestic fowls, traders engaging in snakes, and traders engaging in frozen food, respectively, in a decreasing pattern as their contact opportunities. During the period of SARS epidemic, detection rate of SARS-CoV antibody in people with symptoms of acute respiratory infection was higher (30.70%) than that in those without such symptoms (20.08%). Prevalence of symptoms of acute upper respiratory infection in people with positive antibody against SARS-CoV was higher (49.28%) than that in those with negative antibody (30.35%).

CONCLUSIONS: Infection with SARS-CoV in traders of animal markets possibly related to their direct exposure to wild animals, particularly to civet cats. During the period of SARS epidemic, some of the traders did infect with SARS-CoV, but they were neglected due to clinically inapparent manifestations.