Serological surveillance for brucellosis among risk population in Cixi, Zhejiang, 2005-2013

Objective To understand the epidemiological characteristics of brucellosis among risk population with occupational exposure in Cixi, Zhejiang province and provide evidence for the development of prevention and control measures. Methods By using rose bengal plate agglutination test (RBPT) and standard tube agglutination test (SAT), serological detection was conducted among risk populations with occupational exposure to Brucella in Cixi, including those engaged in live stock raising, slaughtering, trade, milking as well as veterinary. Results From 2005 to 2013, 4230 persons received the detection, 56 were serological positive (1.32%), of which 31 were diagnosed with brucellosis and 25 were bacteria carriers. The brucellosis cases were mainly distributed in Zhouxiang and Zhangqi townships. The numbers of cases and carriers were highest in 2013 (11 and 6). The incidence of brucellosis was related with local goat trade, slaughtering and cow raising and with high incidence of brucellosis in areas from where cows and goats were imported. Most cases were young males. The average interval between onset and diagnosis was 3.5 months. The cases mainly occurred during February-May. Most cases were people with occupational exposure, but there were cases infected through contaminated food. Conclusion In recent years, the incidence of brucellosis showed a clear upward trend among risk population in Cixi. It is necessary to take comprehensive control measures, such as occupational protection and key link control. It is suggested to strengthen medical staff training on brucellosis diagnosis and management, conduct active surveillance among risk population and explore new prevention mechanism according to local conditions.