Epidemiology of brucellosis in Hunyuan county in Shanxi province,2004 - 2009

Objective To understand the epidemiological characteristics of brucellosis in Hunyuan from 2004 to 2009 and provide evidence for the local prevention and control of brucellosis. Methods The analysis on incidence data of brucellosis during this period was conducted to know the regional, age, sex and occupation distributions of the disease. Rose bengal plate agglutination test (RBPA) and standard tube agglutination test (STA) were performed to detect 79 serum samples collected from outpatients, and bacterial culture was performed for 11 blood samples collected from fever patients. Results From 2004 to 2009,58,99,158,232,188 and 171 cases were detected respectively (the total:906). Up to 639 cases occurred in the people aged 30-60 years, accounting for 69.76%, and 286 cases occurred in the people aged 50 to 60 years, accounting for 31.22%. The case number was 733 for males (80.02%) and 173 for females (19.09%). Totally 805 cases were farmers (87.89%). The case numbers in Yongan and Shagetuo were 143 and 112 respectively, which were significantly higher than other townships. The case numbers in restaurant workers and students increased from 0 and 1 to 7 and 8 respectively. Among the 79 serum samples 57 were both RBPT and STA positive,59 were RBPT positive and 58 were STA positive respectively. Two strains of Brucella melitensis Ⅲ were isolated from the 11 blood samples, which were identified by Institute for Communicable Disease Control and Prevention, China CDC. Conclusion The overall incidence of brucellosis increased in all 18 townships in Hunyuan county from 2004 to 2009. The disease affected all age groups, but mainly middle-age group. More cases were reported in males than females. Farmers were the mostly affected population. The cases in students and restaurant workers had increased. Brucella melitensis Ⅲ is the prevalent strain in Hunyuan.