Abstract
Brucellosis remains a serious public health issue in developing countries, including China. On August 8, 2013, four cases of brucellosis from one extended family were reported at Shuyang County, Jiangsu Province, China. Active case finding was performed to identify the source and the risk factors of the infection and to prevent additional cases. Multiple-locus variable number tandem repeat analysis (MLVA) was used for molecular subtyping analysis. Six people from two extended families met the case definition for brucellosis infection; four were blood culture positive for Brucella melitensis biotype 3. Four additional family members were found seropositive by using a serological test. Isolates from the four patients were indistinguishable by MLVA profiling, displaying a unique type for Jiangsu Province. Field epidemiological data combined with MLVA genotyping supported a common source of the isolates from the different patients. We recommend stronger reinforcement measures for animal quarantine practices, enhanced cooperation with veterinary service organizations, and implementation of measures that strengthen public education on brucellosis to prevent further human outbreaks in Jiangsu Province.