Epidemiological Characteristics of Human Brucellosis - China, 2016-2019.

Introduction Brucellosis is an important zoonotic infectious disease with its main mode of transmission from livestock to humans. The study analyzed epidemiological characteristics of human brucellosis from 2016 to 2019 in China, aiming to understand progress of the National Program of Brucellosis Prevention and Control. Methods The research obtained data on human brucellosis cases reported through China's National Notifiable Disease Reporting System (NNDRS) from January 1, 2016 to December 31, 2019 and described brucellosis epidemiological patterns by region, seasonality, age, sex, and occupation. Results The number of cases reported nationwide in China decreased from 47,139 (3.4/100,000) in 2016 to 37,947 (2.7/100,000) in 2018, and then increased to 44,036 (3.2/100,000) in 2019, with an average annual incidence of 3.0/100,000 during the four study years. Brucellosis in Xinjiang declined from 35.6/100,000 in 2016 to 16.3/100,000 in 2019 - an average annual decrease of 22.9%. Brucellosis in Inner Mongolia increased from 23.8/100,000 in 2016 to 54.4/100,000 in 2019 - an average increase of 31.8% per year and accounting for 22% of all reported cases. Northern China reported 95.2% of cases during this period and still had an incidence of 7.2/100,000 and 87.0% of counties being affected by brucellosis in 2019. In this region in 2019, males aged 45-64 years old had an incidence of over 15.9/100,000, compared with over 7.0/100,000 among females aged 45-64 years old. Conclusions lthough there was progress in prevention and control of human brucellosis in some provincial-level administrative divisions (PLADs) in 2016 through 2019, progress was limited nationwide and there was an overall resurgence of brucellosis in 2019. The resurgence was primarily in Inner Mongolia. An One Health approach should be strengthened to ensure successful and sustainable brucellosis prevention and control in China.