Objective To understand the spatiotemporal distribution of human brucellosis in China in 2024, analyze the correlation between its incidence and infection level in both human and animals, and provide evidence for targeted prevention and control of human brucellosis.

Methods The incidence data of human brucellosis from China National Notifiable Disease Reporting System and serological surveillance data in both human and animals in 2024 were used for the descriptive epidemiological analysis on the time, space, and population (age, gender and occupation) distributions of human brucellosis. Spatial statistical methods, including spatial clustering analysis, were used to detect epidemic hotspot areas. Spearman's rank correlation test was conducted to evaluate the correlation between human incidence and infection levels in both human and animals.

Results In 2024, a total of 62 055 cases of human brucellosis were reported, with an incidence rate of 4.41/100 000, the cases decreased by 11.90% compared with 2023 (8 384/70 439). The incidence of the disease exhibited distinct gender, age and occupation specific characteristics, with the most cases being men, individuals in age groups 50～ years and 55～ years and farmers. A marked seasonal distribution was observed, the incidence peaked in spring and summer. Geographically, 89.73% of the cases (55 682/62 055) were reported in northern China, while 10.27% of the cases (6 373/62 055) were reported in southern China. Additionally, there were 1 195 counties with the incidence rate exceeding 2.0/100 000. Global spatial autocorrelation analysis revealed a positive spatial correlation in national brucellosis incidence (Moran's I = 0.236, P ≤ 0.05). Local spatial autocorrelation analysis identified distinct "high-high" clusters in northeastern, northern and northwestern China. The seroprevalence was 3.96% in 96 human surveillance areas in China in 2024 (2 172/54 851), with 6 237 newly confirmed cases. The seroprevalence in livestock surveillance was 0.24% in cattle (5 127/2 151 173) and 0.59% in sheep/goats (4 866/ 828 790).

Conclusion The incidence of human brucellosis showed obvious age, season and area distributions in China. Given the high heterogeneity in seropositive rates from human and animal surveillance, it is suggested to reallocate more resources toward animal brucellosis prevention and control and strengthen source control based on livestock surveillance and disinfection.