Analysis of epidemic characteristics and incidence trend of human brucellosis in Xining from 2019 to 2023

ZHANG Rui; MA Chunguang; WU Jing; TAO Yixin; SHEN Limei; YANG Xuxin; HE Shuzhen

doi:10.19821/j.1671-2781.2025.03.018

Abstract：Objective To investigate the epidemic characteristics and trends of human brucellosis in Xining from 2019 to 2023 and predict the trend of disease,so as to provide a scientific basis for the prevention and control of brucellosis.Methods Data of brucellosis cases reported online in Xining from 2019 to 2023 were collected.Excel2010 software was used to establish a database,and SPSS 25.0 software was used for descriptive analysis of the data.The byserological surveillance of high-risk occupational populations were conducted.The Joinpoint regression model was used to analyze the trend change.The linear trend fitting equation of time series was established to predict the incidence trend of brucellosis in the next 2 years.P＜0.05 was considered to be statistically significant.Results A total of 1 876 cases of brucellosis were reported in Xining from 2019 to 2023,the incidence ranged from 0.76/100 000 to 45.20/100 000,and the average annual incidence was 15.17/100 000.There was a linear increase in incidence in different years(x2trend=1 744.02,P＜0.001).Cases were reported in 7 counties(districts),and the top 3 with the reported cases were Datong County(684 cases),Huangzhong District(598 cases)and Huangyuan County(472 cases),accounting for 93.50％(1 754/1 876)of the total number of cases in the city.A total of 1 479 male and 397 female cases were reported,with a sex ratio of 3.73∶1.The average annual incidence in males was higher than that in females(x2=595.47,P＜0.001).The majority of cases were reported in the 30-69 year old group(1 616 cases,86.14％),and farmers and herdsmen(1 701 cases,90.67％).The incidence showed an upward trend from January to July[MPC=23.87(95％CI:8.38-41.56),t=3.79,P=0.007],and a downward trend from July to December[MPC=-26.76(95％CI:-38.62～-12.60),t=-4.17,P=0.004].There was a linear increasing trend in the positive rate of brucellosis serologic detection in high-risk occupational population(x2trend=17.006,P＜0.001).The linear trend fitting equation of the established time series was as follows:y=3.839t2-12.569t+10.641(R2=0.986),and the predicted incidences of human brucellosis in 2024 and 2025 were 73.43/100 000 and 110.77/100 000,respectively.Conclusion The incidence of human brucellosis in Xining shows a fluctuating upward trend,with obvious characteristics of incidence area,population and season.We should pay close attention to the change of epidemic trend,strengthen the active surveillance in key areas before the epidemic season,and coordinate the joint prevention and control mechanism with the cooperation of multiple departments.Comprehensive prevention and control measures such as medical staff training,standardized crowd screening,health education and behavioral intervention should continue,so as to effectively curb the growth of brucellosis.