Objective To analyze the incidence and spatial clustering of anthrax in Gansu province from 2014 to 2023, and to provide evidence for anthrax prevention and control.

Methods Data on 883 reported anthrax cases in Gansu province from January 1, 2014 to December 31, 2023 were collected through the “Surveillance and Reporting Management” module of the China Disease Prevention and Control Information System. The Joinpoint regression model was employed to analyze the trend of anthrax incidence. ArcGIS 10.8.2 and FleXScan 3.1.2 were used for global spatial autocorrelation and spatial scanning, respectively.

Results From 2014 to 2023, a total of 883 skin anthrax cases were reported in Gansu province. The number of cases in 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, and 2023 was 93, 104, 128, 117, 66, 41, 37, 84, 93, and 120, respectively. The incidences of anthrax were 0.36/100 000, 0.40/100 000, 0.49/100 000, 0.45/100 000, 0.25/100 000, 0.16/100 000, 0.14/100 000, 0.34/100 000, 0.35/100 000, and 0.48/100 000, respectively. The incidence increased first, subsequently decreased, and then increased, but the difference was not statistically significant (P > 0.05). Anthrax cases in Gansu province occurred throughout the year, and the peak of incidence occurred from July to October each year, when 501 cases were reported, accounting for 56.74% of the total number of anthrax cases. The ratio of male-to-female cases was 1.46:1. The disease predominantly affected young adults aged 20–49 (68.74%). The majority (82.33%) of cases occurred among herdsmen. The number of cases in Gannan prefecture ranked the first in the province (92.19%). The results of global spatial autocorrelation analysis showed that there was certain spatial clustering of anthrax incidence in Gansu province from 2014 to 2023. The global Moran′s I indices in 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, and 2023, were 0.438, 0.592, 0.590, 0.639, 0.577, 0.511, 0.530, 0.091, 0.565, and 0.357, respectively (all P < 0.05). FleXScan 3.1.2 software scanned 3 clusters, mainly located in some counties and districts of Gannan prefecture in the southwest of Gansu province and Dingxi city. The first-level cluster area included Maqu county, Luqu county, and Xiahe county in Gannan prefecture, mainly pastoral areas, accounting for 80.63% of the reported cases. Two secondary cluster areas were Hezuo city, Zhuoni county, and Diebu county in Gannan prefecture as well as Minxian county in Dingxi city and Lintan county in Gannan prefecture, accounting for 9.51% and 4.98% of cases, respectively.

Conclusions The incidence of anthrax in Gansu province from 2014 to 2023 was high and has increased in the past three years. Males, young adults, and herdsmen were the key populations for anthrax prevention and control. The primary cluster areas concentrated in Maqu county, Luqu county, and Xiahe county of Gannan prefecture in the southwest of Gansu province. It is necessary to conduct comprehensive monitoring in the aforementioned counties.