Abstract:

Objective To analyze the spatiotemporal distribution characteristics of hemorrhagic fever with renal syndrome (HFRS) in Chuxiong Yi Autonomous Prefecture, Yunnan Province, so as to provide a basis for scientific prevention and control of infection. Methods HFRS case data reported from 2012 to 2023 in Chuxiong Prefecture were retrieved from the Infectious Disease Surveillance System of Chinese Disease Prevention and Control Information System. Host animal surveillance data for 2021 were obtained from Chuxiong Prefecture Center for Disease Control and Prevention. Descriptive analysis was conducted on the characteristics of time, region and population for HFRS, as well as on the surveillance results of its host animals. Joinpoint regression model was used to analyze the incidence trend. Spatial information visualization techniques and kernel density estimation were used to evaluate the spatiotemporal clustering characteristics of cases. Results A total of 1 131 HFRS cases and 2 deaths were reported in Chuxiong Prefecture during 2012-2023. The annual incidence rate fluctuated between 0.41/100 000 and 8.18/100 000, showing an overall upward trend (AAPC=34.37%, t=3.74, P<0.01). More cases were reported from March to July (n=583; 51.55%). The cases were mainly distributed in Yao’an County, Chuxiong City, and Lufeng City, accounting for 77.54% (877/1 131) of total cases. The incidence rate in Yao’an County showed a continuous increase from 2012 to 2023 (APC=AAPC=62.45%, t=13.26, P<0.01), while Chuxiong City demonstrated a declining trend after 2018 (APC=-25.30%, t=-2.42, P<0.05). Spatiotemporal hotspots evolved from Lucheng Town and Donggua Town in Chuxiong City to Dongchuan Town and surrounding townships in Yao’an County. The average annual incidence rate was higher in males (4.88/100 000) than in females (2.16/100 000). The majority of cases were farmers (n=837; 74.00%). The median age of cases was 50.0 (38.0, 61.0) years, with the age at onset increasing from 40.0 (32.0, 56.0) years in 2012 to 57.0 (48.0, 68.0) years in 2023. In 2021, the average rodent density was 3.01%, with Rattus norvegicus (64.00%) and Rattus flavipectus (21.09%) being the dominant species. The hantavirus infection rate in rodents was 14.74% (158/1 072). Conclusion The incidence of HFRS in Chuxiong Prefecture showed obvious spatiotemporal clustering. Males, farmers, and population over 50 years old were most affected, and the age at disease onset showed a yearly increasing trend. The findings suggest that host animal control and prevention measures for key populations should be strengthened during high-incidence seasons.

Key words: Hemorrhagic fever with renal syndrome, Spatiotemporal distribution, Hantavirus, Host animal surveillance, Chuxiong Yi Autonomous Prefecture