Abstract:

Objective To understand the epidemiological characteristics of hemorrhagic fever with renal syndrome（HFRS） in Tianjin from 2000 to 2024 and predict the epidemic trend for the next three years，thereby providing a basis for future prevention and control efforts. Methods The descriptive epidemiological method was conducted on the surveillance data of HFRS in Tianjin from 2000 to 2024，and the auto-regressive moving average model（ARIMA） model was used to predict the incidence trend for the next two years. Results From 2000 to 2024，a total of 1 944 HFRS cases were reported in Tianjin，with 26 deaths，the average annual incidence rate was 0.57/100 000. A significant peak in cases occurred between 2000 and 2002，with the number of cases reported during these three years accounting for 49.9% of the total cases. Subsequently，the epidemic declined rapidly，entering a period of low-level fluctuations since 2007. The annual incidence rate of HFRS in Tianjin had remained consistently below 0.1/100 000 since 2019，with no death. Joinpoint regression analysis showed that the overall incidence of HFRS in Tianjin showed a downward trend（APC=-15.3%，95%CI：-18.3%- -12.1%，P<0.01），the decline rate changed in 2004 and 2007，and the decline trend was faster during 2004-2007. The decline trend during 2007-2024 was slower than that in 2000-2004. The incidence showed a bimodal pattern of small winter peak and big spring peak. The seasonal index from January to June was >1，the disease became a winter single peak（November to January of the following year） since 2019，and the number of months with seasonal index >1 also decreased to 3 months. Areas with high incidence of diseases had gradually shifted from urban areas to rural areas. The number of cases in men was significantly higher than that of women，and the sex ratio was 3.6 ∶ 1. The cases aged 30-<50 years old accounted for 50.3% of the total cases，and the occupational distribution was dominated by farmers（33.1%）. The index of rat density and rat toxicity showed a downward trend，and the carry virus index of rat was positively correlated with the incidence of epidemic hemorrhagic fever（r=0.732，P<0.01）. The ARIMA model predicted that the incidence of HFRS in Tianjin would remain steadily low in the next 3 years. Conclusion The HFRS epidemic in Tianjin will continue to maintain a steadily low state，but due to the characteristics of natural epidemic diseases，the relevant monitoring work still needs to be carried out for a long time to grasp the changes in the disease. At the same time，new technologies and new methods should be actively explored to improve the monitoring efficiency.

Key words: Hemorrhagic fever with renal syndrome, Epidemic characteristics, Seasonal index, Trend prediction, Prevention and control