Surveillance results of hemorrhagic fever with renal syndrome in Liaoning, 2016−2020

  Objective  To analyze the epidemiological characteristics and change trend of hemorrhagic fever with renal syndrome (HFRS) in Liaoning province and provide scientific basis for the development of prevention and control measures.

  Methods  The incidence data of HFRS and population data in Liaoning from 2016 to 2020 were collected from China Infectious Disease Surveillance Information System. Gene typing and antibody level of the selected samples were detected by nested RT-PCR and enzyme-linked immunosorbent assay (ELISA). The dynamic characteristics of monthly, regional and population distribution of HFRS in Liaoning were analyzed by descriptive epidemiological method.

  Results  From 2016 to 2020, the annual average incidence rate of HFRS in Liaoning was 1.98/100 000, the incidence rate fluctuated between 1.05/100 000 and 2.53/100 000, and the annual average mortality rate was 0.0064/100 000. The cases were mainly occurred in Huludao, Jinzhou and Chaoyang in western Liaoning and Tieling, Fushun and Benxi in eastern Liaoning. The incidence peak of HFRS was during spring-summer (February-June) and during autumn-winter (October-December), the cases accounted for 79.78% of the total reported cases. There was only one incidence peak during spring-summer in Huludao, Jinzhou, Chaoyang, Panjin and Fuxin, only one incidence peak during autumn-winter in Dandong, Anshan and Liaoyang , the autumn winter peak was higher than the spring summer peak in Fushun, Tieling and Benxi, and the spring summer peak was higher than the autumn winter peak in Dalian, Yingkou and Shenyang. In terms of population distribution, the male to female ratio of the cases was 2.51∶1, the cases were mainly farmers. The cases in age group of 25−69 years old accounted for 87.40%, and the recessive infection rate was 5.50%. The distribution of hantavirus genotypes in different areas showed different characteristics. Only Seoul genotype was detected in 5 areas in western Liaoning; Seoul genotype and Hantan genotype were detected in other 9 areas.

  Conclusion  The incidence rate of HFRS in Liaoning fluctuated slightly from 2016 to 2020. Liaoning was a mixed epidemic area of Hantan type virus and Seoul type virus, the seasonality of the predominant virus was more obvious; It is suggested to develop targeted prevention and control measures based on the epidemiological characteristics of HFRS in different areas.