Epidemiological characteristics of influenza in Mianyang, Sichuan, 2019-2021
- Author:
WEN Yan
;
CHEN Hua
;
LIU Shi-an
;
YANG Xiao-rong
;
CHEN Guo
;
DAI Yu-ke
- Publication Type:Journal Article
- Keywords:
Influenza;
influenza-like illness cases;
epidemiological characteristics;
etiology surveillance;
outbreak
- From:
China Tropical Medicine
2023;23(1):64-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To understand the epidemiological and etiological characteristics of influenza in Mianyang City
from 2019 to 2021, so as to provide a basis for the prevention and control of influenza. Methods Influenza surveillance data
in Mianyang City from 2019 to 2021 were collected and analyzed statistically. Results A total of 55 970 cases of influenza
were reported in Mianyang City from 2019 to 2021, with an average annual incidence of 388.08/100 000. A total of 103 723
cases of influenza -like illness cases (ILI) were reported, with an average annual ILI% of 3.58%. The incidence, ILI% , and
positive detection rates of influenza were all far higher than those in the corresponding period in 2019. The classification of the
population is mainly composed of students under the age of 15. The top three reported cases were Fucheng District (20 118,
35.94%), Youxian District (6 394, 11.42%) and Jiangyou District (5 800, 10.36%). 10 126 samples of ILI were received and
detected, with a positive rate of 19.53%, the positive rate of ILI samples was mainly students under 15 years old. The dominant
strains of influenza viruses showed an alternating trend over the years, and A (H3) was the predominant type in 2019. Except for
2 A (H9) strains detected in 2021, the rest were all BV strains. Due to the impact of COVID-19 in 2020, the positive detection
rate was low throughout the year. 43 outbreaks of ILI were reported, which were mainly occurred in winter, and most of them
were in primary schools. Conclusion From 2019 to 2021, the characteristics of cases, ILI, pathogen surveillance and
outbreak events of influenza in Mianyang City are basically the same, with students under 15 years of age and schools
remaining the key population and sites of concern. the importance of non-pharmaceutical interventions for influenza prevention
and control is further evidenced by the low incidence of influenza during the COVID-19 pandemic.
- Full text:12.Epidemiological characteristics of influenza in Mianyang, Sichuan, 2019-2021.pdf
