key: cord-0030510-p09sbxhn
authors: Wang, Qiang; Yang, Liuqing; Liu, Chang; Jin, Hui; Lin, Leesa
title: Estimated Incidence of Seasonal Influenza in China From 2010 to 2020 Using a Multiplier Model
date: 2022-04-14
journal: JAMA Netw Open
DOI: 10.1001/jamanetworkopen.2022.7423
sha: e0ead2c11ba1737332e2e2c4ea27136be89f0a08
doc_id: 30510
cord_uid: p09sbxhn

This quality improvement study estimates the total incidence of seasonal influenza and associated illnesses in China from 2010 to 2020.

Nine proportions are needed in the model, including the proportion of symptomatic cases among the total number of influenza virus infections (A); proportion of individuals with symptomatic infections seeking health care (B); proportion of symptomatic illnesses seeking health care seen at national sentinel hospitals (C); proportion of individuals with influenza who fulfilled the definition of ILI (D); proportion of patients with ILI that accept specimen collection (E); proportion of specimens collected successfully (F); proportion of specimens delivered and tested in a timely manner (G); test sensitivity (H); and proportion of positive specimens reported in a timely manner (I) (eTable 1).

A and H were based on previous systematic reviews. 5, 6 B, C, and E were obtained through metaanalyses that pooled data after performing a literature search of the Chinese and English literature. For B, ten of 60 studies reviewed in full text provided data about the likelihood of individuals with ILI seeking health care, and the extracted data were pooled according to age group to obtain age-specific estimates. The pooled rate among individuals aged 0-14 years, 15-59 years, and ≥60 years was estimated to be 76.03%, 58.14%, and 72.00%, respectively. In the process of finding and extracting C, 2,450 articles were identified, and the full texts of 50 articles were reviewed. Finally, only one study in Suzhou city was used to obtain estimates of the proportion of individuals with ILI that sought health care at national sentinel hospitals who were aged between 0-14 years, and the rate was 28.32% which 492 repeated articles and 1,394 unrelated articles were excluded, and 69 articles were finally included after reviewing 444 articles. The proportion of individuals with ILI that accepted specimen collecting was pooled by season. The pooled rates ranged from 10.34% to 23.84% across the ten influenza seasons between 2010 and 2020. Search strategies and flowcharts of the meta-analyses are shown below (eFigure 1-3). D and F were derived from a previous multiplier model study. 9 year, and ≥60 year age groups, respectively.

The number of infections was estimated for the following age groups: children (0-14 years), E: Proportion of individuals with an influenza ill-likeness who accepted specimen collection eFigure 1. Flowchart of study selection for proportion B a a search strategy: We used the following search terms: "influenza" OR "influenza like illness" OR "influenza-like illness"

OR "ILI" AND "seeking behaviour*" OR "seek" AND "China". A systematic search of the available medical literature was performed on October 07, 2021, using Chinese language databases including China National Knowledge Infrastructure, Chinese Science and Technology Periodical Database, and WanFang Database, and English language databases including PubMed, and Web of Science.

A ten-year China-US laboratory collaboration: improving response to influenza threats in China and the world

National Influenza Surveillance Technical Guide

Estimates of the prevalence of pandemic (H1N1) 2009, United States

Estimated incidence and number of outpatient visits for seasonal influenza in 2015-2016 in Beijing

Time lines of infection and disease in human influenza: a review of volunteer challenge studies

Multiplex PCR system for the rapid diagnosis of respiratory virus infection: systematic review and meta-analysis

Influenza-associated outpatient visits among children less than 5 years of age in eastern China

Attitudes, and Behaviors (KAB) of Influenza Vaccination in China: A Cross-Sectional Study in

Estimates of the true number of cases of pandemic (H1N1)

Southeast University (master dissertation)

Meta analysis F: Proportion of specimens that were collected successfully 80%

G: Proportion of specimens that were delivered and tested timeously 90%