Influenza vaccine effectiveness (VE) has to be estimated anew for every season to explore vaccines' protective effect in the population. We report VE estimates against laboratory-confirmed influenza A(H1N1)pdm09, A(H3N2) and influenza B among children aged 2-17 years, using test-negative design. Pooled data from two German federal states' surveillance systems for acute respiratory illness from week 40/2012 to 20/2016 was used, yielding a total of 10 627 specimens. Odds ratios and 95% confidence intervals (95% CIs) for the association between laboratory-confirmed influenza and vaccination status were calculated by multivariate logistic regression adjusting for age, sex, illness onset and federal state. VE was estimated as 1-Odds Ratio. Overall adjusted VE was 33% (95% CI: 24·3-40·7). A strong variation of VE between the seasons and subtypes was observed: highest season- and subtype-specific VE of 86·2% (95% CI: 41·3-96·7) was found against A(H1N1)pdm09 in 7-17-year-olds in 2015/16. Low estimates of VE were observed against A(H3N2) in any season, e.g. 1·5% (95% CI: -39·3-30·3) in 2014/15. Estimates showed a tendency to higher VE among 7-17-year-old children, but differences were not statistically significant. Although our findings are common in studies estimating influenza VE, we discussed several explanations for observed low VE.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9134507PMC
http://dx.doi.org/10.1017/S0950268817002709DOI Listing

Publication Analysis

Top Keywords

laboratory-confirmed influenza
12
vaccine effectiveness
8
influenza children
8
influenza
6
95%
5
estimating vaccine
4
effectiveness laboratory-confirmed
4
children adolescents
4
adolescents lower
4
lower saxony
4

Similar Publications

Background: Seasonal influenza illness and acute respiratory infections can impose a substantial economic burden in low- and middle-income countries (LMICs). We assessed the cost of influenza illness and acute respiratory infections across household income strata.

Methods: We conducted a secondary analysis of data from a prior systematic review of costs of influenza and other respiratory illnesses in LMICs and contacted authors to obtain data on cost of illness (COI) for laboratory-confirmed influenza-like illness and acute respiratory infection.

View Article and Find Full Text PDF

High quality research is critical for evidence-based decision making in public health and fundamental to maintain progress and trust in immunization programs in Europe. In 2024 the European Centre for Disease Prevention and Control (ECDC) conducted an update of the 2020 systematic review to capture more recent evidence on of the efficacy, effectiveness of influenza vaccines in individuals aged 18 years and older in the prevention of laboratory-confirmed influenza. While this report was highly anticipated due to the strength of the protocol and processes put in place, during our assessment, we expressed two chief concerns.

View Article and Find Full Text PDF

Highly Pathogenic Avian Influenza A(H5N1) Virus Infections in Humans.

N Engl J Med

December 2024

From the Influenza Division, Centers for Disease Control and Prevention, Atlanta (S.G., K.R., A.C., K.K., C.T.D., M.K.K., S. Ellington, A.M.M., A.B., J.R.B., M.B., M.A.J., M.R.-C., E.B., T.T.S., T.M.U., V.G.D., C.R., S.J.O.); California Department of Public Health, Richmond (E.L.M., S.Z., V.K., D.A.W.); the Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta (S.Z., C.D.); Colorado Department of Public Health and Environment, Denver (C.D., A.K., M.O.); Mid-Michigan District Health Department, Stanton (J.M.); Michigan Department of Health and Human Services, Lansing (S. Eckel); Missouri Department of Health and Senior Services, Jefferson City (J.G., G.T.); Benton-Franklin Health District, Kennewick, WA (S.K.); Washington State Department of Health, Tumwater (A.U.); and Texas Department of State Health Services, Austin (E.R.G., C.A.H.).

Background: Highly pathogenic avian influenza A(H5N1) viruses have caused widespread infections in dairy cows and poultry in the United States, with sporadic human cases. We describe characteristics of human A(H5N1) cases identified from March through October 2024 in the United States.

Methods: We analyzed data from persons with laboratory-confirmed A(H5N1) virus infection using a standardized case-report form linked to laboratory results from the Centers for Disease Control and Prevention influenza A/H5 subtyping kit.

View Article and Find Full Text PDF

Moderate effectiveness of influenza vaccine in outpatient settings: A test-negative study in Beijing, China, 2023/24 season.

Vaccine

December 2024

Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control, Beijing, China; Beijing Research Center for Respiratory Infectious Diseases, Beijing, China. Electronic address:

Introduction: The objective of our study was to estimate the influenza vaccine effectiveness for 2023/24 epidemic of co-circulating influenza A(H3N2) and B(Victoria) viruses in Beijing, China.

Methods: The surveillance-based study included all swabbed patients through influenza virological surveillance in Beijing, between October 2023 and March 2024. A Test-Negative Design(TND) was used to estimate influenza vaccine effectiveness(VE) against medically- attended laboratory-confirmed influenza in outpatient settings, also calculated the influenza vaccination rate(IVR).

View Article and Find Full Text PDF

Background: Prior studies have reported lower effectiveness of XBB.1.5-adapted vaccines against hospitalization related to the Omicron JN.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!