2015/16 seasonal vaccine effectiveness against hospitalisation with influenza A(H1N1)pdm09 and B among elderly people in Europe: results from the I-MOVE+ project

We conducted a multicentre test-negative case–control study in 27 hospitals of 11 European countries to measure 2015/16 influenza vaccine effectiveness (IVE) against hospitalised influenza A(H1N1)pdm09 and B among people aged ≥ 65 years. Patients swabbed within 7 days after onset of symptoms compatible with severe acute respiratory infection were included. Information on demographics, vaccination and underlying conditions was collected. Using logistic regression, we measured IVE adjusted for potential confounders. We included 355 influenza A(H1N1)pdm09 cases, 110 influenza B cases, and 1,274 controls. Adjusted IVE against influenza A(H1N1)pdm09 was 42% (95% confidence interval (CI): 22 to 57). It was 59% (95% CI: 23 to 78), 48% (95% CI: 5 to 71), 43% (95% CI: 8 to 65) and 39% (95% CI: 7 to 60) in patients with diabetes mellitus, cancer, lung and heart disease, respectively. Adjusted IVE against influenza B was 52% (95% CI: 24 to 70). It was 62% (95% CI: 5 to 85), 60% (95% CI: 18 to 80) and 36% (95% CI: -23 to 67) in patients with diabetes mellitus, lung and heart disease, respectively. 2015/16 IVE estimates against hospitalised influenza in elderly people was moderate against influenza A(H1N1)pdm09 and B, including among those with diabetes mellitus, cancer, lung or heart diseases.

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Age-specific vaccine effectiveness of seasonal 2010/2011 and pandemic influenza A(H1N1) 2009 vaccines in preventing influenza in the United Kingdom

Epidemiology and Infection ◽

10.1017/s0950268812001148 ◽

2012 ◽

Vol 141 (3) ◽

pp. 620-630 ◽

Cited By ~ 30

Author(s):

R. G. PEBODY ◽

N. ANDREWS ◽

D. M. FLEMING ◽

J. McMENAMIN ◽

S. COTTRELL ◽

...

Keyword(s):

Influenza Vaccine ◽

Pandemic Influenza ◽

Influenza A ◽

Vaccine Effectiveness ◽

Influenza B ◽

The United Kingdom ◽

Previous Season ◽

Negative Case ◽

Influenza A H1n1 ◽

Control Study

SUMMARYAn analysis was undertaken to measure age-specific vaccine effectiveness (VE) of 2010/11 trivalent seasonal influenza vaccine (TIV) and monovalent 2009 pandemic influenza vaccine (PIV) administered in 2009/2010. The test-negative case-control study design was employed based on patients consulting primary care. Overall TIV effectiveness, adjusted for age and month, against confirmed influenza A(H1N1)pdm 2009 infection was 56% (95% CI 42–66); age-specific adjusted VE was 87% (95% CI 45–97) in <5-year-olds and 84% (95% CI 27–97) in 5- to 14-year-olds. Adjusted VE for PIV was only 28% (95% CI −6 to 51) overall and 72% (95% CI 15–91) in <5-year-olds. For confirmed influenza B infection, TIV effectiveness was 57% (95% CI 42–68) and in 5- to 14-year-olds 75% (95% CI 32–91). TIV provided moderate protection against the main circulating strains in 2010/2011, with higher protection in children. PIV administered during the previous season provided residual protection after 1 year, particularly in the <5 years age group.

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Prevention of Influenza Hospitalization Among Adults in the United States, 2015–2016: Results From the US Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN)

The Journal of Infectious Diseases ◽

10.1093/infdis/jiy723 ◽

2018 ◽

Vol 220 (8) ◽

pp. 1265-1275 ◽

Cited By ~ 19

Author(s):

Jill M Ferdinands ◽

Manjusha Gaglani ◽

Emily T Martin ◽

Don Middleton ◽

Arnold S Monto ◽

...

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

The United States ◽

Vaccine Effectiveness ◽

Severe Illness ◽

Influenza B Virus ◽

Influenza B ◽

Negative Case ◽

Influenza A H1n1 ◽

The Us

Abstract Background Evidence establishing effectiveness of influenza vaccination for prevention of severe illness is limited. The US Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN) is a multiyear test-negative case-control study initiated in 2015–2016 to estimate effectiveness of vaccine in preventing influenza hospitalization among adults. Methods Adults aged ≥18 years admitted to 8 US hospitals with acute respiratory illness and testing positive for influenza by polymerase chain reaction were cases; those testing negative were controls. Vaccine effectiveness was estimated with logistic regression adjusting for age, comorbidities, and other confounding factors and stratified by frailty, 2-year vaccination history, and clinical presentation. Results We analyzed data from 236 cases and 1231 controls; mean age was 58 years. More than 90% of patients had ≥1 comorbidity elevating risk of influenza complications. Fifty percent of cases and 70% of controls were vaccinated. Vaccination was 51% (95% confidence interval [CI], 29%–65%) and 53% (95% CI, 11%–76%) effective in preventing hospitalization due to influenza A(H1N1)pdm09 and influenza B virus infection, respectively. Vaccine was protective for all age groups. Conclusions During the 2015–2016 US influenza A(H1N1)pdm09–predominant season, we found that vaccination halved the risk of influenza-association hospitalization among adults, most of whom were at increased risk of serious influenza complications due to comorbidity or age.

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Poor Vaccine Effectiveness against Influenza B-Related Severe Acute Respiratory Infection in a Temperate North Indian State (2019–2020): A Call for Further Data for Possible Vaccines with Closer Match

Vaccines ◽

10.3390/vaccines9101094 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1094

Author(s):

Hyder Mir ◽

Inaamul Haq ◽

Parvaiz A. Koul

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

Respiratory Illness ◽

Vaccine Effectiveness ◽

Influenza Viruses ◽

Vaccine Uptake ◽

Influenza B ◽

Severe Acute Respiratory Infection ◽

Influenza A H1n1 ◽

Indian State

Influenza vaccine uptake in India is poor, and scant data exist regarding the effectiveness of influenza vaccine against hospitalization. Methods: From October 2019 to March 2020, vaccination status of 1219 patients (males n = 571, aged 5–107 years; median, 50 years) hospitalized with severe acute respiratory illness (SARI) was assessed. The patients were tested for influenza viruses and their subtypes by RT PCR. Sequencing of the HA gene was performed. Vaccine effectiveness (VE) against influenza subtypes was estimated by the test negative design. Results: A total of 336 (27.5%) patients were influenza-positive, with influenza B/Victoria accounting for 49.7% (n = 167), followed by influenza A/H1N1 (47.6%; n = 155) and influenza A/H3N2 (4.4%; n = 15). About 6.8% and 8.6% of the influenza-positive and influenza-negative patients, respectively, had been vaccinated. Adjusted VE for any influenza strain was 13% (95% CI −42 to 47), which for influenza B was 0%. HA sequencing revealed that influenza B samples mainly belonged to subclade V1A.3/133R with deletion of residues 163–165, as against the 2-aa deletion in influenza B/Colorado/06/2017 strain, contained in the vaccine. VE for influenza A/H1N1 was 55%. Conclusions: Poor VE due to a genetic mismatch between the circulating strain and the vaccine strain calls for efforts to reduce the mismatch.

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Influenza vaccine effectiveness in adults 65 years and older, Denmark, 2015/16 – a rapid epidemiological and virological assessment

Eurosurveillance ◽

10.2807/1560-7917.es.2016.21.14.30189 ◽

2016 ◽

Vol 21 (14) ◽

Cited By ~ 16

Author(s):

Hanne Dorthe Emborg ◽

Tyra Grove Krause ◽

Lene Nielsen ◽

Marianne Kragh Thomsen ◽

Claus Bohn Christiansen ◽

...

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

Control Design ◽

Case Control ◽

Vaccine Effectiveness ◽

Influenza B ◽

Trivalent Influenza Vaccine ◽

Negative Case ◽

Influenza A H1n1 ◽

Genetic Subgroup

In Denmark, both influenza A(H1N1)pdm09 and influenza B co-circulated in the 2015/16 season. We estimated the vaccine effectiveness (VE) of the trivalent influenza vaccine in patients 65 years and older using the test-negative case–control design. The adjusted VE against influenza A(H1N1)pdm09 was 35.0% (95% confidence interval (CI): 11.1–52.4) and against influenza B 4.1% (95% CI: −22.0 to 24.7). The majority of influenza A(H1N1)pdm09 circulating in 2015/16 belonged to the new genetic subgroup subclade 6B.1.

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Inactivated influenza vaccine effectiveness among department of defense beneficiaries aged 6 months-17 years, 2016–2017 through 2019–2020 influenza seasons

PLoS ONE ◽

10.1371/journal.pone.0256165 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256165

Author(s):

Wenping Hu ◽

Laurie S. DeMarcus ◽

Paul A. Sjoberg ◽

Anthony S. Robbins

Keyword(s):

Influenza Vaccine ◽

Department Of Defense ◽

Influenza A ◽

Linear Mixed Model ◽

Vaccine Effectiveness ◽

Respiratory Pathogen ◽

Surveillance Program ◽

Influenza B ◽

Negative Case ◽

Influenza A H1n1

A test-negative case-control study was conducted to assess inactivated influenza vaccine effectiveness (VE) in children aged 6 months-17 years. The database was developed from the US Department of Defense Global Respiratory Pathogen Surveillance Program over four consecutive influenza seasons from 2016 to 2020. A total of 9,385 children including 4,063 medically attended, laboratory-confirmed influenza-positive cases were identified for VE analysis. A generalized linear mixed model with logit link and binomial distribution was used to estimate the VE. The adjusted VE for children was 42% [95% confidence interval (CI): 37–47%] overall, including 55% (95% CI: 47–61%) for influenza A(H1N1)pdm09, 37% (95% CI: 28–45%) for influenza A(H3N2), and 49% (95% CI: 41–55%) for influenza B. The analysis by age groups indicated that the adjusted VE in children aged 6 months-4 years was higher against influenza A(H1N1)pdm09 and influenza B, and comparable against influenza A(H3N2), compared to those in children aged 5–17 years. Further age-stratified analysis showed that the VE against any types of influenza was low and non-significant for children aged 6–11 months (33%; 95% CI:-2-56%), but it was high (54%; 95% CI: 34–67%) in children aged 12–23 months, and then declined linearly with increasing age. In conclusion, the inactivated influenza vaccination was moderately effective against influenza infection, based on the analysis from a large number of children aged 6 months-17 years over multiple influenza seasons.

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Estimating vaccine effectiveness against laboratory-confirmed influenza among children and adolescents in Lower Saxony and Saxony-Anhalt, 2012–2016

Epidemiology and Infection ◽

10.1017/s0950268817002709 ◽

2017 ◽

Vol 146 (1) ◽

pp. 78-88 ◽

Cited By ~ 2

Author(s):

A. MÖHL ◽

L. GRÄFE ◽

C. HELMEKE ◽

D. ZIEHM ◽

M. MONAZAHIAN ◽

...

Keyword(s):

Influenza A ◽

Respiratory Illness ◽

Vaccine Effectiveness ◽

Federal State ◽

Influenza B ◽

Surveillance Systems ◽

Lower Saxony ◽

Federal States ◽

German Federal States ◽

Influenza A H1n1

SUMMARYInfluenza 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.

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Influenza vaccine effectiveness against laboratory-confirmed influenza in hospitalised adults aged 60 years or older, Valencia Region, Spain, 2017/18 influenza season

Eurosurveillance ◽

10.2807/1560-7917.es.2019.24.31.1800461 ◽

2019 ◽

Vol 24 (31) ◽

Author(s):

Ainara Mira-Iglesias ◽

F Xavier López-Labrador ◽

Víctor Baselga-Moreno ◽

Miguel Tortajada-Girbés ◽

Juan Mollar-Maseres ◽

...

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

Vaccine Effectiveness ◽

Influenza Viruses ◽

Influenza B ◽

Current Season ◽

Hospitalised Patients ◽

Influenza A H1n1 ◽

Vaccine Type ◽

The Impact

Introduction Influenza immunisation is recommended for elderly people each season. The influenza vaccine effectiveness (IVE) varies annually due to influenza viruses evolving and the vaccine composition. Aim To estimate, in inpatients ≥ 60 years old, the 2017/18 trivalent IVE, overall, by vaccine type and by strain. The impact of vaccination in any of the two previous seasons (2016/17 and 2015/16) on current (2017/18) IVE was also explored. Methods This was a multicentre prospective observational study within the Valencia Hospital Surveillance Network for the Study of Influenza and Respiratory Viruses Disease (VAHNSI, Spain). The test-negative design was applied taking laboratory-confirmed influenza as outcome and vaccination status as main exposure. Information about potential confounders was obtained from clinical registries and/or by interviewing patients; vaccine information was only ascertained by registries. Results Overall, 2017/18 IVE was 9.9% (95% CI: −15.5 to 29.6%), and specifically, 48.3% (95% CI: 13.5% to 69.1%), −29.9% (95% CI: −79.1% to 5.8%) and 25.7% (95% CI: −8.8% to 49.3%) against A(H1N1)pdm09, A(H3N2) and B/Yamagata lineage, respectively. For the adjuvanted and non-adjuvanted vaccines, overall IVE was 10.0% (95% CI: −24.4% to 34.9%) and 7.8% (95% CI: −23.1% to 31.0%) respectively. Prior vaccination significantly protected against influenza B/Yamagata lineage (IVE: 50.2%; 95% CI: 2.3% to 74.6%) in patients not vaccinated in the current season. For those repeatedly vaccinated against influenza A(H1N1)pdm09, IVE was 46.4% (95% CI: 6.8% to 69.2%). Conclusion Our data revealed low vaccine effectiveness against influenza in hospitalised patients ≥60 years old in 2017/18. Prior vaccination protected against influenza A(H1N1)pdm09 and B/Yamagata-lineage.

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Uptake and effectiveness of influenza vaccine in those aged 65 years and older in the United Kingdom, influenza seasons 2010/11 to 2016/17

Eurosurveillance ◽

10.2807/1560-7917.es.2018.23.39.1800092 ◽

2018 ◽

Vol 23 (39) ◽

Cited By ~ 10

Author(s):

Richard G Pebody ◽

Fiona Warburton ◽

Nick Andrews ◽

Mary Sinnathamby ◽

Ivelina Yonova ◽

...

Keyword(s):

United Kingdom ◽

Influenza Vaccine ◽

Influenza A ◽

Vaccine Uptake ◽

Attributable Mortality ◽

Influenza B ◽

Age Group ◽

The United Kingdom ◽

Negative Case ◽

Influenza A H1n1

Background In 2016/17, seasonal influenza vaccine was less effective in those aged 65 years and older in the United Kingdom. We describe the uptake, influenza-associated mortality and adjusted vaccine effectiveness (aVE) in this age group over influenza seasons 2010/11–2016/17. Methods: Vaccine uptake in 2016/17 and five previous seasons were measured using a sentinel general practitioners cohort in England; the test-negative case-control design was used to estimate pooled aVE by subtype and age group against laboratory-confirmed influenza in primary care from 2010–2017. Results: Vaccine uptake was 64% in 65–69-year-olds, 74% in 70–74-year-olds and 80% in those aged 75 and older. Overall aVE was 32.5% (95% CI: 11.6 to 48.5); aVE by sub-type was 60.8% (95% CI: 33.9 to 76.7) and 50.0% (95% CI: 21.6 to 68.1) against influenza A(H1N1)pdm09 and influenza B, respectively, but only 5.6% (95% CI: - 39.2 to 35.9) against A(H3N2). Against all laboratory-confirmed influenza aVE was 45.2% (95% CI: 25.1 to 60.0) in 65–74 year olds; - 26.2% (95% CI: - 149.3 to 36.0) in 75–84 year olds and - 3.2% (95% CI: - 237.8 to 68.5) in those aged 85 years and older. Influenza-attributable mortality was highest in seasons dominated by A(H3N2). Conclusions: Vaccine uptake with non-adjuvanted, normal-dose vaccines remained high, with evidence of effectiveness against influenza A(H1N1)pdm09 and B, though poor against A(H3N2), particularly in those aged 75 years and older. Forthcoming availability of newly licensed vaccines with wider use of antivirals can potentially further improve prevention and control of influenza in this group.

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2553. Individual Patient-Level Data Meta-Analysis of Live Attenuated and Inactivated Influenza Vaccine Effectiveness Among US Children, 2013–2014 Through 2015–2016

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy209.161 ◽

2018 ◽

Vol 5 (suppl_1) ◽

pp. S68-S68

Author(s):

Jessie Chung ◽

Brendan Flannery ◽

Rodolfo Begue ◽

Herve Caspard ◽

Laurie Demarcus ◽

...

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

The United States ◽

Vaccine Effectiveness ◽

Vaccination Status ◽

Influenza B ◽

Rt Pcr ◽

Current Season ◽

Influenza A H1n1 ◽

Vaccine Type

Abstract Background Quadrivalent live attenuated influenza vaccine (LAIV4) was not recommended for use in the United States for the 2016–2017 and 2017–2018 influenza seasons based on US observational studies of vaccine effectiveness (VE) from 2013–2014 to 2015–2016. We pooled individual patient data on children aged 2–17 years enrolled in 5 US studies during these 3 influenza seasons to further investigate VE by vaccine type. Methods Analyses included 17,173 children enrolled in the US Department of Defense Global Laboratory-based Influenza Surveillance Program, US Influenza Vaccine Effectiveness Network, Influenza Incidence Surveillance Project, Influenza Clinical Investigation for Children, and a Louisiana State University study. Participants’ specimens were tested for influenza by reverse transcription-polymerase chain reaction (RT-PCR), culture, or a combination of rapid antigen testing and RT-PCR. VE was calculated by comparing odds of vaccination with either inactivated influenza vaccine (IIV) or LAIV4 among influenza-positive cases to test-negative controls and calculated as 100 × (1 − odds ratio) in logistic regression models with age, calendar time, influenza season, and study site (random effect). Patients were stratified by prior season vaccination status in a subanalysis. Results Overall, 38% of patients (N = 6,558) were vaccinated in the current season, of whom 30% (N = 1,979) received LAIV4. Pooled VE of IIV against any influenza virus was 51% (95% CI: 47, 54) versus 26% (95% CI: 15, 36) for LAIV4. Point estimates for pooled VE against any influenza by age group ranged from 45% to 58% for IIV and 19% to 34% for LAIV4 during the 3 seasons (Figures 1 and 2). Pooled VE against influenza A(H1N1)pdm09 was 67% (95% CI: 62, 72) for IIV versus 20% (95% CI: −6, 39) for LAIV4. Pooled VE against influenza A(H3N2) was 29% (95% CI: 14, 42) for IIV versus 7% (95% CI: −11, 23) for LAIV4, and VE against influenza B was 52% (95% CI: 42, 60) for IIV and 66% (95% CI: 47, 77) for LAIV4. VE against influenza A(H1N1)pdm09 was lower for LAIV4 versus IIV across all strata of prior season vaccination (Figure 3). Conclusion Consistent with individual studies, our pooled analyses found that LAIV4 effectiveness was reduced for all age groups against influenza A(H1N1)pdm09 compared with IIV. This result did not vary based on prior vaccination status. Disclosures H. Caspard, AstraZeneca: Employee, Salary.

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