Effectiveness of Influenza Vaccines in the HIVE household cohort over 8 years: is there evidence of indirect protection?

AbstractBackgroundThe evidence that influenza vaccination programs regularly provide protection to unvaccinated individuals (i.e. indirect effects) of a community is lacking. We sought to determine the direct, indirect, and total effects of influenza vaccine in the Household Influenza Vaccine Evaluation (HIVE) cohort.MethodsUsing longitudinal data from the HIVE cohort from 2010-11 through 2017-18, we estimated direct, indirect, and total influenza vaccine effectiveness (VE) and the incidence rate ratio of influenza virus infection using adjusted mixed-effect Poisson regression models. Total effectiveness was determined through comparison of vaccinated members of full or partially vaccinated households to unvaccinated individuals in completely unvaccinated households.ResultsThe pooled, direct VE against any influenza was 30.2% (14.0-43.4). Direct VE was higher for influenza A/H1N1 43.9% (3.9 to 63.5) and B 46.7% (17.2 to 57.5) than A/H3N2 31.7% (10.5 to 47.8); and was higher for young children 42.4% (10.1 to 63.0) than adults 18.6% (−6.3 to 37.7). Influenza incidence was highest in completely unvaccinated households (10.6 per 100 person-seasons) and lower at all other levels of household vaccine coverage. We found little evidence of indirect VE after adjusting for potential confounders. Total VET was 56.4% (30.1-72.9) in low coverage, 43.2% (19.5-59.9) in moderate coverage, and 33.0% (12.1 to 49.0) in fully vaccinated households.ConclusionInfluenza vaccines may have a benefit above and beyond the direct effect but that effect in this study was small. While there may be exceptions, the goal of global vaccine recommendations should remain focused on provision of documented, direct protection to those vaccinated.

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Effects of Influenza Vaccination in the United States During the 2017–2018 Influenza Season

Clinical Infectious Diseases ◽

10.1093/cid/ciz075 ◽

2019 ◽

Vol 69 (11) ◽

pp. 1845-1853 ◽

Cited By ~ 78

Author(s):

Melissa A Rolfes ◽

Brendan Flannery ◽

Jessie R Chung ◽

Alissa O’Halloran ◽

Shikha Garg ◽

...

Keyword(s):

United States ◽

Influenza Vaccine ◽

Influenza Vaccination ◽

Influenza A ◽

Influenza Season ◽

Influenza Virus Infection ◽

The United States ◽

Influenza B ◽

Medical Visits ◽

Influenza A H1n1

Abstract Background The severity of the 2017–2018 influenza season in the United States was high, with influenza A(H3N2) viruses predominating. Here, we report influenza vaccine effectiveness (VE) and estimate the number of vaccine-prevented influenza-associated illnesses, medical visits, hospitalizations, and deaths for the 2017–2018 influenza season. Methods We used national age-specific estimates of 2017–2018 influenza vaccine coverage and disease burden. We estimated VE against medically attended reverse-transcription polymerase chain reaction–confirmed influenza virus infection in the ambulatory setting using a test-negative design. We used a compartmental model to estimate numbers of influenza-associated outcomes prevented by vaccination. Results The VE against outpatient, medically attended, laboratory-confirmed influenza was 38% (95% confidence interval [CI], 31%–43%), including 22% (95% CI, 12%–31%) against influenza A(H3N2), 62% (95% CI, 50%–71%) against influenza A(H1N1)pdm09, and 50% (95% CI, 41%–57%) against influenza B. We estimated that influenza vaccination prevented 7.1 million (95% CrI, 5.4 million–9.3 million) illnesses, 3.7 million (95% CrI, 2.8 million–4.9 million) medical visits, 109 000 (95% CrI, 39 000–231 000) hospitalizations, and 8000 (95% credible interval [CrI], 1100–21 000) deaths. Vaccination prevented 10% of expected hospitalizations overall and 41% among young children (6 months–4 years). Conclusions Despite 38% VE, influenza vaccination reduced a substantial burden of influenza-associated illness, medical visits, hospitalizations, and deaths in the United States during the 2017–2018 season. Our results demonstrate the benefit of current influenza vaccination and the need for improved vaccines.

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A Reduced-Dose Seasonal Trivalent Influenza Vaccine Is Safe and Immunogenic in Adult and Elderly Patients in a Randomized Controlled Trial

Clinical and Vaccine Immunology ◽

10.1128/cvi.05619-11 ◽

2012 ◽

Vol 19 (3) ◽

pp. 313-318 ◽

Cited By ~ 5

Author(s):

Zoltan Vajo ◽

Ferenc Tamas ◽

Istvan Jankovics

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

Seasonal Influenza ◽

Geometric Mean ◽

Influenza Vaccines ◽

Elderly Subjects ◽

Influenza B Virus ◽

Influenza B ◽

Reduced Dose ◽

Influenza A H1n1

ABSTRACTWith the recent pandemic of influenza A (H1N1) and vaccine shortages, there has been considerable interest in developing influenza vaccines with reduced doses, allowing for increased production capacity. Here we report a prospective, randomized, double-blind, single-center clinical trial of a reduced-dose whole-virion inactivated, adjuvanted influenza vaccine in adult and elderly volunteers. A total of 234 subjects, including 120 adults (18 to 60 years of age) and 114 elderly subjects (>60 years of age) were enrolled to receive either 6 μg or the conventional 15-μg dose of seasonal trivalent influenza vaccines. The subjects were followed for safety analysis, and serum samples were obtained to assess immunogenicity by hemagglutination inhibition testing. The subjects developed antibody responses against the seasonal influenza A virus H1N1 and H3N2 strains, as well as the seasonal influenza B virus included in the vaccines. Single doses of 6 μg fulfilled licensing criteria for seasonal influenza vaccines. No significant differences in rates of seroconversion or seroprotection or in geometric mean titers were found between the two dosage levels. All adverse events were rare, mild, and transient. We found that the present reduced-dose vaccine is safe and immunogenic in healthy adult and elderly subjects and triggers immune responses that comply with licensing criteria.

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Influenza Neuraminidase: A Neglected Protein and Its Potential for a Better Influenza Vaccine

Vaccines ◽

10.3390/vaccines8030409 ◽

2020 ◽

Vol 8 (3) ◽

pp. 409 ◽

Cited By ~ 1

Author(s):

Luca T. Giurgea ◽

David M. Morens ◽

Jeffery K. Taubenberger ◽

Matthew J. Memoli

Keyword(s):

Influenza Vaccine ◽

Influenza A ◽

Surface Protein ◽

Influenza Vaccines ◽

Infection Rates ◽

Viral Shedding ◽

Simple Strategy ◽

Decoy Receptors ◽

Influenza A H1n1 ◽

Infected Cells

Neuraminidase (NA) is an influenza surface protein that helps to free viruses from mucin-associated decoy receptors and to facilitate budding from infected cells. Experiments have demonstrated that anti-NA antibodies protect animals against lethal influenza challenge by numerous strains, while decreasing pulmonary viral titers, symptoms, and lung lesions. Studies in humans during the influenza A/H3N2 pandemic and in healthy volunteers challenged with influenza A/H1N1 showed that anti-NA immunity reduced symptoms, nasopharyngeal viral shedding, and infection rates. Despite the benefits of anti-NA immunity, current vaccines focus on immunity against hemagglutinin and are not standardized to NA content leading to limited and variable NA immunogenicity. Purified NA has been shown to be safe and immunogenic in humans. Supplementing current vaccines with NA may be a simple strategy to improve suboptimal effectiveness. Immunity against NA is likely to be an important component of future universal influenza vaccines.

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Effectiveness of influenza vaccine in preventing medically-attended influenza virus infection in primary care, Israel, influenza seasons 2014/15 and 2015/16

Eurosurveillance ◽

10.2807/1560-7917.es.2018.23.7.17-00026 ◽

2018 ◽

Vol 23 (7) ◽

Cited By ~ 11

Author(s):

Hamutal Yaron-Yakoby ◽

Hanna Sefty ◽

Rakefet Pando ◽

Rita Dichtiar ◽

Mark A Katz ◽

...

Keyword(s):

Primary Care ◽

Influenza Virus ◽

Influenza Vaccine ◽

Influenza A ◽

Influenza Season ◽

Influenza Virus Infection ◽

Influenza Viruses ◽

Influenza B ◽

Negative Case ◽

Influenza A H1n1

Introduction Influenza vaccine is recommended for the entire population in Israel. We assessed influenza vaccine effectiveness (VE) for the 2014/15 and 2015/16 seasons in Israel, for the first time. Methods: Combined nose and throat swab specimens were collected from patients with influenza-like illness (ILI) presenting to sentinel primary care clinics and tested for influenza virus by RT-PCR. VE of the trivalent inactivated vaccine (TIV) was assessed using test-negative case–control design. Results: During the 2014/15 season 1,142 samples were collected; 327 (28.6%) were positive for influenza, 83.8% A(H3N2), 5.8% A(H1N1)pdm09, 9.2% B and 1.2% A un-subtyped. Adjusted VE against all influenza viruses for this influenza season was −4.8% (95% confidence interval (CI): −54.8 to 29.0) and against influenza A(H3N2), it was −15.8% (95% CI: −72.8 to 22.4). For the 2015/16 season, 1,919 samples were collected; 853 (44.4%) were positive for influenza, 43.5% A(H1N1)pdm09, 57% B, 0.7% A(H3N2) and 11 samples positive for both A(H1N1)pdm09 and B. Adjusted VE against all influenza viruses for this influenza season was 8.8% (95% CI: −25.1 to 33.5), against influenza A(H1N1)pdm09, it was 32.3% (95% CI: (−4.3 to 56.1) and against influenza B, it was −2.2% (95% CI: (−47.0 to 29.0). Conclusions: Using samples from patients with ILI visiting sentinel clinics in Israel, we demonstrated the feasibility of influenza VE estimation in Israel.

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Influenza Vaccine Effectiveness and Waning Effect in Hospitalized Older Adults. Valencia Region, Spain, 2018/2019 Season

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18031129 ◽

2021 ◽

Vol 18 (3) ◽

pp. 1129

Author(s):

Ainara Mira-Iglesias ◽

F. Xavier López-Labrador ◽

Javier García-Rubio ◽

Beatriz Mengual-Chuliá ◽

Miguel Tortajada-Girbés ◽

...

Keyword(s):

Older Adults ◽

Influenza Vaccine ◽

Influenza A ◽

Vaccine Effectiveness ◽

Surveillance Network ◽

Adjuvanted Vaccine ◽

Clinical Registries ◽

Populations At Risk ◽

Influenza A H1n1 ◽

Hospitalized Older Adults

Influenza vaccination is annually recommended for specific populations at risk, such as older adults. We estimated the 2018/2019 influenza vaccine effectiveness (IVE) overall, by influenza subtype, type of vaccine, and by time elapsed since vaccination among subjects 65 years old or over in a multicenter prospective study in the Valencia Hospital Surveillance Network for the Study of Influenza and other Respiratory Viruses (VAHNSI, Spain). Information about potential confounders was obtained from clinical registries and/or by interviewing patients and vaccination details were only ascertained by registries. A test-negative design was performed in order to estimate IVE. As a result, IVE was estimated at 46% (95% confidence interval (CI): (16%, 66%)), 41% (95% CI: (−34%, 74%)), and 45% (95% CI: (7%, 67%)) against overall influenza, A(H1N1)pdm09 and A(H3N2), respectively. An intra-seasonal not relevant waning effect was detected. The IVE for the adjuvanted vaccine in ≥75 years old was 45% (2%, 69%) and for the non-adjuvanted vaccine in 65–74 years old was 59% (−16%, 86%). Thus, our data revealed moderate vaccine effectiveness against influenza A(H3N2) and not significant against A(H1N1)pdm09. Significant protection was conferred by the adjuvanted vaccine to patients ≥75 years old. Moreover, an intra-seasonal not relevant waning effect was detected, and a not significant IVE decreasing trend was observed over time.

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Effectiveness of seasonal influenza vaccine for adults and children in preventing laboratory-confirmed influenza in primary care in the United Kingdom: 2015/16 end-of-season results

Eurosurveillance ◽

10.2807/1560-7917.es.2016.21.38.30348 ◽

2016 ◽

Vol 21 (38) ◽

Cited By ~ 56

Author(s):

Richard Pebody ◽

Fiona Warburton ◽

Joanna Ellis ◽

Nick Andrews ◽

Alison Potts ◽

...

Keyword(s):

Primary Care ◽

United Kingdom ◽

Influenza Vaccine ◽

Influenza A ◽

Immunisation Programme ◽

Influenza B ◽

Live Attenuated Influenza Vaccine ◽

The United Kingdom ◽

Influenza A H1n1 ◽

The Uk

The United Kingdom (UK) is in the third season of introducing universal paediatric influenza vaccination with a quadrivalent live attenuated influenza vaccine (LAIV). The 2015/16 season in the UK was initially dominated by influenza A(H1N1)pdm09 and then influenza of B/Victoria lineage, not contained in that season’s adult trivalent inactivated influenza vaccine (IIV). Overall adjusted end-of-season vaccine effectiveness (VE) was 52.4% (95% confidence interval (CI): 41.0–61.6) against influenza-confirmed primary care consultation, 54.5% (95% CI: 41.6–64.5) against influenza A(H1N1)pdm09 and 54.2% (95% CI: 33.1–68.6) against influenza B. In 2–17 year-olds, adjusted VE for LAIV was 57.6% (95% CI: 25.1 to 76.0) against any influenza, 81.4% (95% CI: 39.6–94.3) against influenza B and 41.5% (95% CI: −8.5 to 68.5) against influenza A(H1N1)pdm09. These estimates demonstrate moderate to good levels of protection, particularly against influenza B in children, but relatively less against influenza A(H1N1)pdm09. Despite lineage mismatch in the trivalent IIV, adults younger than 65 years were still protected against influenza B. These results provide reassurance for the UK to continue its influenza immunisation programme planned for 2016/17.

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The impact of the 2009 influenza A(H1N1) pandemic on attitudes of healthcare workers toward seasonal influenza vaccination 2010/11

Eurosurveillance ◽

10.2807/ese.16.17.19854-en ◽

2011 ◽

Vol 16 (17) ◽

Author(s):

C Brandt ◽

H F Rabenau ◽

S Bornmann ◽

R Gottschalk ◽

S Wicker

Keyword(s):

Medical Students ◽

Influenza Vaccine ◽

Influenza Vaccination ◽

Healthcare Workers ◽

Influenza A ◽

Influenza Season ◽

University Hospital ◽

The Public ◽

Influenza A H1n1 ◽

The Impact

The emergence of the influenza A(H1N1)2009 virus provided a major challenge to health services around the world. However, vaccination rates for the public and for healthcare workers (HCWs) have remained low. We performed a study to review the reasons put forward by HCWs to refuse immunisation with the pandemic vaccine in 2009/10 and characterise attitudes in the influenza season 2010/11 due to the emergence of influenza A(H1N1)2009. A survey among HCWs and medical students in the clinical phase of their studies was conducted, using an anonymous questionnaire, at a German university hospital during an influenza vaccination campaign. 1,366 of 3,900 HCWs (35.0%) were vaccinated in the 2010/11 influenza season. Of the vaccinated HCWs, 1,323 (96.9%) completed the questionnaire in addition to 322 vaccinated medical students. Of the 1,645 vaccinees who completed the questionnaire, 712 had not been vaccinated against the influenza A(H1N1)2009 virus in the 2009/10 season. The main reason put forward was the objection to the AS03 adjuvants (239/712, 33.6%). Of the HCWs and students surveyed, 270 of 1,645 (16.4%) stated that the pandemic had influenced their attitude towards vaccination in general. Many German HCWs remained unconvinced of the safety of the pandemic (adjuvanted) influenza vaccine. For this reason, effective risk communication should focus on educating the public and HCWs about influenza vaccine safety and the benefits of vaccination.

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Vaccine effectiveness for influenza in the elderly in welfare nursing homes during an influenza A (H3N2) epidemic

Epidemiology and Infection ◽

10.1017/s0950268899004410 ◽

2000 ◽

Vol 125 (2) ◽

pp. 393-397 ◽

Cited By ~ 10

Author(s):

Y. DEGUCHI ◽

Y. TAKASUGI ◽

K. NISHIMURA

Keyword(s):

Nursing Homes ◽

Influenza Vaccine ◽

Influenza A ◽

Hospital Admissions ◽

Influenza Virus Infection ◽

Severe Infection ◽

The Elderly ◽

Trivalent Influenza Vaccine ◽

Homes For The Elderly ◽

Vaccine Effect

Influenza vaccine effect on the occurrence and severity of influenza virus infection in a population residing in nursing homes for the elderly was studied as a cohort study during an influenza A (H3N2) epidemic in Japan. Of 22462 individuals living in 301 welfare nursing homes, 10739 voluntarily received inactivated, sub-unit trivalent influenza vaccine in a programme supported by the Osaka Prefectural Government. There were statistically significantly fewer cases of influenza, hospital admissions due to severe infection, and deaths due to influenza in the vaccinated cohort compared to the unvaccinated controls. No serious adverse reactions to vaccination were recorded. Thus influenza vaccination is effective for preventing influenza disease in persons aged 65 years and over, and should be an integral part of the care of this population residing in nursing homes.

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Vaccination Schedules

Tutorial Topics in Infection for the Combined Infection Training Programme ◽

10.1093/oso/9780198801740.003.0062 ◽

2019 ◽

Author(s):

Gee Yen Shin

Keyword(s):

Hepatitis B ◽

Influenza Vaccine ◽

Influenza A ◽

Online Version ◽

Influenza B ◽

Immunisation Schedule ◽

Influenza A H1n1 ◽

Green Book ◽

H3n2 Influenza ◽

The Uk

The vaccines included in the current UK Immunisation Schedule offer protection against the following pathogens: A. Viruses ● Measles ● Mumps ● Rubella ● Polio ● Human Papilloma Virus (certain serotypes) ● Rotavirus ● Influenza virus (flu A and B) ● Varicella zoster virus (shingles) ● Hepatitis B virus B. Bacteria ● Corynebacterium diphtheriae (Diphtheria) ● Clostridium tetani (Tetanus) ● Bordetella pertussis (Pertussis) ● Haemophilus influenzae type B (Hib) ● Neisseria meningitidis (Meningococcal disease—certain serotypes) ● Streptococcus pneumoniae (Pneumococcal disease—certain serotypes) The UK Immunisation Schedule has evolved over several decades and reflects changes in vaccine development and commercial availability, national and sometimes international disease epidemiology, and the latest expert opinion. It is designed to offer optimal protection against infectious diseases of childhood to infants and children at the most appropriate age. The most up-to-date information about the UK Immunisation Schedule is available on the online version of the Department of Health publication commonly known as the ‘Green Book’: Immunisation Against Infectious Disease Handbook (see Further reading. Various chapters of the online version are updated at regular intervals; thus, it is very important to refer to the online version of the Green Book on the website for current guidance. Changes to the UK Immunisation Schedule are made on the recommendation of the independent Joint Committee on Vaccines and Immunisation (JCVI). Several of the UK Immunisation Schedule vaccines are combined vaccines: ● Measles, mumps, and rubella (MMR). ● Hexavalent diphtheria, tetanus, acellular pertussis, inactivated polio virus, Haemophilus influenza type b, hepatitis B (DTaP/IPV/Hib/HepB). ● Diphtheria, tetanus, acellular pertussis, inactivated polio, and Haemophilus influenzae (DTaP/IPV/Hib). ● Diphtheria, tetanus, acellular pertussis, inactivated polio (DTaP/IPV). ● Tetanus, diphtheria, and inactivated polio (Td/IPV). ● Inactivated influenza vaccine: influenza A H1N1, H3N2, influenza B. ● Live attenuated intranasal influenza vaccine: influenza A H1N1, H3N2, influenza B. In the UK, vaccines against single pathogens covered by the MMR vaccine are not recommended and not available in the National Health Service (NHS). There has been some limited demand for single-target vaccines, e.g. measles, due to misguided and unfounded concerns about the alleged risks of autism following MMR.

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