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Cited by 556Influenza Virus Research StudiesRespiratory viral infections researchVaccine Coverage and Hesitancy

Influenza vaccination of pregnant women and protection of their infants

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Madhi, Shabir A., Cutland, Clare L., Kuwanda, Locadiah, Weinberg, Adriana, Hugo, Andrea, Jones, Stephanie, Adrian, Peter V., van Niekerk, Nadia +8 more·2014·New England Journal of Medicine
DOI 10.1056/nejmoa1401480
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Abstract

BACKGROUND: There are limited data on the efficacy of vaccination against confirmed influenza in pregnant women with and those without human immunodeficiency virus (HIV) infection and protection of their infants. METHODS: We conducted two double-blind, randomized, placebo-controlled trials of trivalent inactivated influenza vaccine (IIV3) in South Africa during 2011 in pregnant women infected with HIV and during 2011 and 2012 in pregnant women who were not infected. The immunogenicity, safety, and efficacy of IIV3 in pregnant women and their infants were evaluated until 24 weeks after birth. Immune responses were measured with a hemagglutination inhibition (HAI) assay, and influenza was diagnosed by means of reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assays of respiratory samples. RESULTS: The study cohorts included 2116 pregnant women who were not infected with HIV and 194 pregnant women who were infected with HIV. At 1 month after vaccination, seroconversion rates and the proportion of participants with HAI titers of 1:40 or more were higher among IIV3 recipients than among placebo recipients in both cohorts. Newborns of IIV3 recipients also had higher HAI titers than newborns of placebo recipients. The attack rate for RT-PCR-confirmed influenza among both HIV-uninfected placebo recipients and their infants was 3.6%. The attack rates among HIV-uninfected IIV3 recipients and their infants were 1.8% and 1.9%, respectively, and the respective vaccine-efficacy rates were 50.4% (95% confidence interval [CI], 14.5 to 71.2) and 48.8% (95% CI, 11.6 to 70.4). Among HIV-infected women, the attack rate for placebo recipients was 17.0% and the rate for IIV3 recipients was 7.0%; the vaccine-efficacy rate for these IIV3 recipients was 57.7% (95% CI, 0.2 to 82.1). CONCLUSIONS: Influenza vaccine was immunogenic in HIV-uninfected and HIV-infected pregnant women and provided partial protection against confirmed influenza in both groups of women and in infants who were not exposed to HIV. (Funded by the Bill and Melinda Gates Foundation and others; ClinicalTrials.gov numbers, NCT01306669 and NCT01306682.).

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  • Maternal vaccination is a highly effective approach to protect infants from infection.

    “Maternal vaccination is a highly effective approach to protect infants from infection.”

    From Factors Affecting the FcRn-Mediated Transplacental Transfer of Antibodies and Implications for Vaccination in Pregnancy (2017) · cites this paper as [16]

    The Conclusions (p. 1) report partial protection against confirmed influenza in infants not exposed to HIV. The Discussion (p. 8) estimates efficacy in those infants at 45.6% (95% CI, 2.4–69.7). This does not support calling maternal vaccination highly effective against infection generally. (LLM, conf=0.90)

    Experimental — accuracy not yet measured

  • In two RCTs, influenza vaccination reduced the incidence of maternal respiratory illness by 36% and 50.4%.

    “two of these RCTs showed that influenza vaccination reduced the incidence of maternal respiratory illness by 36 and 50.4% (15, 16).”

    From Factors Affecting the FcRn-Mediated Transplacental Transfer of Antibodies and Implications for Vaccination in Pregnancy (2017) · cites this paper as [16]

    The Discussion (p. 9) reports a 36% reduction in maternal clinical febrile respiratory illness in the Bangladesh trial. The HIV-Uninfected Cohort results (p. 6) report 50.4% efficacy against confirmed maternal influenza, not respiratory illness generally; the Discussion says this study found no reduction in clinical respiratory illness. (LLM, conf=0.89)

    Experimental — accuracy not yet measured

  • Infants of influenza-vaccinated mothers were 45-63% less likely to have episodes of proven influenza illness in early infancy (4-6 months of age).

    “infants of influenza vaccinated mothers were 45–63% less likely to have episodes of proven influenza illness in early infancy (4–6 months of age).”

    From Factors Affecting the FcRn-Mediated Transplacental Transfer of Antibodies and Implications for Vaccination in Pregnancy (2017) · cites this paper as [16]

  • Maternal vaccination with pertussis, tetanus and influenza vaccines reduces the risk of disease soon after birth and demonstrates the role of antibodies in protection against these diseases.

    “Maternal vaccination with pertussis24, tetanus25 and influenza26 vaccines harnesses this important protective adaptation to reduce the risk of disease soon after birth and clearly demonstrates the role of antibodies in protection against these diseases.”

    From A guide to vaccinology: from basic principles to new developments (2021) · cites this paper as [26]

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Research works printed but not linked: 2

  1. [1]1. Meeting of the Strategic Advisory Group of Experts on Immunization, April 2012 - conclusions and recommendations. Wkly Epidemiol Rec 2012; 87: 20116.
  2. [19]19. Vaccines against influenza WHO position paper - November 2012. Wkly Epidemiol Rec 2012; 87: 461-76.

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Authors
Madhi, S. A., Cutland, C. L., Kuwanda, L., Weinberg, A., Hugo, A., Jones, S., Adrian, P. V., van Niekerk, N., Treurnicht, F., Ortiz, J. R., Venter, M., Violari, A., Neuzil, K. M., Simões, E. A. F., Klugman, K. P., & Nunes, M. C.
Affiliations
  • National Health Laboratory Service (ZA)
  • Respiratory and Meningeal Pathogens Research Unit (ZA)
  • University of Colorado Anschutz (US)
  • University of Washington (US)
  • Colorado School of Public Health (US)
  • Emory University (US)
ORCID
Venue
New England Journal of Medicine
Publisher
Massachusetts Medical Society
Published
2014-09-04
Volume
371
Issue
10
Pages
918-931
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
DOI
10.1056/nejmoa1401480
OpenAlex
W2151524246
Cited by
556
References
34
Citations by year
2026: 16 · 2025: 26 · 2024: 22 · 2023: 35 · 2022: 25 · 2021: 53 · 2020: 59 · 2019: 80 · 2018: 58 · 2017: 66 · 2016: 59 · 2015: 44 · 2014: 9 · 2013: 2
FWCI
44.83
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • UpSpace Institutional Repository (University of Pretoria) (submittedVersion)
Funders
  • Bill and Melinda Gates Foundation (OPP1002747)
  • Pfizer
  • GlaxoSmithKline
  • Sanofi
  • Gilead Sciences
  • National Research Foundation
  • Drugs for Neglected Diseases initiative
  • National Institutes of Health (UL1TR000154, TR000154)
  • Sanofi Pasteur
  • Medical Research Council
  • National Center for Advancing Translational Sciences (TR000154)
  • Colorado Clinical and Translational Sciences Institute (UL1 TR000154, TR000154)
Topics
  • Health Sciences › Medicine › Epidemiology › Influenza Virus Research Studies
  • Health Sciences › Medicine › Epidemiology › Respiratory viral infections research
  • Social Sciences › Health › Vaccine Coverage and Hesitancy
Keywords
influenza vaccination, pregnancy, HIV infection, trivalent inactivated influenza vaccine, infant protection, vaccine efficacy, seroconversion, hemagglutination inhibition, mother-to-child transmission, South Africa, maternal and child health, infant HIV prevention, maternal morbidity, maternal morbidity reduction
MeSH terms
Adult, Double-Blind Method, Female, Humans, Infant, Infant, Newborn, Infant, Premature, Influenza, Human, Influenza Vaccines, Male, Pregnancy, Pregnancy Complications, Infectious, Pregnancy Outcome, South Africa, Vaccines, Inactivated, HIV Infections, Kaplan-Meier Estimate, Young Adult

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