Longitudinal, population-based cohort study of prenatal influenza vaccination and influenza infection in childhood

Damien Foo, Mohinder Sarna, Gavin Pereira, Hannah C. Moore, Annette K. Regan

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


Background: Influenza vaccination is recommended to protect mothers and their infants from influenza infection. Few studies have evaluated the health impacts of in utero exposure to influenza vaccine among children more than six months of age. Methods: We used probabilistically linked administrative health records to establish a mother–child cohort to evaluate the risk of influenza and acute respiratory infections associated with maternal influenza vaccination. Outcomes were laboratory-confirmed influenza (LCI) and hospitalization for influenza or acute respiratory infection (ARI). Adjusted hazard ratios (aHRs) accounted for child's Aboriginal status and were weighted by the inverse-probability of treatment. Results: 14,396 (11.5%) children were born to vaccinated mothers. Maternally vaccinated infants aged < 6 months had lower risk of LCI (aHR: 0.33; 95% CI: 0.13, 0.85), influenza-associated hospitalization (aHR: 0.39; 95% CI: 0.16, 0.94) and ARI-associated hospitalization (aHR: 0.85; 95% CI: 0.77, 0.94) compared to maternally unvaccinated infants. With the exception of an increased risk of LCI among children aged 6 months to < 2 years old following first trimester vaccination (aHR: 2.28; 95% CI: 1.41, 3.69), there were no other differences in the risk of LCI, influenza-associated hospitalization or ARI-associated hospitalization among children aged > 6 months. Conclusion: Study results show that maternal influenza vaccination is effective in preventing influenza in the first six months and had no impact on respiratory infections after two years of age.

Original languageEnglish
Pages (from-to)656-665
Number of pages10
Issue number4
Publication statusPublished - 28 Jan 2022


Dive into the research topics of 'Longitudinal, population-based cohort study of prenatal influenza vaccination and influenza infection in childhood'. Together they form a unique fingerprint.

Cite this