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. 2022 May;16(3):452-461.
doi: 10.1111/irv.12950. Epub 2022 Jan 23.

The burden of influenza among Kenyan pregnant and postpartum women and their infants, 2015-2020

Nancy A Otieno  1 , Bryan O Nyawanda  1 , Meredith McMorrow  2 , Martina Oneko  1 , Daniel Omollo  1 , Shirley Lidechi  1 , Marc-Alain Widdowson  3   4 , Brendan Flannery  2 , Sandra S Chaves  2   5 , Eduardo Azziz-Baumgartner  2 , Gideon O Emukule  4
Affiliations

The burden of influenza among Kenyan pregnant and postpartum women and their infants, 2015-2020

Nancy A Otieno et al. Influenza Other Respir Viruses. 2022 May.

Abstract

Background: In tropical Africa, data about influenza-associated illness burden are needed to assess potential benefits of influenza vaccination among pregnant women. We estimated the incidence of influenza among pregnant women and their infants in Siaya County, Kenya.

Methods: We enrolled women at <31 weeks of gestation and conducted weekly follow-up until 6-month postpartum to identify acute respiratory illnesses (ARIs). We defined ARI among mothers as reported cough, rhinorrhoea or sore throat and among infants as maternal-reported cough, difficulty breathing, rhinorrhoea or clinician diagnosis of respiratory illness. We collected nasal/nasopharyngeal and oropharyngeal swabs from mothers/infants with ARI and tested for influenza A and B using molecular assays. We calculated antenatal incidence of laboratory-confirmed influenza among mothers and postnatal incidence among mothers and infants.

Results: During June 2015 to May 2020, we analysed data from 3,026 pregnant women at a median gestational age of 16 weeks (interquartile range [IQR], 13, 18) and followed 2,550 infants. Incidence of laboratory-confirmed influenza during pregnancy (10.3 episodes per 1,000 person-months [95% confidence interval {CI} 8.6-11.8]) was twofold higher than in the postpartum period (4.0 [95% CI 2.6-5.5]; p < 0.01). Incidence was significantly higher among human immunodeficiency virus (HIV)-infected pregnant women (15.6 [95% CI 11.0-20.6] vs. 9.1 [95% CI 7.5-10.8]; p < 0.01). Incidence among young infants was 4.4 (95% CI 3.0-5.9) and similar among HIV-exposed and HIV-unexposed infants.

Conclusion: Our findings suggest a substantial burden of influenza illnesses during pregnancy, with a higher burden among HIV-infected mothers. Kenyan authorities should consider the value of vaccinating pregnant women, especially if HIV infected.

Keywords: burden; infants; influenza; pregnant women.

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Conflict of interest statement

The authors declare that they have no competing interests. Dr. SS Chaves has since left the Centers for Disease Control and Prevention (CDC) and is currently an employee of Sanofi Pasteur.

Figures

FIGURE 1
FIGURE 1
(A) Flow chart of recruitment and follow‐up of study participants. (B) Distribution of acute respiratory illness (ARI) and influenza by month and year
See this image and copyright information in PMC

References

    1. Hartert TV, Neuzil KM, Shintani AK, et al. Maternal morbidity and perinatal outcomes among pregnant women with respiratory hospitalizations during influenza season. Am J Obstet Gynecol. 2003;189(6):1705‐1712. doi:10.1016/S0002‐9378(03)00857‐3 - PubMed
    1. Takeda S, Hisano M, Komano J, Yamamoto H, Sago H, Yamaguchi K. Influenza vaccination during pregnancy and its usefulness to mothers and their young infants. J Infect Chemother. 2015;21(4):238‐246. doi:10.1016/j.jiac.2015.01.015 - PubMed
    1. Jamieson DJ, Honein MA, Rasmussen SA, et al. H1N1 2009 influenza virus infection during pregnancy in the USA. Lancet. 2009;374(9688):451‐458. doi:10.1016/S0140‐6736(09)61304‐0 - PubMed
    1. Katz MA, Gessner BD, Johnson J, et al. Incidence of influenza virus infection among pregnant women: A systematic review. BMC Pregnancy Childbirth. 2017;17(1):1‐12. doi:10.1186/s12884‐017‐1333‐5 - PMC - PubMed
    1. Fell DB, Azziz‐Baumgartner E, Baker MG, et al. Influenza epidemiology and immunization during pregnancy: Final report of a World Health Organization working group. Vaccine. 2017;35(43):5738‐5750. doi:10.1016/j.vaccine.2017.08.037 - PMC - PubMed

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