Effectiveness of Influenza Vaccination of Pregnant Women for Prevention of Maternal and Early Infant Influenza-Associated Hospitalizations in South Africa: A Prospective Test-Negative Study.

Nunes, Marta C; Walaza, Sibongile; Meiring, Susan; Zar, Heather J; Reubenson, Gary; McMorrow, Meredith; Tempia, Stefano; Rossi, Liza; Itzikowitz, Raphaela; Bishop, Kate; Mathunjwa, Azwifarwi; Wise, Amy; Treurnicht, Florette K; Hellferscee, Orienka; Laubscher, Matt; Serafin, Natali; Cutland, Clare L; Madhi, Shabir A; Cohen, Cheryl

Nunes, Marta C; Walaza, Sibongile; Meiring, Susan; Zar, Heather J; Reubenson, Gary; McMorrow, Meredith; Tempia, Stefano; Rossi, Liza; Itzikowitz, Raphaela; Bishop, Kate; Mathunjwa, Azwifarwi; Wise, Amy; Treurnicht, Florette K; Hellferscee, Orienka; Laubscher, Matt; Serafin, Natali; Cutland, Clare L; Madhi, Shabir A; Cohen, Cheryl.

Afiliação

Nunes MC; South African Medical Research Council, Faculty of Health Sciences, Vaccines and Infectious Diseases Analytics Research Unit, University of the Witwatersrand, Johannesburg, South Africa.
Walaza S; Department of Science and Technology/National Research Foundation, Faculty of Health Sciences, South African Research Chair Initiative in Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa.
Meiring S; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
Zar HJ; School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Reubenson G; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
McMorrow M; School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Tempia S; Division of Public Health Surveillance and Response, National Institute for Communicable Diseases, Johannesburg, South Africa.
Rossi L; Department of Paediatrics and Child Health, and South African Medical Research Council Unit on Child and Adolescent Health, University of Cape Town, Cape Town, South Africa.
Itzikowitz R; Department of Paediatrics and Child Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Bishop K; Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Mathunjwa A; School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Wise A; Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Treurnicht FK; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
Hellferscee O; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
Laubscher M; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
Serafin N; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
Cutland CL; Department of Obstetrics and Gynaecology, Rahima Moosa Mother and Child Hospital, University of the Witwatersrand, Johannesburg, South Africa.
Madhi SA; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.
Cohen C; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa.

Open Forum Infect Dis ; 9(11): ofac552, 2022 Nov.

Article em En | MEDLINE | ID: mdl-36447608

ABSTRACT

ABSTRACT

Background:

Influenza vaccination during pregnancy reduces influenza-associated illness in the women and their infants, but effectiveness estimates against influenza-associated hospitalization are limited and lacking from settings with high human immunodeficiency virus (HIV) infection prevalence. We assessed the effect of maternal vaccination in HIV-uninfected women and women with HIV in preventing influenza-associated hospitalizations in infants and the women.

Methods:

During 2015-2018, influenza vaccination campaigns targeting pregnant women were augmented at selected antenatal clinics; these were coupled with prospective hospital-based surveillance for acute respiratory or febrile illness in infants aged <6 months and cardiorespiratory illness among pregnant or postpartum women. Vaccine effectiveness (VE) was assessed using a test-negative case-control study.

Results:

Overall, 71 influenza-positive and 371 influenza-negative infants were included in the analysis; mothers of 26.8% of influenza-positive infants were vaccinated during pregnancy compared with 35.6% of influenza-negative infants, corresponding to an adjusted VE (aVE) of 29.0% (95% confidence interval [CI], -33.6% to 62.3%). When limited to vaccine-matched strains, aVE was 65.2% (95% CI, 11.7%-86.3%). For maternal hospitalizations, 56 influenza-positive and 345 influenza-negative women were included in the analysis, with 28.6% of influenza-positive women being vaccinated compared with 38.3% of influenza-negatives, for an aVE of 46.9% (95% CI, -2.8% to 72.5%). Analysis restricted to HIV-uninfected women resulted in 82.8% (95% CI, 40.7%-95.0%) aVE. No significant aVE (-32.5% [95% CI, -208.7% to 43.1%]) was detected among women with HIV.