Hybrid immunity to SARS-CoV-2 during pregnancy provides more durable infant antibody responses compared to natural infection alone

Sylvia M LaCourse; Erica A Wetzler; Morgan C Aurelio; Jaclyn N Escudero; Stacy S Selke; Alexander L Greninger; Erin A Goecker; Sarina R Barnes; Isabel S Arnould; Ailyn C Pérez-Osorio; Barbra A Richardson; Alisa Kachikis; Janet A Englund; Alison L Drake

doi:10.1093/infdis/jiad592

Hybrid immunity to SARS-CoV-2 during pregnancy provides more durable infant antibody responses compared to natural infection alone

J Infect Dis. 2023 Dec 21:jiad592. doi: 10.1093/infdis/jiad592. Online ahead of print.

Authors

Sylvia M LaCourse^{1

2

3}, Erica A Wetzler², Morgan C Aurelio², Jaclyn N Escudero², Stacy S Selke⁴, Alexander L Greninger⁴, Erin A Goecker⁴, Sarina R Barnes⁴, Isabel S Arnould⁴, Ailyn C Pérez-Osorio⁴, Barbra A Richardson^{2

5}, Alisa Kachikis⁶, Janet A Englund^{7

8}, Alison L Drake^{2

3}

Affiliations

¹ Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA.
² Department of Global Health, University of Washington, Seattle, WA, USA.
³ Department of Epidemiology, University of Washington, Seattle, WA, USA.
⁴ Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA.
⁵ Department of Biostatistics, University of Washington, Seattle, WA, USA.
⁶ Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA.
⁷ Department of Pediatrics, University of Washington, Seattle, WA, USA.
⁸ Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, USA.

PMID: 38128542
DOI: 10.1093/infdis/jiad592

Abstract

Background: Hybrid immunity (infection plus vaccination) may increase maternally-derived SARS-CoV-2 antibody responses and durability vs. infection alone.

Methods: Prospective cohort of pregnant participants with prior SARS-CoV-2 infection (anti-nucleocapsid IgG+, RT-PCR + or antigen+) and their infants had blood collected in pregnancy, delivery/birth, and postpartum tested for anti-spike (anti-S) IgG and neutralizing antibodies (neutAb).

Results: Among 107 participants at enrollment, 40% were unvaccinated and 60% were vaccinated (received ≥1 dose); 102 had previous SARS-CoV-2 infection in pregnancy (median 19 weeks gestation); 5 were diagnosed just prior to prior to pregnancy (median 8 weeks). At delivery, fewer unvaccinated participants (87% anti-S IgG+, 86% neutAb) and their infants (86% anti-S IgG+, 75% neutAb) had anti-S IgG + or neutAb compared to vaccinated participants and their infants (100%, p ≤ 0.01 for all). By 3-6 months postpartum, 50% of infants of unvaccinated participants were anti-S IgG + and 14% had neutAb, vs. 100% among infants of vaccinated participants (all p < 0.01), with lower median antibody responses (anti-S IgG log10 1.95 vs. 3.84 AU/ml, p < 0.01; neutAb log10 1:1.34 vs. 1:3.20, p = 0.11).

Conclusions: In pregnant people with prior SARS-CoV-2, vaccination before delivery provided more durable maternally-derived antibody responses than infection alone in infants through 6 months.

Keywords: SARS-CoV-2; antibody; hybrid immunity; immunization; natural infection; pregnancy; transplacental transfer.

Grants and funding

K23 AI153390/AI/NIAID NIH HHS/United States