Reduced BNT162b2 mRNA vaccine response in SARS-CoV-2-naive nursing home residents.

Canaday DH, Carias L, Oyebanji OA, Keresztesy D, Wilk D, Payne M, Aung H, St Denis K, Lam EC, Wilson B, Rowley CF, Berry SD, Cameron CM, Cameron MJ, Balazs AB, Gravenstein S, King CL. Reduced BNT162b2 mRNA vaccine response in SARS-CoV-2-naive nursing home residents. medRxiv : the preprint server for health sciences [Preprint]. 2021 Mar 22. Update In: Clin Infect Dis. 2021 May 16;: PMID: 33993265

The SARS-CoV-2 pandemic impact on nursing home (NH) residents prompted their prioritization for early vaccination. To fill the data gap for vaccine immunogenicity in NH residents, we examined antibody levels after BNT162b2 mRNA vaccine to spike, receptor binding domain (RBD) and for virus neutralization in 149 NH residents and 111 health care worker controls. SARS-CoV-2-naive NH residents mount antibody responses with nearly 4-fold lower median neutralization titers and half the anti-spike level compared to SARS-CoV-2-naive healthcare workers. By contrast, SARS-CoV-2-recovered vaccinated NH residents had neutralization, anti-spike and anti-RBD titers similar to SARS-CoV-2-recovered vaccinated healthcare workers. NH residents' blunted antibody responses have important implications regarding the quality and durability of protection afforded by neoantigen vaccines. We urgently need better longitudinal evidence on vaccine effectiveness specific to NH resident populations to inform best practices for NH infection control measures, outbreak prevention and potential indication for a vaccine boost.