Concurrent administration of COVID-19 and influenza vaccines enhances Spike-specific antibody responses

Abstract

The bivalent COVID-19 mRNA boosters became available in fall 2022 and were recommended alongside the seasonal influenza vaccine. However, the immunogenicity of concurrent versus separate administration of these vaccines remains unclear. Here, we analyzed antibody responses in healthcare workers who received the bivalent COVID-19 booster and the influenza vaccine on the same day or different days. IgG1 responses to SARS-CoV-2 Spike were higher at peak immunogenicity and 6 months following concurrent administration compared with separate administration of the COVID-19 and influenza vaccines. These data suggest that concurrent administration of these vaccines may yield higher and more durable SARS-CoV-2 antibody responses.

Ipsilateral and contralateral coadministration of influenza and COVID-19 vaccines produce similar antibody responses

“…A 2022 systematic review of the safety and immunogenicity of coadministered influenza and COVID-19 vaccines did not identify evidence of immune interference, 3 but this conclusion was based on data from only three studies. 4 , 5 , 6 Subsequent coadministration studies have yielded inconsistent results, but differences between groups were minimal, 7 , 8 , 9 , 10 and most studies compared vaccine coadministration with single vaccine administration rather than sequential vaccination (i.e., with an interval of 1–2 weeks between doses). 5 , 8 , 9 …”