Coadministration of the BNT162b2 BA.4/5 bivalent mRNA COVID-19 vaccine (BNT162b2-biv) and seasonal influenza vaccine (SIV) in the community setting produced similar effectiveness and outcomes as when the vaccines were given alone, researchers report. “Including this information during autumn or winter vaccination campaigns may improve uptake for both of these underused and potentially life-saving public health interventions,” the authors conclude.
U.S. adults enrolled in commercial health insurance or Medicare Advantage plans and vaccinated with BNT162b2-biv only, SIV only (participants aged 65 years or older received enhanced SIVs), or both on the same day between August 31, 2022, and January 30, 2023, were included in the retrospective comparative effectiveness study. The main outcome measures were COVID-19–related and influenza-related hospitalization, emergency department (ED) or urgent care (UC) encounters, and outpatient visits.
“Overall, 3,442,996 individuals (57.0% female; mean [SD] age, 65 [16.7] years) were included,” the authors write. “A total of 627,735 individuals had BNT162b2-biv and SIV vaccine coadministered, 369,423 had BNT162b2-biv alone, and 2,445,838 had SIV alone. Among those aged 65 years or older (n = 2,210,493; mean [SD] age, 75 [6.7] years; 57.9% female), the coadministration group had a similar incidence of COVID-19–related hospitalization (adjusted hazard ratio [AHR], 1.04; 95% CI, 0.87-1.24) and slightly higher incidence of emergency department or urgent care encounters (AHR, 1.12; 95% CI, 1.02-1.23) and outpatient visits (AHR, 1.06; 95% CI, 1.01-1.11) compared with the BNT162b2-biv–only group. Among individuals aged 18 to 64 years (n = 1,232,503; mean [SD] age, 47 [13.1] years; 55.4% female), the incidence of COVID-19–related outcomes was slightly higher among those who received both vaccines vs BNT162b2-biv alone (AHR point estimate range, 1.14-1.57); however, fewer events overall in this age group resulted in wider CIs. Overall, compared with those who received SIV alone, the coadministration group had a slightly lower incidence of most influenza-related end points (AHR point estimates 0.83-0.93 for those aged ≥65 years vs 0.76-1.08 for those aged 18-64 years). Negative control outcomes suggested residual bias and calibration of COVID-19–related and influenza-related outcomes with negative controls moved all estimates closer to the null, with most CIs crossing 1.00.”