Loading Curie Briefs...
Getting the latest healthcare news for you
Getting the latest healthcare news for you
A better flu shot for nursing homes? A large cluster-randomized trial found that recombinant quadrivalent influenza vaccine (RIV4) reduced laboratory-confirmed flu outbreaks by 18% compared to standard egg-based vaccines during the 2019–2020 season. The benefit wasn't seen in 2020–2021, when flu circulation was near-zero due to COVID-era precautions — making that season difficult to draw conclusions from.
A better flu shot for nursing homes? A large cluster-randomized trial found that nursing homes using recombinant quadrivalent influenza vaccine (RIV4) saw 18% fewer laboratory-confirmed flu outbreaks compared to facilities using standard-dose egg-based inactivated vaccine (IIV4) during the 2019–2020 flu season. Suspected outbreaks were also reduced by a similar margin. The trial enrolled nearly 1,000 Medicare-certified nursing homes across two flu seasons.
The benefit didn't hold in 2020–2021 — but that's largely because flu was nearly absent that year due to COVID-era infection control measures, making it statistically impossible to detect a meaningful difference. Notably, COVID outbreak rates didn't differ between vaccine groups in either season.
By the Numbers:
Why it matters: Nursing home residents are among the most vulnerable to severe flu complications. This trial suggests that upgrading to a higher-antigen recombinant vaccine could meaningfully reduce facility-wide outbreaks — not just individual illness — in typical flu seasons, offering a practical, scalable tool for protecting long-term care populations.
