The third scenario, in which the booster dose was with the Pfizer vaccine, showed the highest percentages of effectiveness: 56.8% against symptomatic infections and 85.5% against severe cases.
The findings suggest implications for booster shots. While traditional boosters work well for childhood vaccines by increasing antibody levels, the approach becomes more complex with evolving viruses.
WASHINGTON (AP) — Fall means it’s time for just about everybody to get up to date on their flu and COVID-19 vaccines – and a lot of older adults also need protection against another risky ...