A new wave of COVID-19 cases caused by the highly transmissible delta variant is exacerbating
the worldwide public health crisis, and has led to consideration of the potential
need for, and optimal timing of, booster doses for vaccinated populations.1 Although
the idea of further reducing the number of COVID-19 cases by enhancing immunity in
vaccinated people is appealing, any decision to do so should be evidence-based and
consider the benefits and risks for individuals and society. COVID-19 vaccines continue
to be effective against severe disease, including that caused by the delta variant.
the worldwide public health crisis, and has led to consideration of the potential
need for, and optimal timing of, booster doses for vaccinated populations.1 Although
the idea of further reducing the number of COVID-19 cases by enhancing immunity in
vaccinated people is appealing, any decision to do so should be evidence-based and
consider the benefits and risks for individuals and society. COVID-19 vaccines continue
to be effective against severe disease, including that caused by the delta variant.