Scientific Evidence Doesn’t Back Booster Covid Shots, Researchers Warn — Even For The Delta Variant

The push to roll out Covid-19 booster shots is not being driven by sound scientific evidence, according to a group of international researchers writing in the the Lancet medical journal Monday, who said available evidence shows vaccines to be highly effective against the delta coronavirus variant and that unwarranted messaging about booster doses undermines overall confidence in vaccines. 

Though vaccines are somewhat less effective at preventing symptomatic disease caused by the delta coronavirus variant, studies consistently demonstrate strong protection against severe and symptomatic illness, the researchers said.

With this in mind, the available evidence does not support boosters for the general population, the researchers said, adding that touted indicators of waning immunity (such as falling antibody levels) do not necessarily point to the vaccine becoming less effective over time.