Better than booster shots, non-vaccines promise to build Covid immunity

Monoclonal antibodies boost immune response to infections by binding to particular sites on the spike protein of the virus that causes Covid-19.

Vaccines never promised us perfect protection. Yet studies are showing that our defenses are declining faster than expected.

One from Oxford University published last week showed that the efficacy of the BioNTech/Pfizer Inc. vaccine was halved after four months. Another, published Tuesday by the U.S. Centers for Disease Control, reported that since the delta variant became predominant, the efficacy of mRNA vaccines against infection decreased to 66% from 91% among front-line workers.

If Covid vaccines are a leaky roof, how do we plug the gaps? Most of the discussion so far has focused on booster shots as the best way