Governments are locked in a deadly race, rushing to dispense vaccines needed to head off an enemy showing signs that it, too, has picked up the pace. The announcements arrived even as President Biden banned travel to the United States from South Africa, in hopes of stanching the spread of one variant. And Merck, a leading drug company, on Monday abandoned two experimental coronavirus vaccines altogether, saying they did not produce a strong enough immune response against the original version of the virus. The vaccines made by Moderna and Pfizer-BioNTech are both effective against new variants of the coronavirus discovered in Britain and South Africa, the companies reported. But they are slightly less protective against the variant in South Africa, which may be more adept at dodging antibodies in the bloodstream.

Source: New York Times January 25, 2021 13:30 UTC