Pfizer/BioNTech Vaccine Less Effective Against South African Coronavirus Strain

The Pfizer/BioNTech vaccine may not protect against a key mutation found on the coronavirus variant identified in South Africa, B.1.351, new UK research suggests.

However, the vaccine should be effective, although at a reduced level, for the coronavirus variant first identified by UK scientists, B1.1.7, researchers from the University of Cambridge reported.

In a small study in just 26 participants, the researchers collected serum samples from participants aged 29 to 89 years who had received an initial dose of vaccine three weeks earlier. They then tested their blood against a synthetic version of the SARS-CoV-2 virus to determine the level of antibodies needed to neutralize the coronavirus and the two variants.

When they tested the sera against the South Africa variant, they discovered that the vaccine likely wouldn’t be effective because 10 times the number of antibodies in the sera was needed to neutralize that variant strain.

In another significant finding, the sera of seven participants over 80 years old couldn’t neutralize the virus after they received an initial vaccine dose but did do so when they received a second shot. This led to the conclusion that “a significant proportion of people aged over 80 may not be sufficiently protected against new variants of the virus until they have had two doses of the vaccine.” ― Jason Scott