New study shows need for full vaccination to protect against delta variant

A study released Thursday found that one dose of the Pfizer-BioNTech or AstraZeneca vaccines “barely” offers any protection against the delta variant of COVID-19.

The peer-reviewed study published by the journal Nature found that only 10 percent of blood samples from people who had received one dose of either vaccine were able to neutralize the delta strain, which is now the dominant form of the coronavirus in the U.S.

That number, however, rose to 95 percent when a second vaccine dose was added.

“A single dose of Pfizer or AstraZeneca was either poorly or not at all efficient against Beta and Delta variants. Both vaccines generated a neutralizing response that efficiently targeted variant Delta only after the second dose,” the researchers wrote.

The French researchers looked at how well antibodies produced by natural infection and vaccines can neutralize the alpha, beta and delta variants, in addition to a variant that is comparable to the original version of the virus, The New York Times reported.

The study examined 103 people who previously had COVID-19, the Times reported. Researchers determined that the delta variant was less sensitive than the alpha samples taken from people who were not vaccinated.

Scientists also looked at blood samples from 59 people after they were inoculated with both doses of the Pfizer-BioNTech or AstraZeneca vaccines.

Concerns regarding the delta variant are rising throughout the world and in the U.S. as the strain, which is believed to be more easily transmissible than other variants, spreads rapidly.