Johnson & Johnson vaccine effective against variants: study

The Johnson & Johnson COVID-19 vaccine produces several immune responses allowing it to be effective against different variants of the virus, according to a study released Wednesday.

The research, published in Nature as an accelerated article preview, determined that the Johnson & Johnson vaccine activated immune responses against the original COVID-19 strain, as well as the Alpha, Beta, Gamma and Epsilon variants. 

The study concluded that the Johnson & Johnson vaccine “offered strong protection against symptomatic” cases of COVID-19 in South Africa and Brazil where variants have caused most sequenced cases.

Researchers studied the antibody and cellular immune responses of 20 volunteers between the ages of 18 and 55. 

The study did find that less neutralizing antibodies appeared when fighting against the Beta and Gamma variants, first found in South Africa and Brazil, respectively, when compared to the original COVID-19 strain. 

Those with the Beta strain produced five-times fewer neutralizing antibodies than those with the original strain. For the Gamma variant, people developed 3.3 times less of these antibodies. 

But the non-neutralizing antibody and T cell immune responses were “largely preserved” and made up for it when combating the variants, which researchers said indicated how these immune responses could protect against COVID-19 and its variants.

The study determined that a single dose of Johnson & Johnson protected against severe COVID-19 in 86 percent of participants in the U.S., 88 percent of those in Brazil and 82 percent in South Africa.

Since the Food and Drug Administration issued an emergency use authorization for the Johnson & Johnson vaccine in February, more than 11.2 million doses of the vaccine have been administered in the U.S.

In April, U.S. health officials briefly recommended a pause in giving out Johnson & Johnson vaccines after rare cases of blood clots emerged. Authorities later determined that the benefits of the shot outweighed the risks and lifted the suggested pause.