By Dr. Max Gomez

NEW YORK (CBSNewYork) – The news about COVID vaccine effectiveness continues to improve, but with some caution.

The coronavirus variant that’s circulating in Brazil is becoming more concerning, both for infectiousness and for severity of disease.

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As CBS2’s Dr. Max Gomez, the good news comes from a CDC report Monday evaluating the effectiveness of the Moderna and Pfizer vaccines in widespread, real world use.

Similar to clinical trial results, both vaccines prevented 90% of infections by two weeks after the second shot. Even one dose provided 80% protection.

COVID VACCINE

Just as importantly, the vaccines appeared to provide good protection against the variants that were circulating during the study period from December of last year until two weeks ago, which includes the U.K. and South Africa mutations.

However, what is concerning is how these vaccines will work against the variant first identified in Brazil.

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“It seems that – and I’m using my words carefully here – that it’s more infectious, meaning spread more easily,” said Dr. Thomas Balcezak, chief clinical officer for the Yale New Haven Health system.

Balcezak says the increased infectiousness is just one of the concerns with the Brazil variant.

CORONAVIRUS PANDEMIC

“It seems to have infected people who were already infected with the coronavirus and have had COVID-19 previously. So it may be able to evade immunity. And number three, there’s some beginning data here to suggest that it may be more deadly,” he said.

Gomez spoke recently with the CEO of Moderna, who committed his company to quickly generate a vaccine against any and every clinically significant variant that pops up. They’re already testing a vaccine against the South Africa variant.

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Balcezak and others emphasize that our best defense right now is to get as many people vaccinated as possible because when there’s less virus circulating, there’s less opportunity for the virus to mutate.

Dr. Max Gomez