Malick Kone gets his first dose of the COVID-19 vaccine from Elaina Smith at the Islamic Center of Maine in Orono on April 4, 2021. Credit: Linda Coan O'Kresik / BDN

NEW YORK — New research from France adds to evidence that COVID-19 vaccines offer strong protection against the delta variant that is spreading rapidly around the world and accounts for most U.S. infections.

The delta variant is surging through populations with low vaccination rates. Researchers from France’s Pasteur Institute reported new evidence Thursday in the journal Nature that full vaccination is critical.

In laboratory tests, a single dose of the Pfizer or AstraZeneca vaccines “barely inhibited” the delta variant. But after a second dose, almost all experienced a big boost in immunity.

Dr. Rochelle Walensky, director of the U.S. Centers for Disease Control and Prevention, says highly immunized swaths of America are getting back to normal while hospitalizations are rising in other places.

A few weeks ago, the delta variant accounted for just over a quarter of new U.S. cases. But it now accounts for just over 50 percent, and in some places, such as parts of the Midwest, as much as 80 percent.