Protection from Coronavirus variants require two face masks.

Delta takes stronger hold: CDC director says delta variant accounts for 83 percent of all COVID-19 cases in US.

The delta variant of the novel coronavirus is now responsible for 83 percent of all sequenced COVID-19 cases in the United States, CDC Director Rochelle Walensky said Tuesday.

That estimate is a major increase from just over two weeks ago. For cases tallied during the week of July 3, the CDC estimated the delta variant accounted for about 50 percent of new infections.

Walensky told the Senate Health Committee that in some parts of the country with low vaccination rates, the percentages are even higher. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, noted that the delta variant could be responsible for up to 90 percent of cases in some areas.

Arkansas, Missouri, Florida and Louisiana are the four states with the highest per capita new cases per day, according to data from the Covid Act Now tracking site.

Vaccination has been uneven across states, and only about half of all eligible people nationwide are fully vaccinated.

Health officials have described the latest stage of the coronavirus as a “pandemic of the unvaccinated” while emphasizing that those who have had their shots are relatively safe.