About 1,000 counties in the U.S. have vaccination coverage of less than 30 percent as the highly transmissible delta virus circulates across the country, according to the Centers for Disease Control and Prevention (CDC). 

During Thursday’s White House COVID-19 briefing, CDC Director Rochelle Walensky said those counties with lagging vaccination rates are primarily in the Southeast and Midwest. 

She said the CDC is already seeing increasing rates of disease in some areas. 

“Looking across the country, we have made incredible progress toward ending the pandemic. We continue to see overall low numbers of cases, hospitalizations and deaths,” she said. 

“However, looking state by state and county by county, it is clear that communities where people remain unvaccinated are communities that remain vulnerable,” she said. 

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The delta variant makes up about 25 percent of new cases in the U.S. and is expected to eclipse the dominant alpha strain. Walensky said the variant makes up 50 percent of new cases in some regions. 

“We expect to see increased transmission in these communities unless we can vaccinate more people,” she said. 

The U.S. is averaging more than 12,000 new cases per day, a 10 percent increase from the previous week. 

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