CDC: More than 90% of US counties have ‘substantial or high’ COVID-19 transmission

The U.S. Centers for Disease Control and Prevention revealed Thursday that more than 90% of counties in the country are experiencing "substantial or high" rates of transmission of the COVID-19 virus. 

During a White House COVID-19 press briefing, Dr. Rochelle Walensky, director of the CDC, said that cases, hospitalizations and deaths have all increased over the past week. 

"Yesterday, CDC recorded 132,384 new cases of COVID-19. Our seven-day average is about 113,000 cases per day and this represents an increase of nearly 24% from the prior seven-day average. The seven-day average of hospital admissions is at about 9,700 per day, an increase of about 31% from the prior seven-day period. And the seven-day average of daily deaths has also increased to 452 per day. An increase of 22% from the prior seven-day period. We continue to see cases, hospitalizations and deaths increase across the country," Walensky said. 

Walensky also said the CDC is ramping up its efforts to vaccinate more vulnerable populations, including pregnant people. 

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"We now have new data that reaffirms safety of our vaccines for people who are pregnant including those early in pregnancy and around the time of conception. These data build on previous evidence from three safety monitoring systems that did not find any safety concerns for pregnant people who are vaccinated late in pregnancy or for their babies. Now, these new data found no increase in the risk for miscarriage among people who received an mRNA COVID-19 vaccine before 20 weeks of pregnancy," Walensky said. 

She also noted that the surge in delta variant cases "make vaccination for this population more urgent than ever." 

Expectant women run a higher risk of severe illness and pregnancy complications from the coronavirus, including perhaps miscarriages and stillbirths. But their vaccination rates are low, with only about 23% having received at least one dose, according to CDC data. 

The updated guidance released on Wednesday comes after a CDC analysis of new safety data on 2,500 women showed no increased risks of miscarriage for those who received at least one dose of the Pfizer or Moderna vaccine before 20 weeks of pregnancy. The analysis found a miscarriage rate of around 13%, within the normal range. 

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The CDC’s advice echoes recent recommendations from top obstetrician groups. The agency had previously encouraged pregnant women to consider vaccination but had stopped short of a full recommendation. The new advice also applies to nursing mothers and women planning to get pregnant. 

Although pregnant women were not included in studies that led to authorization of COVID-19 vaccines, experts say real-world experience in tens of thousands of women shows that the shots are safe for them and that when given during pregnancy may offer some protection to newborns. 

Walensky also noted on Thursday that the CDC and the U.S. Food and Drug Administration would be holding a meeting of their advisory committees to discuss booster shots for people with compromised immune systems, which makes up less than 3% of the U.S. population. 

"We’ve been working to identify how best to provide increased protection to these vulnerable people who are disproportionately impacted by severe outcomes due to COVID-19. FDA is working with Pfizer and Moderna to allow boosters for these vulnerable people. An additional dose to help increase protection for these individuals, which is especially important as the delta variant spreads," Walensky added. 

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The U.S. is seeing the virus storming back, driven by a combination of the highly contagious delta variant and lagging vaccination rates, especially in the South and other rural and conservative parts of the country. 

New cases nationwide are averaging about 123,000 per day, a level last seen in early February, and deaths are running at over 500 a day, turning the clock back to May. 

Walensky continued to encourage those who are unvaccinated to get their shots, saying that the most vulnerable people during the pandemic are those who have yet to get their COVID-19 vaccines. 

"We know that our vaccines are safe and effective, and if you have not gotten the vaccine yet, please do so today," she concluded. 

The Associated Press contributed to this report.