The C.D.C. says the number of people infected 'far exceeds the number of reported cases' in parts of the U.S.
The number of people infected with the coronavirus in different parts of the United States was anywhere from two to 13 times higher than the reported rates for those regions, according to data released Tuesday by the Centers for Disease Control and Prevention.
The findings suggest that large numbers of people who did not have symptoms or did not seek medical care may have kept the virus circulating in their communities. The study is the largest of its kind to date, although some early data was released last month.
"These data continue to show that the number of people who have been infected with the virus that causes Covid-19 far exceeds the number of reported cases," Dr. Fiona Havers, the C.D.C. researcher who led the study, said in an email. "Many of these people likely had no symptoms or mild illness and may have had no idea that they were infected."
The researchers analyzed samples from people who had routine clinical tests, or were inpatients at hospitals, in 10 cities and states for evidence of prior virus infection. The team released early data for six of the sites in June, and for all 10 locations Tuesday in the journal JAMA. They also released data from later times for eight sites to the C.D.C.'s website on Tuesday.About 40 percent of infected people do not develop symptoms, but they may still pass the virus on to others. The United States now tests roughly 700,000 people a day. The new results highlight the need for much more testing to detect infection levels and contain the viral spread in parts of the country.
For example, in Missouri, the prevalence of infections as of May 30 was 2.8 percent or 171,000, 13 times the reported rate of 12,956 cases, suggesting that the state missed most people with the virus who might have contributed to its outsized outbreak.
In some regions, the gap between estimated infections and reported cases decreased as testing capacity and reporting improved. New York City, for example, showed a 12-fold difference between actual infections and reported cases in early April, but by early May the difference was down to tenfold.
The study indicates that even the hardest-hit area in the study — New York City, where nearly one in four people has been exposed to the virus — is nowhere near achieving herd immunity, the level of exposure at which the spread of the virus would start to dwindle on its own. To reach that level, experts believe at least 60 percent of people in a particular place would have had to be exposed to the virus.
"These figures suggest that the U.S. is nowhere near herd immunity," said Carl Bergstrom, an infectious diseases expert at the University of Washington in Seattle.
New York Times, July 21, 2020
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July 21, 2020
Voices4America Post Script. #PresidentPinocchio lies about how the virus is surging! In the past, he hallucinated that it was disappearing. Now the CDC, which Trump is trying to marginalize, says that the terrible numbers in the USA are even worse. #TrumpVirus #TrumpLiesPeopleDie #BidenBlue202
