CDC says young adults now largest group getting infected
71% increase.
The CDC researchers who produced the report drew on three kinds of data: They tallied confirmed cases of COVID-19 in reports from state health departments, examined data from the National Syndromic Surveillance Program to identify patients who went to hospital emergency rooms with COVID-19 symptoms and analyzed coronavirus test results from 37 states.
The trend toward younger patients was evident in all three data sources, the researchers said.
The increase in COVID-19 cases among people in their 20s was striking. In May, 93,741 Americans between the ages of 20 and 29 were newly diagnosed with the disease. That figure swelled to 149,761 in June, 240,105 in July and 189,366 in August.
Americans in their 30s made up the second-largest group of new COVID-19 cases. Among people ages 30 to 39, 101,917 cases were confirmed in May, 130,415 were identified in June, 183,487 were diagnosed in July and 148,500 were added in August.
Over time, these infections in younger adults appeared to spread to older, more vulnerable adults in certain parts of the
country, the researchers wrote.
In the Southeast, an increase in the test positivity rate for people in their 20s and 30s was followed nine days later by an increase in the positivity rate for people in their 40s and 50s. Six days after that, people ages 60 and up had a higher positivity rate as well.
In the Southwest, an increase in the positivity rate for people under 60 was followed about four days later by an increase in the positivity rate for people ages 60 and up. The same pattern was seen in the southcentral states, though the lag there was seven days.
This sequence of events offers “preliminary evidence that younger adults contributed to community transmission of COVID-19 to older adults,” the researchers wrote. “Similar observations have been reported by the World Health Organization,” they added.
There are several plausible explanations for why this might be the case, the CDCteam wrote. Younger adults are more likely to work in restaurants, stores, child care centers and other places that put them at greater risk of exposure to the coronavirus. At the same time, they may be more cavalier about social gatherings and more lax about the need for physical distancing.