COVID-19 spreading fastest among those in 20s, 30s

COVID-19 now appears to be spreading the fastest among people in their 20s and 30s, according to the Baker administration’s new weekly dashboard on the disease.

Over a two-week period from July 26 through August 8, people ages 20 to 39 accounted for 41 percent of all COVID-19 cases. During that time frame, the average age of those infected with the coronavirus was 39 – at the top of the 20-39 age group but way below the average age of cases during the entire pandemic, a number that has been hovering just above 50.

The shift in age of those infected is happening at a time when the Baker administration is trying to rein in the spread of COVID-19 by targeting 46 communities considered at high or moderate risk for the disease and the state as a whole at moderate risk with 4 cases per 100,000 people.

The 46 communities were identified using data for the two-week period ending August 8. That data showed the situation worsening; just a day earlier, the state released data for the two-week period ending August 5 indicating only 33 communities were at moderate or high risk, and the state as a whole was in relatively good shape at 3.2 cases per 100,000 people.

Lawrence, a community that jumped from moderate to high-risk between the two reports, on Friday announced a series of measures to address the problem. Mayor Daniel Rivera said three-quarters of the last 100 people infected in Lawrence attended large gatherings or parties, traveled outside the country or beyond nearby low-risk states, or came in contact with someone who attended a party or traveled to high-risk areas.

Starting Friday night, Rivera said, reports of loud music will be treated as “possible spread events” and addressed by law enforcement, including State Police. The mayor said fines of $300 for noise and mask violations will be issued. He said people returning from outside the state will be visited at their homes to make sure they are complying with quarantine measures. And he said food service establishments will be required to shut down at 10 p.m.

If Lawrence is still deemed high-risk in two weeks, officials said, the city is prepared to reverse course on reopening, returning to Phase 2 or 1.

The shift of infections to younger people fits with anecdotal information suggesting younger people are less concerned about contracting the disease. The numbers are fairly stark. Over a two-week period from July 26 through August 8, people ages 20 to 29 accounted for 864 cases of COVID-19, or 22 percent of the 3,912 cases during that period. Close behind was the 30-39 age group, with 727 cases, or 19 percent of the total.

The 0-19 age group accounted for 16 percent of the cases over the two-week period, while the 40-49 and 50-59 age groups accounted for 14 percent each. Combined, the 60-69, 70-79, and 80-plus groups accounted for 16 percent of the cases.

The same general pattern holds true when adjusted for the size of the population in those age groups. The 20-20 age group had 83.5 cases per 100,000 people over the two-week period and the 30-39 group had 80.1 cases. The other age groups had fewer cases per 100,000. The next-highest were the 40-49 group (63.8 cases), 50-59 (54.8 cases), and 80-plus (51.8 cases).

At a press conference on July 24, Baker said his read of the data at that time indicated the under-30 crowd was not spreading COVID-19. “A lot of what’s driving the increase in cases coming out of the South is just an astonishing run-up in positive test rates for the under-30 crowd,” Baker said. “We do not have that.”

Baker said the under-30 crowd in Massachusetts had seen its case count tick upward and its share of new cases increase, but only relative to older age groups that were once sky-high and had now declined. At the time, the under-30 crowd accounted for a fairly consistent percentage of overall cases, usually in the 12-14 percent range. The latest information shows that same age group accounting for 22 percent of the cases.