King County health officials say they're monitoring rising COVID-19 infections in younger people, as new cases in the Seattle area reach levels last seen during a peak this spring.
Nearly three quarters of new cases are in people under 40 years old, King County's top public health official, Dr. Jeff Duchin, told reporters in a briefing Friday.
Duchin said health officials haven't identified one overwhelming driver of new infections — a "smoking gun," as he put it — such as recent protests against racial injustice. Seattle officials tested more than 4,000 people who said they were at protests, he said, and half of one percent tested positive for COVID-19.
And while bars have been flagged as a particularly risky setting for coronavirus transmission, health officials haven't linked an outbreak to any particular bar, Duchin said.
Instead, he said, the recent rise in cases appears to be a result of the cumulative effects of people getting together more often and being less careful in a variety of settings.
"Some of those may be eating and drinking in restaurants and bars, but a lot of that may be socializing with friends and family outside in too-close contact or, particularly, indoors," Duchin said.
"The increase in cases is due to people doing too much in close proximity to one another," he added. "But there’s lots of different activities people are doing that’s leading to COVID transmission."
Sources of new infection may include birthday and graduation parties, Fourth of July celebrations, people working essential jobs, protests, or simply friends and family getting together indoors, Duchin said.
Younger people are less likely to be hospitalized or die due to COVID-19, though the number of people hospitalized for the disease in King County has recently ticked upward, Duchin said.
"We don’t know if this is going to portend a long-term trend or not," he said of the rise in hospitalizations.
King County saw some of the country's first coronavirus infections, and some of the first deaths and nursing home outbreaks. Infections peaked in late March and early April, then declined through April and May.
But, in early June, new cases started to rebound, and are now approaching the previous peak. The increase coincided with warmer weather and businesses reopening in many parts of the state.
The rebound in the Seattle area mirrors a rise in COVID-19 cases statewide, and in many parts of the United States, particularly in the South and West.
Duchin said the virus is not going away, and it's important people get used to behavioral changes that can limit transmission, such as wearing face coverings in public and limiting close interactions with others. He also said improved ventillation may eventually help reduce transmission indoors.
He said it's important people adapt to precautions now, while transmission is "relatively manageable," because health experts expect "much higher transmission" in the fall and winter.
"It’s just critical that, as a community, we understand the long-term nature of this COVID-19 mess," Duchin said. "None of us asked for this, none of us wanted this, but it’s with us. And we have to deal with it. And if we don’t deal with it, it will deal with us."