Virus cases on the rise — why?

Deaths, hospital stays decline; experts suggest infections now striking younger people

New COVID-19 cases are rising across California as counties reopen, but the state isn’t seeing a similar spike in hospital visits and deaths from the disease, suggesting its progression may have entered a new phase.

Experts aren’t quite sure what to make of the trend, but one surprising theory is gaining traction: that the people now getting sick are younger, healthier and less likely to suffer severe illness.

Data compiled by the Bay Area News Group from California counties show a steady increase in the seven-day average numbers of new cases: from 952 at the start of April — a couple weeks after the statewide pandemic lockdown began — to a new high of 2,786 on Tuesday.

The trend lines for other figures California’s public health officials closely watch don’t show the same upward march. Hospitalizations have continued to slowly decline since the April 7 peak of 5,792 to just over 4,700 on Tuesday. And the seven-day average of new coronavirus deaths has dropped to 62 from the

April 24 peak of 80.

While the state has dramatically increased its testing for the virus, the numbers don’t explain the spike in new infections, experts say.

“What that would suggest to me is we’re testing and diagnosing and reporting people who are at less risk of developing more severe disease, which would mean younger, and with fewer underlying risk factors,” said Dr. George Rutherford, an epidemiologist at UC San Francisco.

This rise in infections comes as California and states across the country reopen and relax stay-at-home rules that slowed the virus but slammed the brakes on the economy. Overall, coronavirus cases are still increasing in 19 states, while 24 are trending downward and seven states are holding steady. Nationally, more than 1.9 million people have been infected by the virus and more than 112,000 have died, according to data from Johns Hopkins University.

The number of COVID-19 hospitalizations since Memorial Day has gone up in California and at least 11 other states: Alaska, Arkansas, Arizona, Kentucky, Mis

sissippi, Montana, North Carolina, Oregon, South Carolina, Texas and Utah, according to data aggregated by CNN from the Covid Tracking Project from May 25 to June 9. In California, however, confirmed and suspected COVID-19 hospitalizations remain lower than they were earlier in May.

Data from California and around the world have demonstrated since the pandemic began earlier this year that COVID-19 is progressively more dangerous with age. Of California’s more than 4,700 fatalities, 78% were people age 65 and older, and 46% were 80 and older. More than half were linked to outbreaks at nursing and senior care facilities.

But of California’s more than 136,000 confirmed COVID-19 cases, about 83% are people younger than 65.

John Swartzberg, clinical professor emeritus of infectious diseases and vaccinology at UC Berkeley, said the theory that the infected are tending toward younger, healthier workers is “tenable.”

It may be too early to tell whether that will continue with an expected surge in new cases from both reopening that began last month to allow things like table service at restaurants to resume, and from protests over the last week.

Symptom onset can lag exposure to the virus up to two weeks, though typically it takes four to five days. Hospitalization from worsening symptoms can take two weeks, and deaths tend to come after three weeks.

This week, for the first time, state public health officials unveiled a closer look at the reasons why coronavirus cases are rising in some California counties:

Santa Clara County attributed a slight uptick in hospitalizations to increased testing of both residents and people living in neighboring counties who seek treatment here, as well as patient transfers from outside the county.

Los Angeles County, hardest hit in the state, saw a surge in cases because of more widespread

testing focused on skilled nursing facilities. In Sacramento County, the disease is spreading because of family gatherings and outbreaks at food processing plants.

In Imperial County, along the Mexican border, the state attributed a spike in cases to U.S. citizens returning from Mexico and hospital staffing shortages.

Nearby, San Bernardino County blamed gatherings after May holidays, outbreaks at state prisons, county jails, and some skilled nursing facilities and patient transfers from Imperial County. County officials also attribute a spike in cases in late May to Mother’s Day weekend, when some businesses started reopening and families likely gathering for the first time in weeks.

In Kings County, which has moved aggressively to reopen, spikes in cases and hospital stays are being driven by outbreaks at Avenal

State Prison and patients from neighboring Tulare County, which has been hit by nursing home outbreaks.

“We haven’t seen any negative impacts from reopening,” said Kings County Supervisor Doug Verboon. “I think the virus is here. We need to learn to live with it. We need to open the state, get back to work and deal with it as it comes.”

But Swartzberg at UC Berkeley remains concerned that the state is reopening too quickly — “We’re going to pay for that” — though he acknowledged the difficulty of maintaining restrictions.

“My sense is that it’s very easy to allow people to get back to doing things they want and need to do — that is work,” he said. “It’s very hard to stop that momentum once you get the train moving.” Southern California News Group staff writer Sandra Emerson and CNN contributed to this report.