COVID-19 cases surge to previous numbers

Infections close to reaching high levels area had last summer

Consider this California's first coronavirus surge of the endemic era.

Even with the rise in home tests that don't make it into official statistics, the state is now reporting more confirmed cases per day than it did at the peak of the summer 2020 surge, and it is closing in on summer 2021 surge levels.

But while public health officials and experts are concerned about the increasing transmission levels, they aren't expecting a crush of disease to overwhelm hospitals, as past surges did.

“Most of the people that we're seeing in the hospital are having very mild disease compared to the previous waves,” said Dr. John Mourani, medical director

of infectious disease at Pomona Valley Hospital Medical Center.

A number of factors are at play, experts say. While the variant that’s dominant right now is extremely contagious, it appears to cause less severe disease than previous forms of COVID-19, said Dr. Robert Kim-Farley, a professor at UCLA Fielding School of Public Health, who is an expert in epidemiology and infectious diseases. High rates of immunity from vaccination or past infections also are protecting people who get sick against severe disease and death and medical treatment has improved.

“This is what endemicity looks like,” said Andrew Noymer, a professor of population health and disease prevention at UC Irvine.

There’s no exact dividing line between pandemic and endemic, and while coronavirus may still be referred to as a pandemic because it’s still circulating globally, officials in many places, including California, have shifted from treating it as an emergency to living with it.

An endemic means a virus “is always with us, circulating and from time to time we may have surges, but because it is less deadly, because of vaccinations and natural immunity, the severity does not put as many people in the hospital,” Kim-Farley said.

Even so, he said, the rising case numbers should be a wake-up call for people to get vaccinated or get a booster shot if they aren’t already, and take other reasonable precautions.

“We need to be more vigilant, especially when in crowded settings, to wear a mask to help reduce the rate of transmission,” Kim-Farley said. “Also, masking is important for persons who are at higher risk of the disease, such as those who are elderly, or with multiple medical conditions, or especially the immunosuppressed.”

California reported an average of 11,200 cases per day in the week ending May 17 — the most recent week with reliable data, because the numbers are based on what day a person got tested or got sick, not when their results came back, and results take some time.

That’s double the cases from just three weeks prior and more than five times higher than the recent low of about 2,100 cases per day in the week ending March 21.

Cases have risen in every county in California, but the increases have been sharpest in rural northern and central regions, while the Bay Area currently has the highest case rates when adjusted for population.

San Francisco added 378 confirmed cases for every 100,000 residents from May 11 to May 17, according to the latest state data. Del Norte, Santa Clara, San Mateo, Sonoma and Marin counties all had more than 300cases per 100,000 residents as well.

Rates were lower in Southern California: 206 in SanDiego County, 200 in Los Angeles County, 143 in Orange County, 132 in Riverside County and 105 in San Bernardino County.

Kim-Farley said a big reason why the Bay Area is doing worse now may be that it did much better than Southern California in previous surges, which means there are more people there who are still susceptible.

California as a whole has been doing better than some other parts of the U.S. — much of the Northeast and parts of the upper Midwest have high community levels of COVID-19, according to a Centers for Disease Control and Prevention measurement that’s based on both case and hospitalization rates. California has a handful of counties with medium levels, including L.A. County as of last week, but most of the state is still considered low.

“I think we need to look to the Northeast to recognize that we may be in for further increases here in Southern California, but at the same time I’m hopeful that we do tend to use masks more than in the

Northeast, so that may help blunt the height of the surge,” Kim-Farley said.

He also said California’s higher vaccination levels among seniors and higher booster shot rates.