SANTA ANA, Calif. (CNS) — Orange County's COVID-19 hospitalization number climbed again Thursday, while the county also logged a dozen more fatalities.

Hospitalizations increased from 190 Wednesday to 200 Thursday, with the number of intensive care unit patients increasing from 41 to 42, according to the Orange County Health Care Agency. There were 175 hospitalized patients in the county on Monday.

The county had 23.2% of its ICU beds available and 71% of its ventilators as of Thursday.

Hospitalizations began rising the past few days, following a steady downward slide since late last month.

"It's definitely once again showing us it's a seasonal virus," Dr. Jose Mayorga, executive director of the UCI Health Family Health Centers, told City News Service Wednesday. "We're kind of in this lull in between summer right before the late fall and winter season." 

Like other experts, Mayorga said he expects a wave this winter, but it's unknown how significant it will be.

"It won't likely be as bad as last winter's surge, but there's still quite a few folks yet to be vaccinated, and our children under 12 don't have that option," Mayorga said.

Andrew Noymer, an epidemiologist and UC Irvine professor of population health and disease prevention, told City News Service on Wednesday that he was concerned about the rise in hospitalizations.

"I'm not pleased to see hospitalizations at 190 after having been 175," Noymer said. "Whether or not this is a little blip or something larger is too early to tell. The percentage positive is still looking pretty good, so that's good. But people are in the hospital and that's not good. But we're still below 200 and that's good enough for now."

As of Oct. 16, the county's new case rate per 100,000 vaccinated residents was 2.7, down from 3.1 on Oct. 9. The rate among unvaccinated residents dipped from 14.6 per 100,000 to 13.7.

The number of fully vaccinated residents in Orange County increased from 2,147,048 last Thursday to 2,162,820 this week.

That number includes an increase from 2,005,340 to 2,019,902 of residents who have received the two-dose regimen of vaccines from Pfizer or Moderna. The number of residents receiving the one-dose Johnson & Johnson vaccine increased from 141,708 to 142,918.

There are 190,068 residents who have received one dose of the Pfizer or Moderna vaccines.

The top providers of vaccines are the OCHCA at 26.20%, CVS at 18.4%, Walgreens at 6.2%, Kaiser Permanente at 5.4%, UC Irvine Health at 2.7%; Walmart at 1.9%, Safeway, Vons and Pavilions at 1.2%; Families Together of Orange County at 1.10% and multiple others below 1%.

The county's overall weekly COVID case rate per 100,000 residents, which is released on Tuesdays, improved from 7 to 6.6 this week, while the testing-positivity rate fell from 2.7% to 2.5%. The county's Health Equity Quartile positivity rate — which measures progress in low-income communities — dropped from 3% to 2.5%.

The county also reported 396 new infections and logged 12 more deaths Thursday, raising the cumulative totals to 302,631 cases and 5,550 deaths since the pandemic began.

Of the deaths reported Thursday, four occurred this month, raising the death toll for October to 12.

Five occurred in September, hiking the death toll last month to 154. Another two occurred in August, raising the death toll for that month to 172. Another of the fatalities occurred in July.

In contrast, the death toll before the more contagious delta variant-fueled surge was 29 in July, 19 for June, 26 for May, 46 for April, 199 for March, 615 for February, 1,585 for January — the deadliest month of the pandemic — and 976 for December, the next deadliest.

Most of those who died in September were unvaccinated, and the same trend is true for those who are hospitalized, Dr. Regina Chinsio-Kwong, the county's deputy county health officer, said.

Chinsio-Kwong again encouraged residents to get flu and COVID-19 shots, stressing it is safe to get both.

"Flu is around the corner — technically it's already here," she said. "It's between October and May and we'll see a spike in November."

U.S. Centers for Disease Control and Prevention officials are projecting a "more severe flu season compared with last season," because "many people were not exposed to the flu last season or did not get vaccinated. The last thing you want to do is deal with COVID as well as the flu."

Mayorga said it is likely by the end of this week that the CDC will approve the mix-and-match process of administering vaccines, allowing recipients of one company's vaccine to receive a booster from another company's medicine. Studies have shown that the one-shot Johnson & Johnson vaccine's potency is increased by 35 times with a Pfizer vaccine and 76 times by Moderna's vaccine.

What's unique is that the Johnson & Johnson vaccine is based on older technology similar to the flu shot, but the Moderna and Pfizer vaccines utilize the new mRNA technology. What's not new, however, is the idea of mixing and matching different vaccines, Mayorga said. 

"A great example of that has long been in existence with the flu vaccine," Mayorga said. "The flu vaccine has set that precedence. Every year, no one really questions what flu vaccine they get. You get typically what the doctor's office is offering. Mixing and matching is not something that is not unheard of."

Mayorga said the human immune systems "are very, very intelligent and complex," so the different approaches to combating coronavirus will enhance the ability to fend off infections.

The mixing-and-matching of the COVID-19 vaccines also demonstrates how safe they are, Mayorga added.

But he said it was more important to promote vaccines in general, not just boosters.

"We know the odds are that people who got vaccines are going to go out and get a booster," he said. "But what we really want to see is people who have not gotten a vaccine to get their first series. It is absolutely proven that if you're not vaccinated and you get sick you're 11 times more at risk of dying. Why subject yourself to that?"