SANTA ANA (CNS) — Orange County reported another 522 COVID-19 infections Thursday, while the number of people hospitalized with the virus continued a steady climb.

According to the Orange County Health Care Agency, there were 236 people hospitalized in the county due to the virus, including 56 people in intensive care. That's up from 215 hospitalizations on Tuesday, while the number of ICU patients remained unchanged.

The county reported one more COVID-19 death on Thursday, raising the county's overall death toll to 5,141.

The 522 new cases gave the county a cumulative total from throughout the pandemic of 263,578.

County health officials on Thursday urged residents to adhere to state and federal recommendations on mask wearing. Both the California Department of Public Health and the U.S. Centers for Disease Control and Prevention this week updated their mask guidance, recommending — but not requiring — people to wear masks in indoor public settings, regardless of vaccination status.

Los Angeles County this month issued a health order requiring everyone to wear masks in indoor public settings regardless of vaccination status. No other Southern California counties have taken that step, opting instead to merely recommend mask wearing indoors for vaccinated people. State rules require unvaccinated people to wear masks indoors, but enforcement is largely on the honor system. 

In a statement Thursday, the OC Health Agency "strongly" encouraged residents to "avoid large crowds, where it is easy for the virus to pass from person to person."

The agency noted that between July 21 and Tuesday, the seven-day average rate of people becoming infected with the virus rose from 6.5 per 100,000 residents to 8.6 per 100,000, and the average number of daily COVID cases jumped from 210 to 279. The rate of people testing positive rose from 3.6% to 5.2%.

Increases have largely been attributed to the highly infectious delta strain of the coronavirus.

The positivity rate is more alarming as it reflects more people being infected rather than an increase in testing, Andrew Noymer, an epidemiologist and UC Irvine professor of population health and disease prevention, told City News Service this week.

"Delta is exploding everywhere," Noymer said. "It's become apparent delta has become a big game changer."

Noymer said he expects fewer deaths during this surge because of high vaccination rates among seniors.

The delta variant is a great deal more contagious and produces higher viral loads, but it is not clear how much more deadly it could be, Noymer said.

"It's not clear to me that delta is more deadly, but it is clear to me it's more spreadable," Noymer said.

The rising level of breakthrough infections are concerning, Noymer said. The vaccines are effective at keeping most recipients from hospitalization or serious illness, but Noymer pointed out he is acquainted with two fully vaccinated people who were hospitalized for a COVID-19 infection.

"It's not a crisis, but the direction of travel is backwards and that is the issue," Noymer said. 

The most dominant variants in Orange County in recent weeks have been the delta, alpha and gamma variants, according to the OCHCA. Delta and alpha are considered much more highly contagious, with delta now considered the most dominant strain statewide.

Experts say the current COVID vaccines all provide a high degree of protection against infections and — while they will not prevent all infections — they usually prevent serious illness and death.

As of last Thursday, the county reported that 1,876,853 residents were fully vaccinated. The number of residents who have received Pfizer or Moderna and are fully vaccinated is 1,754,729, and the number of those who received the one-dose Johnson & Johnson vaccine and are fully vaccinated is 122,124.

The county reported there were 214,245 who have received at least one dose of the two-dose Pfizer or Moderna vaccines.