Unlike L.A., San Diego will not recommend indoor masking for vaccinated

Saying that it continues to monitor Delta coronavirus variant cases, San Diego County signaled Tuesday that it will not follow the lead of its neighbor to the north and push for indoor mask wearing.

On Monday, Los Angeles County public health officials said they were urging that residents — even those who are fully vaccinated — mask up indoors as Delta variant cases increase.

While Dr. Wilma Wooten, San Diego County’s public health officer, was silent when asked through county communications channels whether she would follow suit, Nathan Fletcher, chair of the county Board of Supervisors, made his own announcement Tuesday, indicating that the region “will continue to align our public health guidance with CDC (U.S. Centers for Disease Control and Prevention) and CDPH (California Department of Public Health) and do not anticipate any changes.”

Federal and state health agencies recommend indoor mask wearing only for the unvaccinated. Those who are two weeks beyond their second dose — or who received a single dose of the Johnson & Johnson vaccine — are counseled that it is safe to congregate indoors sans masks.

Fletcher noted in his statement that Delta variants remain the biggest risk for those who have not yet been immunized.

“Almost 95 percent of our Delta variant cases are from those not fully vaccinated,” Fletcher said.

The announcement came on the same day that Scripps Health shut down its mass vaccination site at the Del Mar Fairgrounds. A lack of demand for vaccines closed similar sites this month, shifting vaccine seekers to doctors offices and county vaccination clinics.

Though still new enough that it is not completely understood, studies are showing that the variant is more transmissible than other variants and is likely less susceptible to monoclonal antibody treatments that provide a significant option for those who experience symptoms after infection.

A June 23 coronavirus presentation from the CDC indicates that two doses of mRNA vaccine appear to offer significant protection against the Delta variant. Two studies out of Scotland, the CDC notes, showed that two doses of the Pfizer vaccine offered 79 percent effectiveness against Delta versus 92 percent against B.1.1.7, the variant first spotted in the United Kingdom. Two doses appeared to also offer similar protection against hospitalization.

Dr. Robert “Chip” Schooley, an infectious diseases expert at the University of California San Diego, said in an email Tuesday that while San Diego County may not be calling for wearing masks indoors, some should do so anyway.

“If you are at increased risk for COVID because of age, an underlying condition or being immunocompromised, it would be prudent to put the mask back on in indoor public places and to ask those who live with you do do the same,” Schooley said. “I would recommend this particularly strongly to people in those categories who got the J&J vaccine.

“We’ll have to continue to watch closely and see where things are headed here in our county.”

Kristian Andersen, an immunologist and molecular biologist at Scripps Research whose lab is on the forefront of the global effort to sequence and analyze the genetics of novel coronavirus, called the Los Angeles masking guidance prudent, adding that he personally will continue to do so though he is fully vaccinated.

“That said, with our current number (of cases) I think we’re in a good place as mandates are likely to be ineffective at the moment so it’s more of a personal choice,” Andersen said.

While not yet dominant in San Diego, the delta variant will inevitably become dominant in San Diego, and when it does, those who are not fully vaccinated will be at the greatest risk by far.

“We know that being fully vaccinated is by far the most effective way to combat this and other variants,” Andersen said. “We have to realize that we’re all highly likely to get exposed to SARS-CoV-2 in the future, so the choice we have to make is whether we want to have immunity or not, when that encounter happens.”

Schooley noted that getting that second dose is also exceedingly important. Studies are showing that those who receive just one dose of the Pfizer or Moderna vaccine have significantly less delta protection.

“One injection of an mRNA vaccine is like wearing half of a seatbelt,” Schooley said.

San Diego County has not yet experienced the increase in Delta cases, first detected in India, that Los Angeles County has.

A San Diego County spokesperson said that the total number of such cases detected in the county stood at 18 Tuesday, just two more than were listed in the last report published nearly one week ago.

As of Monday, Los Angeles County, with a population of 10 million, was reported to have confirmed 123 Delta cases for a case rate of 1.2 per 100,000 residents. San Diego’s 18 cases among 3.3 million residents equates to a rate of about 0.53 cases per 100,000 residents.

Barbara Ferrer, Los Angeles County’s public health director, said the new mask recommendation was needed partly because of persistently high numbers of unvaccinated residents, particularly children, Black and Latino residents and essential workers.

Los Angeles County estimates 4.9 million people are fully vaccinated, representing 48.7 percent of its total population.

In San Diego County, nearly 1.9 million are fully vaccinated, representing about 55.5 percent of its residents. (San Diego’s numbers encompass all residents age 12 and older while L.A. puts the threshold at age 16.)

Delta circulation has increased rapidly since the variant grabbed a foothold in California. As of June 23, the variant made up 14.5 percent of coronavirus cases analyzed over the course of that month.

In May, the proportion of sampled cases that were Delta was 4.7 percent, and in April it was a scant 1.8 percent.

But on Tuesday, Dr. Tomás Aragón, director of the California Department of Public Health and the state’s public health officer, said the variant currently “accounts for approximately 23 percent of cases sampled in California, and we anticipate this percentage will increase.”

In the United States, the variant now accounts for 1 in 5 infections.

But the Delta variant’s trajectory outside the U.S. suggests that concerns are likely to intensify.

Countries in the Asia-Pacific region are now reimposing restrictions and stay-at-home orders as the variant drives new surges. Four Australian cites have reimposed lockdowns, and Monday, the Malaysian government said nationwide stay-at-home orders would be extended indefinitely.

Even Israel — which has one of the highest vaccination rates in the world and is aggressively immunizing younger adolescents and teenagers who qualify — has reinstated masking requirements in public indoor spaces and at large public gatherings outdoors, after hundreds of new COVID-19 cases were detected in recent days, including among people who had received both doses of the Pfizer vaccine.

This is not the first time the world has been consumed by a more contagious variant of the coronavirus. The Alpha variant walloped Britain and brought the rest of Europe to a standstill earlier this year. In the United States, Alpha quickly became the dominant variant by late March, but the rapid pace of vaccination blunted its spread, sparing the nation a big surge in infections.

Even now, roughly half of Americans are not vaccinated, and a wide swath of the country remains vulnerable to outbreaks of the virus and its variants. Vaccines for children under age 12 are not likely to be authorized until the fall, at the earliest.

In many Indian states and European nations, Delta quickly outpaced Alpha to become the dominant version of the virus. It is on track to do the same in the United States.

The New York Times and the Los Angeles Times contributed to this report.