SAN JOSE (SAN JOSE SPOTLIGHT) – COVID-19 infections are on the rise in Santa Clara County again, and officials are urging residents to masks up–even in some outdoor settings.

In recent days, the county has reported more than 1,000 new daily COVID infections, officials said, noting the actual tally is likely much higher due to underreported test results. The current seven-day rolling average, at 1,094, is comparable to the spike in cases in May. The hospitalization rate has also jumped significantly in the past month with 233 coronavirus patients–the highest since the first wave of omicron infections in January.

“These are all indicators that the virus remains highly prevalent in the community,” Dr. Sarah Rudman, the county’s assistant health officer, told San Jose Spotlight. “We are fortunately seeing that current cases admitted for COVID-19 tend to be less serious than in the past.”

The surge in cases and hospitalizations comes as the county and country grapple with a new COVID subvariant, BA.5. This subvariant has quickly become the most dominant strain in the U.S. Rudman said it makes up more than half the samples collected from wastewater locations in Santa Clara County. The county first discovered the strain in its wastewater system in June.

BA.5, along with its close relative BA.4, is a subvariant of the omicron variant.

BA.5 originated from South Africa and is believed by experts to be the most transmissible strain, with a potential of reinfecting those who have survived earlier omicron infection. Some are concerned about the uptick in hospitalizations, but Rudman said the severity of the subvariant is yet to be fully understood. Santa Clara County has not seen an uptick in deaths caused by COVID-19 recently.

“This is a big problem,” Dr. Hector Bonilla, clinical associate professor at Stanford Medicine, told San Jose Spotlight. “We need to go back to COVID 101. We need to avoid having too many people around you and find a good mask when you’re in public.”

This subvariant has the ability to evade the immune system, even among the vaccinated and boosted population, he said, adding he expects a new vaccine will come later this year to address the new strain. Bonilla said experts are still studying the impact of the new strain, urging residents to be as careful as possible.

“Even with mild disease, you can still have long COVID,” he said, adding experts still don’t fully understand the impact of long COVID, especially for young children. “We don’t what will happen to the brain of the kids with long COVID five years from now.”

So far, county officials are not planning to reinstate restrictions or a mask mandate, but urge residents to take precautions as they head into summer activities. Santa Clara County used to have some of the strictest COVID-19 mandates, but those have been relaxed since March.

“We, along with the state of California, continue to strongly recommend masking, especially when indoors, but also when outdoors in large gatherings where people are in close contact with one another,” Rudman said. “Well-ventilated places, especially outdoors, are safer than indoor areas with poor air circulation.”

Santa Clara County–and the Bay Area in general–is still in a good spot to fight the new variant due to its high vaccination rate. As of Friday, 86.3% of all residents in the county are vaccinated and more than one million– over half the county– people have received a booster shot, county data shows.

The county also started administering COVID-19 shots to infants and toddlers last month.

Local health officials and experts said vaccines and boosters remain the best defense against severe infection, serious illness, long COVID and death.