By Len Ramirez

SAN JOSE (KPIX) — California has passed a grim milestone in the coronavirus pandemic: there have now been one million Californians infected with the virus.

The latest spike in cases comes at a crucial time for fighting the virus: the holidays.

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“The holidays are really coming at a terrible time in this pandemic,” said Dr. John Swartzberg of U.C. Berkeley, who is a leading infectious disease specialist.

Eight months into the pandemic, health officials say we understand more about how the virus is spread.

“We know that the highest risk for transmission is to be inside with others without your mask,” said Betty Duong, a spokesperson for the Santa Clara County Department of Public Health.

“Stay outside, keep your face mask on and maintain your social distancing,” she said to avoid getting the virus.

One other thing health officials have learned during the pandemic is that infected people without symptoms can spread it.

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And, with colder weather forcing more people inside and people gathering up for the holidays — all in the midst of a growing surge of cases — it could be a deadly combination.

Dr. Swartzberg says asymptomatic spread could prolong the surge through winter.

“People feel fine, they think they are fine and they go out and do things with other people and that’s how it’s spreading,” he explained.

Dr. Swartzberg says people should be tested frequently. Health officials are also encouraging people to downsize holiday gatherings to single households or no more than two or three households for outside gatherings.

Some are already planning to do it.

“Everything’s simpler but we got to be safe, specially for the elderly people,” said Susan Pinheiro, who plans to downsize her Thanksgiving gathering from 35 people to 8.

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“Most people that we hang out with take it pretty serious but I know there’s a lot of young people that are doing things I wouldn’t do,” Pinheiro said.