SAN FRANCISCO (CBS SF) – As 2021 approaches, San Francisco health officials noted the stay-at-home order is starting to have an effect on new COVID-19 cases, but warned residents to avoid New Year’s gatherings.

Public Health Director Dr. Grant Colfax said gatherings, like those at Thanksgiving attributed to fueling the current surge in cases, would result in thousands more people in city hospitals and hundreds more deaths.

“I cannot emphasize enough how catastrophic it will be if people celebrate in ways that we normally do for New Year’s Eve,” Colfax said at Tuesday’s briefing.

“There is more virus out there than ever before. We simply can’t get away with things you may have been able to get away even with in prior surges. It’s one New Year’s Eve. I know it’s been a hard year. But the vaccine is on the way,” the public health director went on to say.

Hospitalizations continue to remain at record highs, with almost 200 people currently in the hospital with COVID-19, nearly double the number hospitalized during the surge in cases over the summer. Colfax anticipates the number of hospitalizations to continue to climb in the coming weeks.

The public health director said there has been some improvement in some metrics since cases started climbing since Thanksgiving, which he attributed to implementing a stay-at-home order ahead of the state in early December.

Average number of new cases per day in the city has dropped to 270 for the first time since December 12, but Colfax stressed that number is still much higher than previous surges and that the full effects of holiday gatherings may not be known until sometime in January. The reproductive rate, a measure on how much the virus is spreading, has dropped from 1.45 on December 5 down to 1.13 on December 26.

While the reproductive rate has dropped, Colfax said that the number needs to be below 1 to stop the virus from spreading.

“By staying home and not gathering, we’ve been able to prevent hundreds of hospitalizations and save so many lives,” Colfax said. “We have done it twice before and I know that we can do it again.

Mayor London Breed echoed Colfax’s calls to stay at home and thanked those who avoided gatherings over the holidays.

“You are saving lives and keeping your fellow San Franciscans safe,” Breed said in a tweet. “It’s critical that we do the same for New Year’s Eve. We can’t lose our progress by having another surge.”

Colfax was also concerned, particularly as travel at San Francisco International Airport and airports across the country has risen to levels not seen since before the pandemic during the holiday season.

“This is extremely concerning and does not bode well for January,” he said.

City residents who travel outside of the Bay Area are being urged to self-quarantine for 10 days upon returning.

At Tuesday’s briefing, the final one of 2020, Colfax expressed condolences to the 182 San Franciscans who died from COVID-19 this year. He also thanked residents and those on the front lines for their efforts in beating back the virus, saying the last few months have been “unimaginable just a year ago” following the first outbreaks of the coronavirus.

“I want to thank San Francisicans for your incredible efforts during these past months,” he said. “And I want to express my incredible gratitude to the medical providers and first responders and everyone who has been on the front lines of this pandemic this year.”