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San Francisco Covid levels spike just in time for holiday travel peak

A security checkpoint as people wait in line and TSA agents checking boarding passes and id's.
A Covid spike is arriving just as holiday travel is expected to peak on Friday.  | Source: Morgan Ellis/The Standard

Covid levels are spiking in San Francisco days ahead of Christmas, with concentrations reaching their highest in weeks, WastewaterSCAN data shows.

The city’s two wastewater treatment plants show a spike in Covid concentrations as of Dec. 20, the latest data available.

Virus levels at the city’s Oceanside treatment plant on the west side have jumped by over 75% between Dec. 17 and Dec. 20, the highest virus concentrations in wastewater since March 15.

A graph shows Covid levels spiking.
San Francisco wastewater shows Covid levels over the last six weeks, with a large spike arriving just as holiday travel is expected to peak Friday. | Source: WastewaterSCAN

Virus concentrations in wastewater collected at the city’s southeast treatment plant spiked more than 73% during the same period and are the highest virus levels since Nov. 30 for that location.

RSV—or respiratory syncytial virus— concentrations at both plants are declining but remain high, according to the data.

The Covid spike comes as holiday travel is expected to peak on Friday

READ MORE: Use Your California DMV Digital Driver’s License This Holiday at SFO, SJC and LAX Airports

Dr. Bob Wachter, UCSF’s chair of medicine and a popular social media presence who often posts Covid advice, took to X on Monday to say he has resumed wearing masks in crowded stores, airplanes or trains, elevators, theaters or anywhere that’s crowded and poorly ventilated, citing a “moderate uptick” in Covid levels.

“When I do mask, I always use an N95; I see no reason to wear a less effective mask,” Wachter said.

Wachter added that he would still enjoy a meal indoors without a mask but would prefer to sit outdoors if it was an option. However, his advice came two days before the spike was seen in city sewage.

You can still get free Covid tests in the mail from the federal government after they resumed the free test program in November. You can order up to eight tests per household.

Boxes of Covid tests lie on a table.
You can order up to eight tests Covid test kits per household. | Source: Brontë Wittpenn/San Francisco Chronicle via Getty Images

The San Francisco Department of Public Health said people should do the following to protect themselves and others from illness this holiday season: 

  • Everyone over the age of 6 months should get both an updated Covid vaccine and this year’s flu vaccine. 
  • People aged 60 and over and pregnant people should ask their providers about the RSV vaccine. All pregnant people should receive the vaccine between weeks 32-36 of pregnancy. 
  • Keep a well-fitted mask on hand for added protection in crowded indoor spaces.   
  • Stock up on Covid at-home test kits. This way, if you feel sick, you can test right away and act quickly to get medicine to stop the illness from becoming serious. Medicine is recommended for most adults and some teens. You must start the medicine within 5 days after starting to feel sick—but as soon as possible is best. 
  • If you think you may have the flu, contact a health care provider immediately to get tested. Flu medicine is recommended for children younger than age 2, adults age 65 and older, pregnant people and people with a variety of health conditions. You must start the medicine within 2 days after starting to feel sick.  
  • Stay home when sick, and stay away from others who are sick.  
  • Increase ventilation or air filtration when indoors if possible. 
  • Practice good hygiene: Wash hands, cover coughs and sneezes, and avoid touching your eyes, nose and mouth. 

Garrett Leahy can be reached at