SAN FRANCISCO (KRON) — San Francisco’s first mass vaccination site was already booked up hours before opening on Friday morning.

The City College of San Francisco’s drive-thru site (main campus) is accepting COVID-19 vaccine appointments for residents who are in Phase 1a of the priority plan — there is no drop-in availability.

According to San Francisco, it is limited to:

  • Doctors
  • Nurses
  • Paramedics
  • Service workers
  • Long-term care residents
  • People who are age 65 and older

There are over 200,000 residents who are eligible in San Francisco as part of Phase 1a.

For those who have a confirmed appointment, all they need to do is drive up and hang their arm out of the car window to get the first shot. Vaccination staff will have the person remain on scene for 15 minutes to ensure there are no severe reactions to the vaccine.

The city college site is one of three in a system of vaccination centers opening around the county. The other two are in SoMa at the Moscone Center, and in Bayview at the SF Market.

Officials said the location of the first sites is based on rate of COVID-19 infection: “the highest rates of infection are in the Southeast sector of the city, and the City has selected the locations of vaccine sites so they are easily accessible to the residents of these neighborhoods.”

These “high-volume vaccine sites” are operating in partnership with health care providers, the department of public health, and the COVID-19 Command Center.

Each person will need to return to a vaccine site for their second dose about 3-4 weeks later.

The city debuted a notification system where residents can sign up to be alerted when they are eligible to get the COVID-19 vaccine. This follows the prioritization plan, and also is based on vaccine supply, so it could be months before some get their green light to book an appointment.

So how does the vaccine work?

According to the city and county of San Francisco, “the vaccine teaches our cells to make harmless proteins that look like the virus.  Your immune system recognizes that this protein does not belong, and builds an immune response to get rid of it. Your immune system can then fight the real virus if you are exposed later.”

As of Thursday in California, 4.1% of the statewide population received their first dose of the vaccine — but it’s not effective until both doses have been taken. About 0.7% of the statewide population is fully vaccinated.