Giving second COVID-19 vaccine shots may reduce supply for people seeking first dose

A mass COVID-19 vaccination site outside the Forum in Inglewood
A mass COVID-19 vaccination site outside the Forum in Inglewood.
(Associated Press)

Officials across Southern California are opening more sites to administer coronavirus vaccine. But there are concerns that the shortage in vaccine doses could worsen before it gets better.

Authorities have said the biggest problem right now is getting enough vaccine to meet demand. At current rates, it could be June before Californians 65 and over are fully vaccinated. And full vaccination in places like L.A. County might not be possible until 2022.

Dr. Paul Simon, chief science officer for the county Department of Public Health, said Friday that if weekly vaccine shipments were to increase to 500,000 doses, the county could potentially immunize 75% of its adult population by midsummer.


At the current rate, though, he said the “vaccination effort will likely extend well into 2022.”

Another bottleneck has formed because part of the supply of available shots is reserved for second doses within the prescribed three- or four-week time frame. When shortages occur, fewer shots are available for first doses of the vaccine.

That’s certainly the case in L.A. County, where Simon said Friday that he thinks “a majority of the supply next week will go for second doses.”

“There will be some first doses offered, but we want to be very careful, because we can’t predict, unfortunately, the supply chain even several weeks forward,” he said.

Simon acknowledged that there is tension “between wanting to get as many people vaccinated with that first dose [and] with trying to make sure that everybody who’s vaccinated gets the full sequence of two doses.”

He added: “The vaccine trials were done with that two-dose regimen in mind. We know that works. We don’t know exactly what level of protection one gets if there is a delay in that second dose.”


Here is where we stand:

Los Angeles County

Residents 65 and older can sign up for an appointment at the county public health department’s website. Residents without computer access can call (833) 540-0473 between 8 a.m. and 8:30 p.m. for assistance with reservations.

The city of Los Angeles is also offering the vaccine to those 65 or older, through a different online portal. That website connects patients to mass-vaccination sites including Dodger Stadium, San Fernando Recreation Park, Lincoln Park, Hansen Dam Recreation Area and Crenshaw Christian Center.

Orange County

Orange County is opening its second large-scale COVID-19 vaccination site Saturday at Soka University in Aliso Viejo. The county launched its first vaccination center at Disneyland in Anaheim.

Eventually, the county plans to operate five centers, which health officials say is key to their goal of getting all residents vaccinated by July 4.

For now, only healthcare workers, residents of long-term care facilities and people 65 and older are eligible to be vaccinated at the centers.

But ramping up vaccinations has been hindered by supply problems. The county is dependent on the state for its share of vaccine doses and has been asking for more daily, officials said.


San Diego County

After a sluggish start to San Diego County’s COVID-19 vaccine rollout, the region has received 173,000 doses over the past few days, coinciding with the launch of a mass-inoculation site in Chula Vista on Thursday.

Sharp HealthCare will run the site, located in a former Sears department store, from 10 a.m. to 7 p.m., seven days a week. County Supervisor Nora Vargas said that 1,800 people made appointments Thursday, and a Sharp representative added that the site will vaccinate 5,000 people a day by next week.

It’s the second effort of its kind in the county. The first, run by UC San Diego at the Petco Park tailgate parking lot, has immunized more than 35,000 people, according to Dr. Christopher Longhurst, UCSD Health’s chief information officer.

Unlike the site near Petco Park, the Chula Vista location will be walk-in rather than drive-through, though appointments are necessary. It’s the first vaccine site in the South Bay, which has been hit hard by the pandemic. National City and Chula Vista have the highest and third-highest coronavirus infection rates, respectively, among the county’s cities.

Inland Empire


Information for Riverside County residents can be found at the Riverside University Health System, while San Bernardino County residents can consult the county’s website. Both counties are offering vaccines with various restrictions at multiple locations.

Ventura County

Ventura County is offering vaccinations to residents 75 and older, who can sign up for appointments online or by calling (805) 477-7151.