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COVID-19 Information: Santa Clara County and Bay Area, California

Trustworthy information about COVID-19

Who is currently eligible to be vaccinated?

California state government (working with federal health agencies) determines who is eligible to get vaccinated. For current information, see:

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Vaccine and Booster Updates for the Bay Area


New vaccine formulas from Pfizer / BioNTech and Moderna have been approved Sept. 13, 2023 for everyone over 6 months old. It is expected to be endorsed by the FDA soon, and could be available in pharmacies and medical offices as early as Monday Sept. 18, 2023.

These webpages will be updated when more details are known - check back often.

Getting COVID Vaccinations in the Bay Area

Getting the vaccine - make an appointment or find a walk-in location:


Starting May 2023, health insurance companies have been rolling COVID vaccines into their medication coverage plans. There should still be no charge to get vaccinated, but there may be limits on where and how we can get them. Per the Your Local Epidemiologist blog:

"Private insurance companies are mandated to cover this vaccine with no copay. What has changed since last year? Insurers are no longer required to pay for “out-of-network”. You may need to get your vaccine at your doctor’s office if your pharmacy is not in-network with your insurance plan.

Uninsured or underinsured adults: CVS/Walgreens are required by federal law to cover your vaccine at no cost to you, thanks to the new Bridge Program. This is just for COVID, not for RSV, unfortunately. 

Uninsured or underinsured kidsVaccines for Children cover all kids' vaccines, not just COVID, for those that cannot pay."

Vaccinating Kids and Teens: 

In Santa Clara County, children 5 and older can get vaccines and boosters at any of the locations where adults are vaccinated. Children younger than 5 years old should be vaccinated at their pediatrician's office. For Santa Clara County residents, if your child does not have a regular doctor, call (866) 967-4677 for assistance enrolling in government programs or health coverage.

Vaccinating any child or teen requires permission of their parent or legal guardian (with some exception for teens 12+). The permission form is online, or can be filled out on location.

When's the Best Time to Get a COVID Booster Vaccine?

It makes sense to optimize the timing of when to get vaccinated against COVID to give the strongest and most long-lasting protection, but there isn't clear guidance. Some of the factors to consider are:

  • Immune system protection against COVID infections, from both vaccines and from catching COVID, dwindles over time.
  • Recovering from COVID does boost our immune system response against infection for some months; getting vaccinated too soon could just be redundant.
  • While most experts are guessing that peak COVID season will be in fall and winter months, we have no idea if we'll see a surge at other times of the year, like with the Omicron variant.
  • (Also, we can't know whether additional booster doses of COVID vaccine will be available in the 2023-2024 season, or if the current version that was approved in September 2023 is it, until the next version comes out in fall 2024.)

Current advice from CDC and other experts to people who have recently recovered from COVID:

  • Who are over 65, OR  who are at risk for severe disease, can wait up to 3 months after recovering from COVID (or from the last vaccination dose). Waiting longer may not be harmful, but definitely get vaccinated within 6 months after last infection or last vaccination.
  • Who are under 65 AND are not also medically vulnerable can wait 6 months, and maybe more after recovering from COVID or from the last vaccination dose.
  • But at the same time it's wise for everyone to get vaccinated before infections peak (expected to be sometime in late October / early November) if possible, before winter holidays or travel.

What Happens After Getting a Vaccine?

Information on the side effects of these vaccines, and precautions to take:

one person pointing to recent vaccination + health care worker, from Santa Clara County Dept. of Public Health.

After getting vaccinated, sign up with the CDC's reporting system to record your reactions, and help to push our knowledge of how to treat this novel disease forward. Sign up after the first dose, for 2-part vaccines or after the 1-shot version.

Getting vaccinated now does not mean we can immediately go back to our pre-pandemic life. The hope is vaccines will save lives and keep fewer people from getting seriously ill, but they probably will not be able to stop the pandemic in its tracks quite yet. People who have been fully vaccinated (at least 14 days after their last vaccine dose) have fewer restrictions on wearing face masks and distancing, in some situations. (See the page in this guide for Slowing the Spread for details on where vaccinated people still need to take precautions.

We are likely to need to keep taking some precautions until young children can be safely vaccinated and until worldwide infection rates are significantly lower.

Available COVID-19 Vaccines

Vaccines previously approved for use in the U.S. are by:

  • from Pfizer / BioNTec, 
  • Moderna
  • Novavax

On Sept. 12, 2023 the CDC's Advisory Committee on Immunization Practice approved new vaccine formulas from Pfizer / BioNTech and Moderna. A new formula from Novavax is currently in the pipeline

Bivalent vaccine (designed to cover both the original form of SARS-CoV-2 and for later variants) replaced the first-generation COVID vaccine at the end of 2022. An updated single vaccine was approved in September 2023 to replace the bivalent vaccine. It is unclear at this time whether the CDC will recommend booster vaccines in 2024, or, like current flu vaccines, it expects a single shot to be effective for most people over the course of the 2023-4 virus season.

First-time COVID vaccination requires two doses approximately a month apart (28 days for the Pfizer vaccine, 21 days for Moderna. Boosters are one single dose.

Proof of Vaccination

Some activities now ask for proof of COVID-19 vaccination to enter or to participate. That could mean showing the card that recorded date(s) and time(s) of vaccination. But it's all too easy to lose that card if it is kept in a wallet or pocket. Instead, wiser to keep that card in a safe place, and use one of these alternatives:

  • make a photocopy of both sides, and keep that close to hand in a pocket or wallet or car; or
  • take a photo of both sides with a smartphone; or
  • (for people in California), get a verifiable QR code link to store on a smartphone or other device using the Digital COVID-19 Vaccine Record.

Please don't laminate your vaccine card - it will be needed to record future doses. Be sure that your proof of vaccination is updated when you get each vaccine booster

If you don't have your original vaccination card with you when getting the next dose, check to make sure that your digital vaccination record - see below - has been updated with that information. If it has not, follow the process for a lost vaccination card to correct your information.

What if you've lost your vaccination card? For people in Santa Clara County, here's advice from our county Public Health Department:

Request vaccine verification from the state

visit the vaccination site (if it is still open)

contact the healthcare provider that administered the vaccine

How Do Vaccines Work? Are They Safe?

Most of us have a really basic idea of how vaccines work: by they sensitive us to a specific disease, so when we're exposed to infection, we are already equipped to fight it off. That's not wrong, but immunity is rather more complex. There are several different types of vaccines; depending on type and depending on the disease, each with their own limitations on how completely they can protect us and for how long.

vaccine safety image, two adults + a child, from the Santa Clara County Department of Public Health.

For a better understanding what vaccines can do for us, see:

How well our bodies resist infection - our immunity, in other words - depends on the strength of the antibodies created in our bodies and on how healthy we are overall. Active immunity (when our bodies create antibodies for ourselves) is stronger than passive immunity (when we are given antibodies from someone else) and also lasts longer.

Vaccine safety is a big concern to many in the U.S. There has been a lot of mis- and dis-information in the last decade on the topic of vaccines, especially vaccines for children. These sources will bust many of those myths:

The Centers for Disease Control and Prevention explains how they will make sure that the COVID-19 vaccines offered to the people of the U.S. are safe:

How Vaccines are Evaluated

With familiar and well-known diseases like whooping cough (pertussis) or polio, we can measure the effectiveness of a vaccine, using past case history and statistics to figure out how many people were not infected because they got the vaccine, compared to unprotected people. 

Effectiveness is impossible to calculate accurately for a new disease like the novel coronavirus. With COVID-19 the best we can do for now is measure efficacy (compare the number of cases in one group that got the vaccine, versus another control group that did not). And as one immunology textbook points out, when we look at vaccines, we are concerned with efficacy in three different areas:

  • Efficacy to prevent infection (also called sterilizing immunity)
  • Efficacy to prevent disease [getting sick and also transmitting the disease to others]
  • Efficacy to prevent severe disease

The currently-available vaccines for COVID-19 are good at the last one, and also the second - but they don't offer sterilizing immunity.

Clinical trials testing efficacy of vaccines need to be as diverse as the population they intend to help. When there's only a small number of people participating in a clinical trial, though, it's hard to have confidence that it will work on more than a narrow slice of the population. The current clinical trials for COVID-19 vaccines being considered in the U.S. are paying attention to that problem; and the National Institutes of Health's All of US program aims to recruit larger and much more diverse groups of people to participate in all kinds of clinical trials, to avoid further bias in healthcare.

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