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How COVID Vaccines are Made
How Would COVID Vaccines Work in Your Body?

Eventually everyone who wants a vaccine will be able to get one. However, when the vaccine is first available there will be limited supply. This means that the vaccine initially will be limited to specific populations that are at highest risk of either getting COVID-19 or having serious health problems if they are infected with COVID-19, such as healthcare workers, older adults living in nursing or assisted-living facilities, and other essential workers.

The Washington State Department of Health (DOH) has provided vaccine to a growing number of hospitals, pharmacies, and health systems who enrolled to receive vaccine. DOH and Public Health – Seattle & King County are working with many partners to rapidly scale up the number of vaccination sites and increase access to vaccination.

As of January 18, 2021, Washington State Department of Health has opened vaccine distribution through Phase 1b1.

Vaccination is currently open for people who are:

  • Eligible for Phase 1a: all workers at risk of acquisition or transmission of COVID in healthcare settings; long-term care facility staff and residents; and home health and care aides.

  • Eligible for Phase 1b1:
    • Age 65 years and older
    • Age 50 and older if they live in a household where two or more generations live, (such as an elder and a grandchild), and meet these qualifications:
      • Cannot live independently and receives support from a relative or caregiver (paid or unpaid) or someone who works outside the home
      • Lives with and cares for a young child, like a grandparent with a grandchild.

Not eligible in this phase:

  • Someone younger than 50
  • Someone 50 and older who cares for a partner or friend
  • An older adult who is able to live independently and is taking care of their kin/children.

Learn more about eligibility and getting vaccinated in King County.

  • COVID vaccine will be covered by Medicare, Medicaid and most private insurance, and the cost of the vaccine will be covered for people who are uninsured. There may be a copay or office visit fee, depending on your insurance plan or the doctor you see to get vaccinated.
  • Public Health also is planning free vaccination clinics when supplies of vaccine are available.

Safeguards to ensure that vaccines meet standards for safety and effectiveness include:

Clinical trials


COVID-19 vaccines must go through rigorous clinical trials in which many thousands of study participants receive the vaccine. The Food and Drug Administration (FDA) evaluates the scientific data from these studies to determine the safety and effectiveness of each vaccine. FDA relies on analysis and recommendations from an advisory group of independent scientists and experts, the Vaccines and Related Biological Products Advisory Committee (VRBPAC). VRBPAC meetings are open to the public.

If a vaccine meets the FDA's safety and effectiveness standards, the FDA can make the vaccines available for use in the U.S. by traditional licensure or emergency use authorization.

After the FDA makes its determination, a second independent advisory body of immunization experts, the Advisory Committee on Immunization Practices (ACIP), will review the vaccine's safety and effectiveness data. They will make recommendations to the CDC with guidance for healthcare providers and the public about the use of the vaccine.

Vaccine Safety Monitoring


After any vaccine is authorized for use, including COVID vaccines, multiple safety monitoring systems are in place to watch for possible side effects. If an unexpected serious side effect is detected, experts work as quickly as possible to determine whether it is a true safety concern. This serves as an ongoing evaluation of safety even after the clinical trials are completed. For COVID-19 vaccine, the CDC and FDA have expanded safety monitoring systems to carefully evaluate safety in real-time and make sure the COVID-19 vaccines are as safe as possible.

Only licensed and trained health professionals can give vaccinations


Only individuals who are licensed and trained to administer vaccines will be able to provide vaccination. Once the vaccine is more widely available to the general public, many different types of healthcare providers will provide vaccine in order to make the vaccine accessible for all who are interested in receiving it. These providers may administer vaccine both in clinics and hospitals and at more mobile or pop-up events in the community.

  • A safe and effective vaccine against COVID-19 is a major break-through. But vaccine alone won't end the pandemic right away.
  • Even after a vaccine is available, stopping the pandemic will continue to require everyone – even if vaccinated - to continue to follow all current guidance to protect themselves & others, including wearing a mask, staying at least 6 feet away from others, limiting activities outside the home and avoiding crowds, washing hands often, following CDC travel guidance, and following quarantine guidance after an exposure to someone with COVID-19.

Our aim in King County is to efficiently and equitably vaccinate as many eligible King County residents as possible in order to suppress the spread of COVID-19 and minimize the impact of the pandemic on our community.

Link/share our site at www.kingcounty.gov/covid/vaccine