AMARILLO, Texas (KAMR/KCIT) – Booster doses of COVID-19 vaccines have been recommended by the Centers for Disease Control and Prevention (CDC) for many, and eligible patients are allowed to choose to receive any of the FDA-approved versions (Pfizer-BioNTech, Moderna, or Janssen). However, with some immunocompromised people recommended to have an initial vaccination series of three doses, there is some confusion with how many doses of a COVID-19 vaccine someone should have in total.

Here is a breakdown, according to the CDC vaccination guidelines and resources, of who might get a COVID-19 vaccine series of two doses, who may get three, who might get a booster, and when:

|| The initial COVID-19 vaccination series – the “Primary Series” ||

Currently, everyone that is 12 years of age or older is eligible to get a COVID-19 vaccine. Most people will get an initial vaccination series of two shots, either two doses of Pfizer three weeks (21 days) apart or Moderna four weeks (28 days) apart. Those who receive the Johnson & Johnson vaccine only need one dose.

People in this category who receive a COVID-19 vaccination series are considered fully vaccinated two weeks after their second shot in a Pfizer or Moderna series, or two weeks after the single-shot Johnson & Johnson vaccine series.

However, immunocompromised people may receive an initial vaccine series of three doses. This means that a person who gets an initial vaccination series in this category would get a third dose of Pfizer or Moderna around four weeks (28 days) after the second dose. A fully vaccinated person who is immunocompromised, then, might end up with a total of three shots in their initial series.

These third doses, according to the CDC and Johns Hopkins, are the same as the first two doses.

People who might get a third dose initially include:

  • People who are considered moderately or severely immunosuppressed;
    • In active cancer treatment for tumors or cancers of the blood
    • Received an organ transplant and are taking medication that supresses the immune system
    • Have either had a stem cell transplant within the last two years or are taking medicine to suppress the immune system
    • Were diagnosed with DiGeorge syndrome or Wiskott-Aldrich syndrome
    • Are diagnosed with HIV and have a high viral load or low CD4 count, or are not currently taking medication to treat HIV
    • Are taking drugs such as high-dose steroids or other medications that may cause severe suppression of the immune system
  • People who have spoken with their medical providers, especially if they’re unsure if they belong in the above groups, and been recommended for a third initial vaccine dose series

|| COVID-19 Booster Doses ||

A booster dose is different from an additional dose. While some people may have their initial, or primary, vaccination series include an additional dose bringing them to three total doses, booster shots are a dose given to people after the protection from the initial vaccination series has started to wane.

According to the CDC, a “homologous booster dose” is a booster dose that is the same product as the initial vaccine series, and a “heterologous booster dose (mix-and-match booster)” is a booster dose that is of a different product than the initial series. Any of the COVID-19 vaccines can be used as booster doses, no matter what vaccine a person initially received.

Booster shots for people who received an mRNA COVID-19 vaccine (Pfizer or Moderna):

  • These people should get a booster dose at least six months after their initial series was completed;
  • These people may get a booster dose at least six months after their initial series was completed;
    • People aged 18-49 years with certain underlying medical conditions
    • People aged 18-64 with increased risk for COVID-19 because of occupation or institutional settings

Booster shots for people who received the Johnson & Johnson vaccine:

  • People aged 18 or older who got an initial series of the single-dose Johnson & Johnson vaccine should get a single COVID-19 booster dose at least two months (eight weeks) after their initial series is completed

These recommendations also apply to people whose initial series included getting two doses of different mRNA vaccines (Pfizer or Moderna.)

People who are moderately to severely immunocompromised and got an initial vaccination series of three doses are able for a booster dose at least six months after their initial series of three shots is completed.

A full breakdown of the dosing schedule can be found here, on the CDC website.