CDC Announcement, August 13, 2021: Booster Shots for Immunocompromised Individuals

CDC now recommends that people whose immune systems are compromised moderately to severely should receive an additional dose of mRNA (Pfizer or Moderna) COVID-19 vaccine after the initial 2 doses. There is not enough data at this time to determine whether immunocompromised people who received the Johnson & Johnson’s Janssen COVID-19 vaccine also have an improved antibody response following an additional dose of the same vaccine. Read CDC’s statement.

  • People who are moderately to severely immunocompromised are especially vulnerable to COVID-19 because they are more at risk of serious, prolonged illness.
  • People who have compromised immune systems may benefit from an additional dose to make sure they have enough protection against COVID-19.
  • CDC recommends people who are moderately to severely immunocompromised should receive an additional dose of mRNA COVID-19 vaccine after the initial 2 doses.
  • CDC recommends that people with moderately to severely compromised immune systems receive an additional dose of mRNA COVID-19 vaccine at least 28 days after a second dose of Pfizer-BioNTech COVID-19 vaccine or Moderna COVID-19 vaccine.
  • CDC does not recommend additional doses or booster shots for any other population at this time.

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While some countries are offering a third dose of COVID-19 vaccine to immuno-compromised individuals, no additional doses (boosters) are recommended for fully vaccinated Americans at this time. Mesa County Public Health (MCPH) will not offer COVID-19 booster vaccines until official guidance is released.

We are still learning how long COVID-19 vaccines can protect people. Research is ongoing at the federal level. In-depth studies from the National Institutes of Health (NIH), Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA) are underway to evaluate the necessity of boosters, primarily for immuno-compromised individuals. The CDC and FDA released a statement stating they “are prepared for booster doses if and when the science demonstrates that they are needed.” At this time, no federal authorization for a third shot or booster has been authorized. 

The Pfizer, Moderna, and Janssen (Johnson & Johnson) vaccines at currently recommended intervals are effective in preventing severe illness and hospitalization due to COVID-19 including the Delta variant, and all circulating variants. Current guidance suggests that full protection is achieved after being fully vaccinated. People are considered fully vaccinated: 

  • Two weeks after their second dose in a two-dose series, such as the Pfizer or Moderna vaccines, or
  • Two weeks after a single-dose vaccine, such as Johnson & Johnson’s Janssen vaccine.

If you don’t meet these requirements, regardless of your age, you are not fully vaccinated and should keep taking all precautions.

It is important to distinguish between the second dose in a two dose series and a booster.  While a booster is not recommended at this time, completing your vaccination series and getting both shots of the Moderna or Pfizer vaccine is critical to ensure full protection from COVID-19.  


Getting a COVID-19 vaccine is free, easy and more accessible than ever. The MCPH Community Vaccination Site, located at 510 29 ½ Road, accepts walk-ins. The Power the Comeback vaccine bus makes routine stops at densely populated locations across the Western Slope, and MCPH offers a mobile clinic as well as scheduling for a COVID-19 vaccine clinic at workplaces or events.

Visit our website for clinic hours and locations.