On October 21, 2021, the Centers for Disease Control and Prevention (CDC) officially recommended Moderna and Janssen (J&J) COVID-19 vaccine booster doses for people at higher risk for COVID-19. With these expansions to the Emergency Use Authorizations for Moderna and J&J, there are now booster recommendations for all three available COVID-19 vaccines in the United States. Notably, CDC also authorized a “mix and match” approach to booster doses.

Similar to its Pfizer booster recommendations, CDC recommends COVID-19 vaccine booster doses for everyone who completed a Moderna primary series and is over age 65, people whose work puts them at high risk of contracting COVID-19, and people age 18 and older based on their own decision relating to their risk from COVID. CDC recommends a COVID-19 booster dose for anyone age 18 and older who completed their primary series with a dose of J&J vaccine. With the high risk of exposure in Colorado, it is our hope that everyone receives a booster six months after Moderna or Pfizer and two months after J&J. Consultation by the

State’s Chief Medical Officer with the CDC confirms that offering the vaccine to anyone in the state who is over 18 and is due for their booster is allowed given the high rate of disease transmission in Colorado.

Booster doses have been demonstrated to significantly improve protection against COVID-19 infection, severe disease and death. These expanded booster dose authorizations are an important step in ensuring Coloradans most at-risk for severe COVID-19 outcomes have the greatest protection possible. Research continues to show waning immunity against infection with the primary series beginning 4-6 months after completion. While vaccinated persons remain protected against hospitalization, infection and transmission can occur among

Colorado’s vaccinated persons. Almost eight in ten hospitalizations are among the unvaccinated. Transmission of COVID-19 by vaccinated Coloradans experiencing waning immunity may prolong the increasing case numbers, spreading to the unvaccinated, with subsequent hospitalization, and limit our state medical/surgical bed supply. Increasing the administration of boosters is one of a number of strategies to help slow the spread of this pandemic in Colorado over the next six weeks.

We urge all COVID-19 vaccine providers to offer boosters to all persons 18 and older as soon as possible if the appropriate duration has passed since their initial series. Please review this letter in its entirety for additional guidance on booster administration. REMEMBER: individuals still do not need to present an ID, insurance, proof of medical history or proof of employment to receive a booster. Boosters are free for everyone. Individuals can self-attest (e.g., self-report they are eligible) and receive booster doses. Nobody should be turned away from receiving a booster dose.

Booster Dose Eligibility

While CDC made specific recommendations about certain groups who should get a booster dose, they also offer wide flexibility in terms of an individual’s benefit-risk assessment considerations for receiving a booster dose that essentially include everyone in a state with high risk of exposure like ours. Individuals may consider the following risk factors in their decision making to seek a booster dose:

• Risk of exposure to SARS-CoV-2: Factors that would be expected to affect the risk of exposure to SARS-CoV-2 include work or residence in certain settings; level of community transmission; rates of COVID-19 vaccination in their community; and the likelihood of frequent interactions with possibly unvaccinated people from outside an individual’s household, and adherence to current prevention measures.

• Risk for developing SARS-CoV-2 infection: A person’s risk for developing SARS-CoV-2 infection may vary based on time from completing a primary COVID-19 vaccine series and time from prior SARS-CoV-2 infection due to waning immunity.

• Risk for severe infection related to underlying conditions: A person’s risk of developing severe

COVID-19 may vary by the type, number, and level of control of specific medical conditions as well as other yet to be defined variables.

• Potential impact of SARS-CoV-2 infection: SARS-CoV-2 infections that are not severe may still lead to morbidity (e.g., post- COVID-19 symptoms). A person’s individual circumstances should also be considered; these may include living with or caring for a person who is medically frail or immunocompromised or a child who is not eligible for COVID-19 vaccine, or the inability to work or meet other personal obligations when infected, even if not severely ill with COVID-19.

Amended Public Health Order 21-01

Colorado Department of Public Health and Environment (CDPHE) has amended Public Health Order 21-01 Vaccine Access and Data Reporting for COVID-19. All COVID-19 vaccine providers are required to follow the Public Health Order (PHO). Newly added to the PHO include the following requirements:

COVID-19 vaccine providers must administer second, additional and booster doses to individuals regardless of where those individuals may have received previous doses.

COVID-19 vaccine providers must administer booster doses to individuals who self-attest to meeting booster dose eligibility criteria.

Items of Note about Boosters

• Individuals still do not need to present an ID, insurance, proof of medical history or proof of employment to receive a booster. Boosters are still free and people do not need to be a resident of Colorado, or of a particular county, to receive a booster.

• Individuals can self-report their eligibility and receive a booster dose wherever COVID-19 vaccines are offered. This will help ensure there are not additional barriers to access for those seeking booster doses.

• As previously recommended, moderately to severely immunocompromised individuals

who are eligible for an additional dose of an mRNA vaccine should get that dose at least 28 days after the completion of their primary series.

• ACIP recommends that the additional dose be the same mRNA vaccine that people received for their primary series, but receiving either mRNA vaccine is acceptable.

• People 12 - 17 who are moderately to severely immunocompromised can only receive the Pfizer vaccine for their additional dose.

• Moderately and severely immunocompromised individuals aged 18 and older who completed an mRNA COVID-19 vaccine primary series and received an additional mRNA vaccine dose may receive a single COVID-19 booster dose (Pfizer-BioNTech, Moderna, or Janssen) at least 6 months after completing their third mRNA vaccine dose.

• In such situations, people who are moderately and severely immunocompromised may receive a total of four COVID-19 vaccine doses.

• The definition of “fully vaccinated” does not change with the expanded booster dose authorizations.

• People are still considered fully vaccinated two weeks after their second dose of Pfizer or Moderna vaccine, or two weeks after their single dose of J&J vaccine.

• This definition applies to all people, including individuals who are moderately to severely immunocompromised who receive an additional dose at least 28 days after completing their initial primary series.

• Coadministration of Boosters with Other Vaccines

COVID-19 vaccine boosters, along with the primary series, may be given with other vaccines without regard to timing.

• This includes simultaneous administration of COVID-19 vaccines and other vaccines on the same day.

• If multiple vaccines are administered at a single visit, administer each injection in a different injection site at least one inch apart from each other.