• COVID-19 Vaccine

    Updated April 16, 2021

    The Latest: Johnson & Johnson Vaccine Pause

    The CDC and FDA have recommended a pause in the administration of the Janssen (Johnson & Johnson) vaccine to allow for the ACIP to review data following six cases of a rare and severe type of blood clot (cerebral venous sinus thrombosis) and thrombocytopenia that occurred in women aged 18-48 with symptoms presenting 6-13 days after vaccination.

    No cases have been reported among individuals who have received the Pfizer/BioNTech or Moderna vaccines. Additionally, this pause allows for the CDC to communicate with clinicians. This page will be updated with additional information as it is available.

    While this is a very rare event, CDC is recommending individuals who have gotten the Janssen vaccine to seek urgent medical care if they have symptoms including severe headache, backache, new neurological symptoms, severe abdominal pain, shortness of breath, leg swelling, petechiae or bruising. Additional recommendations for clinicians have been provided. Read more.


    If clinicians are caring for patients with a thrombotic event and thrombocytopenia after the Janssen vaccine, CDC is recommending:

    • Evaluate initially with a screening PF4 enzyme-linked immunosorbent (ELISA) assay as would be performed for autoimmune HIT. Consultation with a hematologist is strongly recommended.
    • Do not treat patients with thrombotic events and thrombocytopenia following receipt of J&J COVID-19 vaccine with heparin, unless HIT testing is negative.
    • If HIT testing is positive or unable to be performed in patient with thrombotic events and thrombocytopenia following receipt of J&J COVID-19 vaccine, non-heparin anticoagulants and high-dose intravenous immune globulin should be strongly considered.
    • Report adverse events to VAERS, including serious and life-threatening adverse events and deaths in patients following receipt of COVID-19 vaccines as required under the Emergency Use Authorizations for COVID-19 vaccines.

    View the AAFP's Johnson & Johnson COVID-19 Vaccine Update webpage for additional details. We are monitoring the situation closely to understand implications for your patients and community. 

    About the COVID-19 Vaccines

    To date, no COVID-19 vaccine candidates have been approved (licensed) by the FDA. The FDA issued emergency use authorizations for three vaccines. EUAs were given for mRNA vaccines from Pfizer/BioNTech and Moderna in December 2020. The third EUA was issued on February 27, 2021 for the Janssen (Johnson & Johnson) COVID-19 vaccine, which uses a non-replicating adenovirus vector. Read more

    All three of the authorized COVID-19 vaccines have been recommended by the CDC’s Advisory Committee on Immunization Practices, which was reviewed and approved by the AAFP. All three vaccines are effective at preventing COVID-19 disease, hospitalizations and death. Encourage your patients to take the first vaccine available to them. Reference the updated efficacy and safety data overview, plus resources and patient education from the FDA and the CDC’s ACIP.

    View the CDC's Interim Clinical Considerations for information on the different vaccines, including clinical considerations, preparation and storage. 

    • What are the guidelines for vaccinated patients? The CDC 's Guidance for Vaccinated People outlines when people are considered fully vaccinated and what activities they can participate in.
    • What do we know so far about the variants and their impact on vaccines? Read more below. 
    • Need an easy resource to support staff conversations? Borrow slides from our sample COVID-19 presentation 
    • Thinking about what your patients will ask? Our COVID-19 Vaccine FAQs and COVID-19 Vaccine Myths can help. 


    Variants and Impact on COVID-19 Vaccines: What We Know So Far

    Virus mutations are common, so it's not surprising that SARS-CoV-2 variants have been detected. The CDC is monitoring these variants and tracking their spread across the U.S., as well as the effect on infection and disease. Researchers are also rapidly checking vaccine effectiveness against the different variants. 

    It is important to note that all the variants appear to have increased efficiency in spreading from person to person so the use of mitigation measures like masks, ventilation, hand washing, physical distancing, and quarantine are paramount.

    A Variant Classification scheme that defines three classes of SARS-CoV-2 variants has been developed and information for the different variants is provided at the links below:

    The B.1.1.7, B.1.351, P.1, B.1.427, and B.1.429 variants circulating in the United States are classified as variants of concern. Use the CDC's map to see where the different variants are found in the U.S.

    Vaccine Availability

    The CDC and other federal agencies are working to distribute vaccine doses to states and jurisdictions. At this time, limited vaccine quantities are available, so vaccine appointments may be difficult to find as more states open slots to all eligible individuals. 

    CDC has provided a vaccine finder to assist in finding locations with available vaccine at . Additionally, many jurisdictions have provided phone numbers to aid individuals without access to internet. 

    • A list of state-by-state distribution plans and federal vaccine sites, and a map from the National Academy of State Health Policy, are available on the COVID-19 Vaccine Distribution page. 
    • The CDC's COVID-19 Data Tracker is also tracking the number of vaccines distributed and administered by state.  

    Interested in how we're advocating on vaccine distribution issues? The AAFP is working to ensure that family physicians are prioritized in federal and state vaccine strategies. Learn more about these efforts on our Vaccines and Immunizations Advocacy Hub

    New Criteria: Quarantine for Vaccinated Persons

    Additionally, the CDC has issued updated guidance on quarantining after an exposure for vaccinated individuals. Note that while mRNA COVID-19 vaccines have demonstrated high efficacy at preventing severe and symptomatic COVID-19, there is currently limited information on how much the vaccines might reduce transmission and how long protection lasts. In addition, the efficacy of the vaccines against emerging SARS-CoV-2 variants is not known. 

    At this time, vaccinated persons should continue to wear a mask, practice physical distancing, practice hand hygiene and other public health measures. However, vaccinated persons with an exposure to someone with suspected or confirmed COVID-19 are not required to quarantine if they meet all of the following criteria: 

    1. Are fully vaccinated (i.e., ≥2 weeks following receipt of the second dose in a 2-dose series, or ≥2 weeks following receipt of one dose of a single-dose vaccine)
    2. Are within 3 months following receipt of the last dose in the series
    3. Have remained asymptomatic since the current COVID-19 exposure

    Persons who do not meet all three should continue to follow current quarantine guidance after exposure to someone with suspected or confirmed COVID-19. 

    FDA Approval Process

    The FDA released guidance for manufacturers to request approval for EUA of a COVID-19 vaccine. The standards for EUA for the vaccine will be stricter than those for other products and vaccine candidates must meet prespecified efficacy and safety data with at least two months of follow up. Additionally, under an EUA, the FDA will continue to collect safety and efficacy data as the vaccine is made available to the public. All data will be reviewed by experts in vaccinology and the CDC’s Advisory Committee in Immunization Practices. 

    Find a list of other vaccine candidates and phase of development in a World Health Organization report.

    AAFP member, Jennifer Middleton, MD, MPH, also wrote a blog on what's ahead with additional vaccines in "Here come the COVID vaccines"

    Coding and Payment

    The American Medical Association published the first set of COVID-19 vaccine and administration codes. Their unique structure allows for tracking and accommodating multiple COVID-19 vaccines.  

    CDC's COVID-19 Vaccine Resources

    Check out information on the CDC's COVID-19 site, including:

    Expect updates to this site, plus CDC’s Vaccination and Immunization site, as more information is available. It's critical that jurisdictions and federal entities receiving vaccine have information to implement an effective COVID-19 vaccination program.