COVID-19 Vaccine FAQs
Q: What is vaccination?
A: Vaccination is a medical process that is critical to the prevention and control of infectious-disease outbreaks. Vaccines are already used to prevent millions of deaths every year from diseases like tetanus, measles and influenza.
A vaccine is a medical preparation of biologic material that is introduced into the body in order to provide the recipient with immunity (an effective host defense) against an infectious disease.
Q: How do these first COVID-19 vaccines work?
A: Vaccines expose us to pieces of either a bacteria or a virus, which causes our bodies to recognize a potential threat and to mount an immune response. The goal with a vaccine is to help the body prepare for an actual infection, so it is ready to rapidly and effectively eliminate the SARS-CoV-2 virus when exposed to it.
There are different types of vaccines. The Pfizer and Moderna vaccines are called messenger RNA (mRNA) vaccines. The mRNA in the vaccines carry genetic instructions which cells in the body use to make copies of viral proteins. Once your cells make those proteins, your immune system will make the antibodies that bind to the protein, disable the virus, and protect you from getting sick or as sick from this virus.
Q: How do we know that the vaccine is safe and effective?
A: The Food and Drug Administration (FDA) reviews all vaccines for safety before allowing them to be administered to the public. Additionally, The Advisory Committee for Immunization Practices (ACIP), a group of medical and public health experts that advises the Centers for Disease Control and Prevention (CDC), also assesses the safety and effectiveness of vaccines.
Clinical trials of the vaccines lead to an understanding of safety and effectiveness. With the two early vaccines from Pfizer and Moderna, preliminary data suggests they are both about 95% effective. That means that under controlled conditions there were about 95 percent fewer cases of COVID-19 in the group of people who got the vaccine compared to the group of people who got the placebo.
Q: How soon will someone be protected after taking the vaccine?
A: With the two mRNA vaccines, it is estimated that immunity develops around two to three weeks after completing the second shot in the series, but each vaccine works a little differently and every individual responds a little differently.
Both the Pfizer and Moderna vaccines are a two shot series, and it is important that an individual have both shots in order to confer immunity.
Q: How many shots will I need to get?
A: Most of the COVID-19 vaccines currently in phase 3 clinical trials in the U.S. require two (2) consecutive shots, three or four weeks apart, for the vaccine series. Future COVID-19 vaccines may require only one shot. Currently, Pfizer’s vaccine requires two doses in the vaccine series to be given three weeks apart.
Q: Can I get the vaccine if I am not feeling well?
A: If you are in a group that is currently eligible to receive the vaccine and you are not feeling well, it is recommended that you wait until you are feeling better to get the vaccine. If you have symptoms and/or signs of respiratory infection, evaluation and testing from health care resources in your community is recommended.
Q: What are the side effects of the vaccine?
A: Side effects in the phase 3 trials included flu-like symptoms such as aches, headache and fever. In the first few days of vaccination in the United Kingdom (where Pfizer’s vaccine was recently approved), two health care workers developed a severe allergic reaction (anaphylaxis) after receiving the vaccine, but both of these individuals had a prior history of severe allergic reactions. In response, British regulators have now advised patients with a history of severe allergic reactions to avoid getting the Pfizer vaccine until more is known about allergic reactions in severely allergic patients.
Q: If I had COVID-19 and recovered do I need to get the vaccine?
A: There is not enough information currently available to say if or for how long after infection someone is protected from getting COVID-19 again. Early evidence suggests natural immunity from COVID-19 is variable between individuals and may not last very long, but more studies are needed to better understand this area. Until we understand more about natural immunity to COVID-19, it is not known whether people who had COVID-19 will need to get a COVID-19 vaccine, although at least as of today it is recommended. That said, in Colorado, patients are advised that they can wait for up to ninety days after their infection before getting a vaccine, as re-infection is uncommon within the first three months following infection. Ultimately, if you recently had COVID-19 infection or have other concerns about receiving the vaccine, you should discuss your concerns and when and how to proceed with vaccination with your primary care physician.
Q: Does the COVID-19 vaccine take the place of the Pneumococcal vaccine or the flu vaccine?
A: No, the COVID-19 vaccine specifically protects against infection by SARS-CoV-2. It does not take the place of the pneumonia vaccine or the flu vaccine, which are caused by other organisms. Please consult with your health care provider regarding which vaccines are recommended for you.
Q: Is the COVID-19 vaccine safe for pregnant women? Breastfeeding women?
A: In early clinical trials for various COVID-19 vaccines, only non-pregnant adults participated. As of now, if you are pregnant or breastfeeding, it is recommended that you discuss the pros, cons, risks and benefits of vaccination as well as the timing of vaccination with your health care provider.
Q: Can children get the COVID-19 vaccine?
A: No. Children under 16 were not included in the early clinical trials for various COVID-19 vaccines. The groups recommended to receive the vaccines could change in the future, particularly as more clinical trials are completed. As of now, it is recommended that children under 16 do not receive the Pfizer vaccine and children under 18 do not receive the Moderna vaccine.
Q: Will the safety of the vaccine be monitored as it rolls out?
A: Yes. The CDC collects data to look for adverse events that are unexpected, appear to happen more often than expected, or have unusual patterns of occurrence. This data will continue to be gathered and analyzed.
Q: Can we stop masking and social distancing after receiving the vaccine?
A: No. You should continue to mask, practice social distancing and wash your hands often and well, even if you get a vaccine. These practices protect you and those around you. A vaccine does not immediately protect you. In addition, COVID-19 vaccines may protect against severe infection, but not necessarily prevent mild or asymptomatic infection. If this is the case, an infected person could still spread the virus, which can put others nearby at risk. Until we have a better idea of whether or not individuals who have been vaccinated can still spread the virus to others, and until a large percentage of the population has been fully vaccinated, you should still practice basic safety – mask-up, practice social distancing, wash your hands often and well. That said, we are clearly safer as individuals and as a community with vaccination than without.
Q: What is an Emergency Use Authorization (EUA)?
A: The FDA can issue an Emergency Use Authorization (EUA) during a public health emergency to allow the use of tested but unapproved medical products. They sometimes allow medical products and treatments that are approved for a certain use to be used in expanded or new ways. For the FDA to issue an EUA, safety and efficacy must be demonstrated, and certain criteria must be met, including that there are no adequate, approved and available alternatives.
Q: How much will a vaccine reduce the risk of COVID-19 and its complications?
A: The FDA guidance expects that an authorized or approved COVID-19 vaccine will prevent disease or decrease its severity in at least 50% of people who are vaccinated. Clinical trials of the Pfizer and Moderna vaccines indicated that those vaccines prevent or decrease the severity of the infection in about 95% of recipients. In some cases, COVID-19 vaccines may protect against severe infection, but not necessarily prevent mild or asymptomatic infection. If this is the case, an infected person could still spread the virus. This is why it is expected that even after a vaccine becomes available, people will need to continue wearing masks and practicing social distancing measures for some time.
Q: What are the phases for COVID-19 Vaccine Distribution?
Given the limited supply of vaccines in the first months of its availability, vaccines will be distributed in a phased process, with people at high risk of infection or severe disease inoculated first. The CDC has created a system to guide distribution of the vaccine. Each state has then fine-tuned these to the needs of their state. Here is the CDPHE guidance:
Q: When will a vaccine be available?
A: The Pfizer vaccine received EUA on Dec.11. The CDC and state guidelines recommend a phased rollout of the vaccine. Distribution of the first vaccines began on Monday, Dec. 14, with the first inoculations in Colorado occurring the same day. To ensure Colorado’s readiness to distribute the vaccine, CDPHE worked with hospitals, public health agencies, pharmacies and others to plan for COVID-19 vaccine distribution following the guidelines they set. Fully rolling out a vaccine to all who want it, will likely take several months, especially because supplies are limited at first. CDPHE is working to distribute the vaccine as equitably and efficiently as possible.
We anticipate that the model of vaccination is likely to change over time and be adapted to reflect the populations we need to serve.
Q: I had a known exposure in the last 14 days with a COVID-19 case, can I get the vaccine to stop me from developing the disease?
A: No. current evidence suggests that the vaccine cannot be used for post-exposure prophylaxis as protection from the vaccine is not immediate, requires 2 doses, and may take 1 to 2 weeks from second dose to acquired immunity.
If you have had a known exposure to COVID-19 you should not seek vaccination until the quarantine period has ended to avoid potentially exposing healthcare personnel and other during the vaccine visit and to make sure you are not sick with COVID-19 at the time of vaccination.
Q: I recently received passive antibody therapy for COVID-19, can I still get vaccinated with a COVID-19 vaccine?
A: Yes, BUT vaccination should be deferred for at least 90 days for individuals who had received monoclonal antibodies or convalescent plasma as part of COVID-19 treatment.
See Patient Vaccine Information for additional details.