Get answers to common and evolving questions around a COVID-19 vaccine
Two vaccines, manufactured by Pfizer-BioNTech and Moderna, are available under Emergency Use Authorization (EUA).
Distribution of vaccines that have been given emergency use authorization (EUA) has started and is on a state-by-state basis usually based on population. Actual distribution locally to hospitals, pharmacies and ultimately individuals is based on each states’ policy for distribution taking into account previous priorities that have been set—frontline workers, nursing home residents, essential workers, etc.
Initially, there will not be enough doses available for even the highest priority group of adults, which means not everyone will be able to get vaccinated right away. But supplies will increase over time, and all adults should be able to get vaccinated later in 2021, potentially the spring/summer timeframe. The goal is for anyone who wants to get vaccinated be able to do so once a COVID-19 vaccine is available.
Initially, there will not be enough doses available for all adults, which means certain groups will be prioritized to receive the vaccine first and not everyone would be able to get vaccinated right away. But supplies will increase over time, and all adults should be able to get vaccinated later in 2021. The goal is for anyone who wants to get vaccinated be able to do so once a COVID-19 vaccine is widely available. In the case of a limited supply, the CDC recommends vaccinating the following priority groups first.
- Healthcare personnel (doctors, nurses, respiratory therapists, dentists, pharmacists, environmental services staff, food services staff, and so forth in hospitals, physician offices, home health, nursing homes, rehabilitation centers, etc.)
- Residents of long-term care facilities
As more vaccine becomes available, additional priority groups will be eligible for vaccination, including:
- Persons aged 75+
- Frontline essential workers—this group includes individuals who work in essential jobs and are at a substantially higher risk of exposure to COVID-19 including those who work in the following fields: first responders, education, food & agriculture, manufacturing, public transit, etc.
- Persons aged 65-74
- Persons aged 16-64 with high-risk medical conditions
- Other essential workers—this group includes individuals who work in essential jobs such as: legal, IT & communication, media, construction, food service, finance, etc.
A COVID-19 vaccine may not be available for young children until more studies are completed.
Researchers are testing over 50 vaccines in clinical trials, and at least 90 preclinical vaccines are under active investigation. Currently, three types of vaccines are in phase 3 clinical trials or approaching phase 3. We don’t know if one is better than another, but they do work in different ways:
- Messenger RNA (mRNA) vaccines contain a copy of genetic information that looks like the SARS-CoV2 (the virus that causes COVID-19) virus’s information that causes COVID-19. This gives our cells instructions for how to make a harmless protein that is unique to the virus. After our cells make copies of the protein, our bodies recognize that the protein should not be there and build T-lymphocytes and B-lymphocytes and antibodies that will remember how to fight the virus that causes COVID-19 if we encounter the virus in the future. The Moderna and Pfizer vaccines are mRNA vaccines.
- Viral vector vaccines contain a modified, weakened virus (not the COVID-19 virus) that delivers a message for a protein like the spike protein of the SARS-CoV2 virus to be made by our cells. By instructing cells to make large amounts of antigen, which then triggers an immune response, the vaccine mimics what happens during natural infection with SARS-CoV2 and stimulates an immune response that will protect you from future encounters from the COVID-19 virus. The AstraZeneca and Johnson and Johnson vaccines are examples of these.
- Protein-based vaccines contain harmless coronavirus proteins, not the whole virus, and produces an immune response against the virus. The Novavax vaccine is an example of protein-based vaccines.
Different types of vaccines require different types of administrations. For some types of COVID-19 vaccines, the first shot would prime the immune system, helping it recognize the virus and the second shot would strengthen the immune response. Both the Pfizer and Moderna vaccines require two doses: 21 days apart for the Pfizer vaccine and 28 days apart for the Moderna vaccine. There isn’t information available on the need for booster shots—that would fall into long-term efficacy data which, we don’t have yet.
We only have preliminary data so far, based on phase 1 and 2 clinical trials, so it’s too early to fully report on side effects. In trials for the top vaccine candidates, Pfizer and Moderna, participants have said they experienced symptoms including fever, muscle aches, bad headaches and fatigue after receiving the shots, but the side effects generally did not last more than a day. Still, preliminary data suggests that, compared with most flu vaccines, the coronavirus shots have a somewhat higher rate of such reactions, which are almost always normal signs that the body’s immune response is kicking in.
The independent board that conducted the interim analysis of Moderna’s large trial found that severe side effects included fatigue in 9.7% of participants, muscle pain in 8.9%, joint pain in 5.2% and headache in 4.5%. For the Pfizer vaccine, the numbers were lower: Severe side effects included fatigue (3.8%) and headache (2%).
A key reason to get vaccinated is to protect against having severe complications up to and including death, especially among those who are in the high-risk group.
So, although it is important to be aware of safety and side effect issues around the vaccine, each person should weigh these usually mild side effects of arm soreness and fatigue for a day or two against the great benefit of protecting against moderate to severe illness which can occur at any age and in people without any underlying conditions.
In clinical trials both vaccines have shown approximately 95% efficacy, which is very promising. This means that in the clinical trials, the vaccine prevented 95% of the clinical cases compared to the placebo group recipients. However, it’s important to note that we don’t know what will happen in the “real world” until people start being vaccinated.
No. Like the flu shot and other vaccines, COVID-19 vaccines cannot give you the virus.
If you had COVID-19 and recovered from it, you probably have some antibodies, but it is still unknown as to how long that protection against reinfection will last. Some early evidence suggests natural immunity may not last very long.
This is It is currently unknown. When we know how long immunity from the vaccine will last, decisions can be made about timing of re-vaccination.
No, the vaccines are approved because they are deemed safe, regardless of the shortened timeframe. The U.S. Food and Drug Administration’s (FDA’s) Center for Biologics Evaluation and Research is responsible for regulating vaccines in the United States. And each vaccine producer must follow a multi-step approval process that includes sharing research from clinical trials.
FDA can also require a manufacturer to submit the results of their own tests for potency, safety, and purity for each vaccine lot. Vaccines typically require years of research and testing before reaching the public, but scientists are racing to produce a safe and effective coronavirus vaccine more quickly. This doesn’t mean that the vaccine is less safe, it just means that the whole world is keen to ensure that we are protected from this new threat to lung health and so researchers have been working collaboratively to build a knowledge base of what works and achieved success quickly.
After approving a vaccine, FDA continues to oversee its production to ensure continuing safety. Monitoring of the vaccine and of production activities, including periodic facility inspections, must continue as long as the manufacturer holds a license for the vaccine product.
V-safe is a smartphone-based tool that uses text messaging and web surveys to provide personalized health check-ins after you receive a COVID-19 vaccination. Through v-safe, you can quickly tell CDC if you have any side effects after getting the COVID-19 vaccine. Depending on your answers, someone from CDC may call to check on you. And v-safe will remind you to get your second COVID-19 vaccine dose if you need one.
In addition, the Vaccine Adverse Event Reporting System (VAERS) is a national vaccine safety surveillance program that collects and analyzes side effects that occur. Reports from patients, providers, pharmacists and vaccine manufacturers can all be submitted to VAERS.
It depends. Immunity is when the body can resist a particular disease, and vaccines help build up that immunity by stimulating antibody production and immune cells (T and B lymphoctyes) for future protection. Immunity works best at the community level so when enough people are vaccinated then an infected individual has nobody to spread the disease to. A vaccination can help prevent getting the infection or at least keeping the severity of the infection to a mild level. Everyone’s immune system responds a little differently.
The government’s public-private partnership, Operation Warp Speed, has a goal to produce and deliver 300 million doses of safe and effective vaccines with the initial doses available by January 2021, as part of a broader strategy to accelerate the development, manufacturing, and distribution of COVID-19 vaccines, therapeutics and diagnostics.
Yes! The vaccine will not replace the basic safety measures of wearing masks, social distancing and handwashing, especially as a vaccine will very likely not be available during what most experts agree will be a tough winter.
Even when a vaccine is widely available, additional measures like masks will still be necessary until the public health threat has subsided. It is an important safety measure not only for yourself but for those around you.
Having seasonal or food allergies does not mean you will experience a reaction to the vaccine. If you have a history of severe allergic reactions you should talk to your physician before receiving an mRNA COVID-19 vaccination. They will help you determine if you have experienced a severe allergic reaction (e.g., anaphylaxis) to any component of a COVID-19 vaccine listed in the prescribing information, in which case the vaccine would not be recommended. Established COVID-19 vaccination protocols suggest all persons be observed after vaccination for a minimum of 15 minutes.
The American Lung Association urges members of the public to always consult with their own healthcare providers about whether this or any vaccine is appropriate for them.
Page last updated: January 14, 2021