Vaccine FAQs

Yes, there are currently three vaccines approved by the U.S. Food and Drug Administration (FDA) to prevent COVID-19 – Pfizer-BioNTech, Moderna and Johnson & Johnson (J&J). These vaccines were approved under the FDA’s Emergency Use Authorization (EUA) process, which allows safe and effective medicines to be deployed on an accelerated schedule during a public health emergency such as the current COVID-19 pandemic. The Pfizer vaccine is approved for people over 16 years of age, while the Moderna and J&J vaccines are approved for those over age 18. Additional vaccines are in clinical trials and may be approved later. 

By all accounts, the vaccines are safe and effective, and the benefits of getting vaccinated far outweigh the risks. All three approved vaccines have significantly reduced death and illness requiring hospitalization. The vaccines are also demonstrated to be safe by the high standards set for vaccines. Vaccines approved under the EUA process are evaluated by an independent panel of experts under rigorous FDA standards for safety and effectiveness. FDA reviewed two months’ worth of safety data in granting the EUAs, which is the period in which safety issues typically would surface. Roughly 75,000 individuals have taken part in clinical trials for the five major vaccine candidates, and more than 347 million doses have been administered in the U.S. Serious side effects are extremely rare. 

People taking the vaccine have reported mostly mild, temporary side effects, such as pain where they were injected, fatigue, and occasional fever, headache or aches in muscles and joints. When they occur, these side effects typically fade within a couple of days. Participants report that the side effects are more pronounced after the second injection. These are common side effects with all vaccines and indicate that the body’s immune system is developing protections from the virus.

In rare cases, individuals with severe allergies have experienced severe allergic reactions to the vaccine. Those individuals were treated and have recovered. Vaccine administration protocols call for recipients to be observed after the injection and to be treated for an allergic reaction if it occurs. Health experts recommend that people who report allergies unrelated to vaccines be given a skin allergy test before receiving the vaccine, and people who have severe allergies to vaccines, medicines or food should not get a vaccine at this time.

The FDA has added a warning label to the Johnson & Johnson vaccine about a rare neurological side effect called Guillain-Barré syndrome. About 100 cases of the disease have been reported out of approximately 12.8 million J&J vaccines administered to date. Previously, the J&J vaccine was temporarily paused to investigate reports of a rare but serious blood clot disorder. It’s important to note that the risk of serious side effects after any COVID-19 vaccination is very rare, and far lower than adverse outcomes of the disease itself. The risk of developing blood clots, for example, is much higher among people who contract COVID-19 than among J&J vaccine recipients.

Public health experts encourage you to get the first vaccine available to you. There is a misperception among some that the Johnson & Johnson vaccine is not as good as the Pfizer or Moderna shots. In fact, the J&J vaccine proved highly effective in trials, eliminating deaths from COVID-19 and eliminating cases requiring hospitalization. And J&J is a one-shot vaccine, eliminating the need to schedule a second shot weeks later as with the Pfizer and Moderna vaccines. FDA has explained that it’s not possible to make comparisons about the effectiveness of the various vaccines because the shots were not tested in head-to-head clinical trials. The J&J vaccine was tested in different locations and at different times than the other shots, and was tested against emerging virus variants that are more transmissible. 

Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, said of the J&J shot, “It’s not the weaker vaccine,” adding, "all three of them are really quite good, and people should take the one that's most available to them…. If you go to a place and you have J&J and that's the one that's available now, I would take it. I personally would do the same thing. I think people need to get vaccinated as quickly and as expeditiously as possible." 

The delta variant is a naturally occurring mutation of the coronavirus that is more infectious and spreads more easily than the original COVID-19 virus. Lab tests suggest that the delta variant infects people with a heavier virus load, up to 1,000 times more than the original virus, which means they exhale more of it for others to catch. People infected with the delta variant are also more likely to need hospitalization than those infected with earlier strains of the virus. The delta variant accounts for more than 80% of new COVID-19 cases in the U.S.

Yes. The COVID-19 vaccines are extremely effective in protecting fully vaccinated people from catching and spreading the virus, including the delta variant. But it is critical that you are fully vaccinated to be protected. The vaccines are slightly less effective at preventing COVID-19 from the delta variant, but they remain highly effective at preventing serious illness, hospitalization and death. A New England Journal of Medicine study published in July found that the Pfizer vaccine is 88% effective at preventing symptomatic disease from the delta variant.

Since no vaccine is 100% effective at preventing illness, there will be a small percentage of fully vaccinated people who still get sick, are hospitalized, or die from COVID-19. Dr. Fauci has explained that breakthrough cases among fully vaccinated people are inevitable but stressed that more than 99% of those who died from COVID-19 in June were not vaccinated.

Yes, the vaccines were tested on diverse populations and found to be safe and effective. Many African Americans are justifiably wary of the medical establishment, because of a historic legacy of racism in health care, including carrying out unethical medical experiments on African Americans, stealing their biological property for profit and disregarding their health needs. Still, it is especially critical that African Americans, Latinos and Native Americans receive the vaccine because many work in jobs that put them at additional risk to contract the virus and because these groups are at greater risk of death and serious illness from the disease.

No. It is impossible to get COVID-19 from any of the vaccines since they do not contain any live virus. Instead, they instruct your body to recognize the signature “spike proteins” of the coronavirus, helping your immune system to fight the virus that causes COVID-19 if you are infected. It’s important to remember, however, that it takes two weeks after the shot for your body to produce full immunity, and it’s possible to become infected during that time.

Public health experts recommend that people who have had COVID-19 should still get a vaccine, because it is uncertain how long people retain natural immunity after recovering from the illness. Experts advise waiting 90 days after their diagnosis before getting the shot. Vaccine trials of participants who have recovered from COVID-19 show that the vaccine is safe in those who were previously infected.

Based on increased transmission from the delta variant, CDC now recommends that fully vaccinated people:

• Should wear masks in indoor public places in areas of high or substantial community transmission. This means counties with 50 or more cases per 100,000 population in the last seven days, or with an 8% or higher positivity rate on COVID-19 tests. As of today, 2,043 counties out of a total of 3,219 are classified as substantial or high. These counties are concentrated in the South, lower Midwest and Mountain West. Fully vaccinated people may choose to wear a mask regardless of the level of community transmission, especially if they or someone in their household has a compromised immune system or is at increased risk of severe disease.
• May still go without masks outdoors. Fully vaccinated people may choose to wear masks in crowded outdoor settings if they or someone in their household has a compromised immune system or is at increased risk of severe disease.
• Should wear masks indoors in schools, including all school employees, students and visitors.
• Should wear a mask in public indoor settings for up to 14 days or until they receive a negative test after a known exposure to someone with COVID-19. The person should get tested three to five days after exposure.

CDC continuously reviews the scientific data to update recommended public health measures. People should continue to follow public health directives issued by state and local authorities. Officials regularly revise these directives based on CDC guidance as well as rates of infection in each community.

Wearing masks remains one of the most effective measures that people can take to protect themselves from infection and slowing the spread of COVID-19. Local and state officials establish policies based on local scenarios, including vaccination and transmission rates. Where there are lower vaccination rates and higher infection rates, or where disparities persist across population groups, officials may reinstate masking policies — such as indoor masking — with the goal of slowing transmission of the virus and protecting people who are not or cannot be vaccinated.

Most legal analysts agree that employers can require their employees to take the vaccine. Employees working under union contracts can bargain over impacts of a mandate, and AFSCME encourages union members to demand bargaining to ensure they are treated fairly. Workers with disabilities or health conditions may request exemptions under the Americans with Disabilities Act, and employees with religious objections have the right to refuse vaccines and will be protected by the EEOC. These rights are limited, however, if the employer can show that a worker’s refusal to be vaccinated would cause an undue burden or pose a direct threat to the workplace. At the state level, lawmakers in 45 states proposed barring or limiting employers from mandating vaccines among their workforces, and measures were signed into law in seven states so far.