Updated March 1, 2021
The only safe way to end the pandemic is for the majority of people to get vaccinated.
The Covid-19 pandemic will continue to spread until the majority of the population is immune to the virus, also known as herd immunity. When herd immunity is achieved, those who are immune to a virus are effectively protecting people around them who are not able to achieve immunity. Herd immunity in the U.S. is projected to be achieved when at least 70% of the population (approximately 225 million people) has been vaccinated.
Pfizer vaccine trial:
Moderna’s vaccine trial showed similar results.
In clinical trials, the Johnson & Johnson vaccine proved to be safe and effective against COVID-19. We encourage people to get whichever vaccine is offered. It’s most important that you get vaccinated. Vaccine efficacy looks at how well the vaccine prevents any type of illness. However, we ultimately measure the effectiveness of the vaccines by how well they do at preventing severe illness, hospitalizations and death. All three of the approved vaccines have proven to be very effective by that measure.
The Johnson & Johnson vaccine uses a different mechanism than the Pfizer and Moderna vaccines and requires one dose rather than two. It comes out of decades of research on adenovirus-based vaccines. This type of vaccine uses a modified adenovirus that can enter cells but can’t replicate inside them or cause illness. It proved to be safe in clinical trials and was approved by a panel of physicians, public-health officials and infectious-disease specialists. The same rigorous approval process was used for the Johnson & Johnson, Pfizer and Moderna vaccines.
Vaccines will initially be given to people 16 and older. Trials are currently underway for pregnant people and children ages 12-17. Eventually there will be trials for children under 12 and specific immunosuppressed groups.
Yes. It’s important to get vaccinated even if you have previously had Covid-19.
The Pfizer and Moderna vaccines have been proven to be effective in protecting against Covid-19 infection.
No. While highly effective the vaccine is not 100% protective. Vaccinated persons may still get infected, and it is unknown whether vaccinated persons can become asymptomatically infected and shed virus that could infect other people. It is also not yet known whether booster vaccines will be needed to in order to continue having protection against Covid-19, nor how often those booster vaccines would be needed.
It is important to keep wearing masks and distancing even after you have been vaccinated, to help protect those who have not yet been vaccinated and to continue to protect yourself.
Yes, the vaccine is safe based on the clinical trial and expert review.
No steps were eliminated or skipped in vaccine development and testing and all usual safety protocols for new vaccines were followed.
Vaccine approval process:
The approval process included the review of physicians and scientists, including a special FDA advisory board on vaccines and an independent panel of scientists representing California, Nevada Oregon and Washington.
Vaccine development timeframe:
While the vaccines were developed in a shorter timeframe than usual, evidence shows that these two vaccines are safe. Scientists and researchers were able to develop the vaccines more quickly than other vaccines because:
If any concerning results or side effects occur during any drug trial, it is paused – this did not happen for either the Pfizer or the Moderna vaccine.
Vaccines to prevent infectious diseases are given safely to millions of babies, children, adolescents and adults every year. Vaccines have prevented countless cases of disease and disability and have saved millions of lives.
Decades of work and research into genetic vaccines (mRNA), which is the process used to develop the Pfizer and Moderna vaccines, led to their development.The mRNA vaccines are highly effective and safe across groups and ages. mRNA, which is what was used to develop the Pfizer and Moderna vaccines, does not incorporate into our DNA and degrades naturally after a few days.
We encourage you to get vaccinated when it is your turn and you are offered any of the approved vaccines. All three of the approved vaccines have proven to be very effective at preventing severe illness, hospitalizations and death. It’s important to weigh the benefits of getting the vaccine versus the risks of getting COVID-19.
We won't be able to stop the pandemic and return to normal life until all of us get vaccinated, including young healthy people. We all have to do our part to stop the chain of infection from one person to another. And while it’s possible you won’t get very sick, you never know how your body might react to the disease. You could also pass it along to your family members and friends who could be more at risk of serious infection. Please get vaccinated when it’s your turn.
According to the American College of Obstetricians and Gynecologists (ACOG), it's not necessary to delay getting pregnant after receiving the COVID-19 vaccine. If you find out that you're pregnant after the first dose, it's recommended that you still get the second dose. Read the ACOG's full advisory here and talk to your doctor about what may be best for your situation.
The American College of Obstetricians and Gynecologists (ACOG) has recommended that the vaccine be made available to pregnant and lactating women, as they believe it's safe. Read the ACOG's full advisory here and talk to your doctor about what may be best for your situation.
Given the safety profile of the mRNA Covid-19 vaccines, it's not thought or expected that the vaccine would decrease your fertility in any way. Read the ACOG's full advisory here and talk to your doctor about what may be best for your situation.
The Centers for Disease Control and Prevention (CDC) advise that mRNA COVID-19 vaccines may be administered to people with underlying medical conditions provided they have not had a severe or immediate allergic reaction to any of the ingredients in the vaccine.
For more information, please see the CDC website.
Neither of the two currently approved COVID-19 vaccines contain animal products. For a full list of ingredients, see: