COVID-19 vaccines: Get the facts
Looking to get the facts about the new COVID-19 vaccines? Here's what you need to know about the different vaccines and the benefits of getting vaccinated.
Vaccines to prevent coronavirus disease 2019 (COVID-19) are perhaps the best hope for ending the pandemic. But as the U.S. Food and Drug Administration (FDA) continues approving or authorizing emergency use of COVID-19 vaccines, you likely have questions. Find out about the benefits of the COVID-19 vaccines, how they work, the possible side effects and the importance of continuing to take infection prevention steps.
COVID-19 vaccine benefits
What are the benefits of getting a COVID-19 vaccine?
A COVID-19 vaccine might:
· Prevent you from getting COVID-19 or from becoming seriously ill or dying due to COVID-19
· Prevent you from spreading the virus that causes COVID-19 to others
· Add to the number of people in the community who are protected from getting COVID-19 — making it harder for the disease to spread and contributing to herd immunity
· Prevent the virus that causes COVID-19 from spreading and replicating, which allows it to mutate and possibly become more resistant to vaccines
Should I get the COVID-19 vaccine even if I've already had COVID-19?
Getting COVID-19 offers some natural protection or immunity from reinfection with the virus that causes COVID-19. It's estimated that infection with the virus that causes COVID-19 and vaccination both result in a low risk of another infection with a similar variant for at least 6 months.
But because reinfection is possible and COVID-19 can cause severe medical complications, it's recommended that people who have already had COVID-19 get a COVID-19 vaccine.
In addition, COVID-19 vaccination might offer better protection than getting sick with COVID-19. A recent study showed that unvaccinated people who already had COVID-19 are more than twice as likely as fully vaccinated people to be reinfected with COVID-19.
Recent research also suggests that people who got COVID-19 in 2020 and then received mRNA vaccines produce very high levels of antibodies that are likely effective against current and, possibly, future variants. Some scientists call this hybrid immunity. Further research is needed.
If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, wait 90 days before getting a COVID-19 vaccine.
Can a COVID-19 vaccine give you COVID-19?
No. The COVID-19 vaccines currently being developed in the U.S. don't use the live virus that causes COVID-19. As a result, the COVID-19 vaccines can't cause you to become sick with COVID-19 or shed any vaccine components.
Keep in mind that it will take a few weeks for your body to build immunity after getting a COVID-19 vaccination. As a result, it's possible that you could become infected with the virus that causes COVID-19 just before or after being vaccinated.
What are the possible general side effects of a COVID-19 vaccine?
A COVID-19 vaccine can cause mild side effects after the first or second dose, including:
· Pain, redness or swelling where the shot was given
· Muscle pain
· Joint pain
· Nausea and vomiting
· Feeling unwell
· Swollen lymph nodes
You'll be monitored for 15 minutes after getting a COVID-19 vaccine to see if you have an allergic reaction. Most side effects go away in a few days. Side effects after the second dose might be more intense. Many people have no side effects.
A COVID-19 vaccine may cause side effects similar to signs and symptoms of COVID-19. If you've been exposed to COVID-19 and you develop symptoms more than three days after getting vaccinated or the symptoms last more than two days, self-isolate and get tested.
What are the long-term side effects of the COVID-19 vaccines?
Because COVID-19 vaccines clinical trials only started in the summer of 2020, it’s not yet clear if these vaccines will have long-term side effects. However, vaccines rarely cause long-term side effects.
If you're concerned, in the U.S., safety data on COVID-19 vaccines will be reported to a national program called the Vaccine Adverse Event Reporting System. This data is available to the public. The CDC has also created v-safe, a smartphone-based tool that allows users to report COVID-19 vaccine side effects.
If you have additional questions or concerns about your symptoms, talk to your doctor.
Can COVID-19 vaccines affect the heart?
In the U.S., there has been an increase in reported cases of myocarditis and pericarditis after mRNA COVID-19 vaccination, particularly in males ages 12 through 17. Myocarditis is the inflammation of the heart muscle, while pericarditis is the inflammation of the lining outside the heart. These reports are rare. One study suggests that the risk of myocarditis in the week after being fully vaccinated with the Pfizer-BioNTech vaccine is about 54 cases per million doses given to males ages 12 to 17.
Of the cases reported, the problem happened more often after the second dose of the COVID-19 vaccine and typically within several days after COVID-19 vaccination. Most of the people who received care felt better after receiving medicine and resting. Symptoms to watch for include:
· Chest pain
· Shortness of breath
· Feelings of having a fast-beating, fluttering or pounding heart
If you or your child has any of these symptoms within a week of getting a COVID-19 vaccine, seek medical care.
What are the symptoms of a blood clotting reaction to the Janssen/Johnson & Johnson COVID-19 vaccine?
Use of the Janssen/Johnson & Johnson COVID-19 vaccine might increase the risk of a rare and serious blood clotting disorder. Nearly all of those affected have been women ages 18 to 49, with the disorder happening at a rate of 7 for every 1 million vaccinated women in this age group. For women age 50 and older and men of all ages, the disorder is even more rare.
The FDA and the CDC have recommended that use of the vaccine in the U.S. can continue because the benefits outweigh the risks. (36) Evidence of these blood clots haven’t been reported in the Pfizer-BioNTech or Moderna COVID-19 vaccines.
Serious side effects of the Janssen/Johnson & Johnson COVID-19 vaccine can occur within three weeks of vaccination and require emergency care. Possible symptoms include:
· Shortness of breath
· Persistent stomach pain
· Severe or persistent headaches or blurred vision
· Chest pain
· Leg swelling
· Easy bruising or tiny red spots on the skin beyond the injection site
Mild to moderate headaches and muscle aches are common in the first three days after vaccination and don't require emergency care.
Variants and COVID-19 vaccines
Do the COVID-19 vaccines protect against the COVID-19 variants?
In the U.S., the delta (B.1.617.2) variant is now the most common COVID-19 variant. It is nearly twice as contagious as earlier variants and might cause more severe illness.
While research suggests that COVID-19 vaccines are slightly less effective against the variants, the vaccines still appear to provide protection against severe COVID-19. For example:
· Early research from the U.K. suggests that, after full vaccination, the Pfizer-BioNTech COVID-19 vaccine is 88% effective at preventing symptomatic COVID-19. The vaccine is also 96% effective at preventing severe disease with COVID-19 caused by the delta variant.
· Early research from Canada suggests that, after one dose, the Moderna COVID-19 vaccine is 72% effective at preventing symptomatic COVID-19 caused by the delta variant. One dose of the vaccine is also 96% effective at preventing severe disease with COVID-19 caused by the delta variant.
· The Janssen/Johnson & Johnson COVID-19 vaccine is 85% effective at preventing severe disease with COVID-19 caused by the delta variant, according to data released by Johnson & Johnson.
Can I get a COVID-19 vaccine if I have an existing health condition?
Yes, if you have an existing health condition you can get a COVID-19 vaccine — as long as you haven't had an allergic reaction to a first dose of a COVID-19 vaccine or any of its ingredients. But there is limited information about the safety of the COVID-19 vaccines in people who have weakened immune systems or autoimmune conditions.
COVID-19 vaccines also might not fully protect people from COVID-19 who have a weakened immune system that is caused by HIV, certain conditions or medications. It might be necessary to continue taking precautions.
Is it OK to take an over-the-counter pain medication before or after getting a COVID-19 vaccine?
It isn’t recommended that you take an over-the-counter medication before getting a COVID-19 vaccine to prevent possible discomfort. It’s not clear how these medications might impact the effectiveness of the vaccines. However, it’s OK to take this kind of medication after getting a COVID-19 vaccine, as long as you have no other medical reason that would prevent you from taking it.
Is there anyone who should not get a COVID-19 vaccine?
There is no COVID-19 vaccine yet for children under age 5. Clinical trials involving younger children are in progress.
Allergic reactions and COVID-19 vaccines
What are the signs of an allergic reaction to a COVID-19 vaccine?
You might be having an allergic reaction to a COVID-19 vaccine if you experience these signs within four hours of getting vaccinated:
· Swelling of the lips, eyes or tongue
If you have any signs of an allergic reaction, get help right away. Tell your doctor about your reaction, even if it went away on its own or you didn’t get emergency care. This reaction might mean you are allergic to the vaccine. You might not be able to get a second dose of the same vaccine. However, you might be able to get a different vaccine for your second dose.
Can I get a COVID-19 vaccine if I have a history of allergic reactions?
If you have a history of severe allergic reactions not related to vaccines or injectable medications, you may still get a COVID-19 vaccine. You should be monitored for 30 minutes after getting the vaccine.
If you've had an immediate allergic reaction to other vaccines or injectable medications, ask your doctor if you should get a COVID-19 vaccine. If you’ve ever had an immediate or severe allergic reaction to any ingredient in a COVID-19 vaccine, the CDC recommends not getting that specific vaccine.
If you have an immediate or severe allergic reaction after getting the first dose of a COVID-19 vaccine, don't get the second dose. However, you might be able to get a different vaccine for your second dose.
Can pregnant or breastfeeding women get the COVID-19 vaccine?
If you are pregnant or breastfeeding, it's recommended that you get a COVID-19 vaccine. Getting a COVID-19 vaccine can protect you from severe illness due to COVID-19. Vaccination can also help pregnant women build antibodies that might protect their babies.
COVID-19 vaccines don't cause infection with the virus that causes COVID-19, including in pregnant women or their babies. None of the COVID-19 vaccines contain the live virus that causes COVID-19.
While further research is needed, early findings suggests that getting an mRNA COVID-19 vaccine during pregnancy poses no serious risks for pregnant women who were vaccinated or their babies. The findings are based on data from the CDC’s coronavirus vaccine safety monitoring system. Also, keep in mind that mRNA COVID-19 vaccines don't alter your DNA.
In addition, vaccines that use the same viral vector as the Janssen/Johnson & Johnson COVID-19 vaccine have been given to pregnant women in each trimester of pregnancy in clinical trials. No harmful effects were found.
If you have concerns, talk to your health care provider about the risks and benefits of getting a COVID-19 vaccine.
Can a COVID-19 vaccine affect fertility or menstruation?
It's recommended that you get a COVID-19 vaccine if you are trying to get pregnant or might become pregnant in the future. There is no evidence that any COVID-19 vaccines cause fertility problems.
A small number of women have reported experiencing temporary menstrual changes after getting a COVID-19 vaccine. A small study has also shown that some women experienced temporary menstrual changes after getting COVID-19. It's not clear if getting COVID-19 or a COVID-19 vaccine causes these changes. Further research is needed.
Keep in mind that many things can affect menstrual cycles, including infections, stress, sleep problems and changes in diet or exercise.
If you become pregnant after getting the first dose of a COVID-19 vaccine that requires two doses, it’s recommended that you get your second shot.
If children don’t frequently experience severe illness with COVID-19, why do they need a COVID-19 vaccine?
A COVID-19 vaccine can prevent your child from getting and spreading the virus that causes COVID-19.
If your child gets COVID-19, a COVID-19 vaccine could prevent him or her from becoming severely ill or experiencing short-term or long-term complications. Children with other health conditions, such as obesity, diabetes and asthma, might be at higher risk of serious illness with COVID-19.
Getting a COVID-19 vaccine can also help keep your child in school and more safely have playdates and participate in sports and other group activities.
Can I stop taking safety precautions after getting a COVID-19 vaccine?
You are considered fully vaccinated 2 weeks after you get a second dose of an mRNA COVID-19 vaccine or 2 weeks after you get a single dose of the Janssen/Johnson & Johnson COVID-19 vaccine. Currently, there is no time limit after vaccination on your fully vaccinated status.
After you are fully vaccinated, you can more safely return to doing activities that you might not have been able to do because of the pandemic. You can also stop wearing a mask or social distancing in any setting, except where required by a rule or law. However, if you are in an area with a high number of new COVID-19 cases in the last week, the CDC recommends wearing a mask indoors in public and outdoors in crowded areas or when you are in close contact with unvaccinated people. If you are fully vaccinated and have a condition or are taking medications that weaken your immune system, you may need to keep wearing a mask.
You also will still be required to wear a mask on planes, buses, trains and other public transportation traveling to, within, or out of the U.S., as well as in places such as airports and train stations.
If you are traveling in the U.S., you don’t need to get tested before or after your trip or quarantine after you return. If you are traveling outside of the U.S., you don’t need to get tested before you leave the U.S. unless your destination requires it. You still need to show a negative test result or proof that you’ve recovered from COVID-19 in the past 3 months before boarding an international flight to the U.S. It’s also recommended that you get tested 3 to 5 days after international travel. However, quarantining isn't needed.
If you’ve been fully vaccinated and you’ve had close contact with someone who has the COVID-19 virus, get tested 5 to 7 days afterward. And if you are a resident or employee of a correctional or detention facility or a homeless shelter and are around someone who has COVID-19, you should still get tested even if you don’t have symptoms of COVID-19.
Can I still get COVID-19 after I’m vaccinated?
A small percentage of fully vaccinated people will still get COVID-19 if they are exposed to the virus that causes COVID-19. These are called vaccine breakthrough infections.
People with vaccine breakthrough infections may spread COVID-19 to others. However, it appears that vaccinated people spread COVID-19 for a shorter period than do unvaccinated people.
Vaccination also might make illness less severe. If you are fully vaccinated, the overall risk of hospitalization and death due to COVID-19 is much lower than among unvaccinated people with similar risk factors.
Are COVID-19 vaccine additional doses or boosters recommended?
An additional dose of a COVID-19 vaccine is recommended for people who are fully vaccinated and might not have had a strong enough immune response. In contrast, a booster dose is recommended for some people who are fully vaccinated and whose immune response weakened over time.
The CDC recommends additional doses and booster doses of COVID-19 vaccines in specific instances:
· Additional dose. The CDC recommends a third dose of an mRNA COVID-19 vaccine for some people with weakened immune systems, such as those who have had an organ transplant. People with weakened immune systems might not develop enough immunity after vaccination with two doses of an mRNA COVID-19 vaccine. An additional dose might improve their protection against COVID-19.
The third dose should be given at least 28 days after a second dose of an mRNA COVID-19 vaccine. The additional dose should be the same brand as the other two mRNA COVID-19 vaccine doses you were given. If the brand given isn’t known, either brand of mRNA COVID-19 vaccine can be given as a third dose.
· Booster dose. If you have been given both doses of the Pfizer-BioNTech COVID-19 vaccine or the Moderna COVID-19 vaccine and it’s been at least 6 months, you might be able to get a booster dose. The CDC recommends a booster dose for people age 65 and older and for people age 18 and older who live in long-term care settings, have an underlying medical condition, or live or work in a high-risk setting. Pregnant women can also get a COVID-19 booster shot.
If you have been given one dose of the Janssen/Johnson & Johnson COVID-19 vaccine and it’s been at least 2 months, you also might be able to get a booster dose. The CDC recommends a booster dose for people age 18 and older.
You may choose which vaccine you get as a booster dose. You can get a booster dose that is the same brand as your previous shot or shots or choose a different brand.