Questions & Answers About the Vaccine The following FAQs are available in more detail at getvaccineanswers.org. FAQs What should I expect after getting a COVID-19 vaccine? How do the COVID-19 vaccines protect me? How do we know COVID-19 vaccines are safe? What are the benefits of getting vaccinated for COVID-19? Is the vaccine safe for my child? What are the benefits of vaccination for children? Should I worry about long-term side effects? Do vaccines impact fertility? Could I have an allergic reaction? Should I get a vaccine if I have had COVID-19? What should I know about vaccines and Guillain-Barré Syndrome? Will I need a COVID-19 booster shot? What should I expect after getting a COVID-19 vaccine? You may have short-term side effects after vaccination. These are normal and should go away in a few days.You may feel soreness or experience some swelling in your arm. You may also feel tired, have a headache, fever, or chills. These symptoms do not mean you have COVID-19 — it’s not possible to get COVID-19 from the vaccine.These side effects may impact your daily activities, but they shouldn’t last more than 2-3 days. If they continue or get worse, call your doctor, nurse, or clinic.Even if you have these types of effects after your first shot, it’s important to make sure you get the second one, unless a vaccination provider or your doctor tells you not to get a second shot or you get the single dose vaccine. Ask your doctor if you have questions. Your body takes time to build immunity. You will not be fully protected against COVID-19 until 1-2 weeks after your final shot in your initial series or your booster shot.In most cases, discomfort from fever or pain is normal. Contact your doctor or healthcare provider:If the redness or tenderness where you got the shot increases after 24 hoursIf your side effects are worrying you or do not seem to be going away after a few daysIf you develop severe headache, abdominal pain, leg pain, or shortness of breath within the first three weeks.If you get a COVID-19 vaccine and you think you might be having a severe allergic reaction after leaving the vaccination site, seek immediate medical care by calling 911. Learn more about COVID-19 vaccines and rare severe allergic reactions. How do the COVID-19 vaccines protect me? COVID-19 vaccines are a critical tool to bring the pandemic under control. The risk of severe disease and death are all much lower for people who are vaccinated, compared to unvaccinated people. All authorized COVID-19 vaccines provide strong protection against serious illness and hospitalization due to COVID-19.When we get a vaccine, it activates our immune response. This helps our bodies learn to fight off the virus without the danger of an actual infection. If we are exposed to the virus in the future, our immune system “remembers” how to fight it.The Moderna and Pfizer-BioNTech vaccines use messenger RNA, or mRNA. mRNA vaccines do not contain a live virus. They give our bodies “instructions” for how to make and fight the spike-shaped proteins that will protect against a COVID-19 infection. While these vaccines use new technology, researchers have been studying them for decades.Johnson & Johnson’s Janssen vaccine is a viral vector vaccine and does not contain a live virus either. It uses a harmless adenovirus to create a spike protein that the immune system responds to, creating antibodies to protect against COVID-19.None of these vaccines can give you COVID-19.It takes time for your body to build immunity after vaccination, so you won’t have full protection until 2 weeks after your most recent dose. How do we know COVID-19 vaccines are safe? More than 240 million people in the United States, including 96% of medical doctors, have now received one dose of a COVID-19 vaccine. These vaccines have been through the most intensive safety monitoring in U.S. history.Vaccines are approved and authorized by the U.S. Food and Drug Administration (FDA). The FDA sets strict standards for clinical trials and carefully reviews scientific data from vaccine developers. Once vaccines are made available to the public, the FDA continues to monitor them very closely.Researchers began developing vaccines for COVID-19 in January 2020, based on decades of work on immune responses and vaccine technology. Thousands of volunteers took part in the clinical trials that started that spring to ensure the vaccines are safe and effective.Based on the results, the FDA authorized multiple vaccines for public use. In August 2021, the Pfizer vaccine (Comirnaty) was approved by the FDA.Doctors and medical experts with many years of experience regulating vaccines looked at information about the safety, effectiveness, and quality of the vaccines before making their decision. What are the benefits of getting vaccinated for COVID-19? Being up to date with COVID-19 vaccines drastically reduces the likelihood that you will get seriously ill from COVID-19. If you do get infected, vaccines also greatly reduce the chances of dying from the disease. And, if you're vaccinated and do get COVID-19, recent data suggests that you would spread the virus for a shorter time.Most side effects from the vaccine are mild (redness or swelling of the injection site) and go away within a few days.Protecting yourself protects those around you, such as people at increased risk of severe illness from COVID-19. It also helps protect those who can’t get vaccinated, including infants, or people with immune systems weakened by things like chemotherapy for cancer. Is the vaccine safe for my child? Studies show that COVID-19 vaccines are safe and effective for children age 5 and up. The COVID-19 vaccines program is being watched more closely than any other public health effort in U.S. history. Clinical trials included thousands of children in these age groups. They found the authorized vaccines to be very safe and effective. Nearly 5 million kids have already received at least one dose since vaccines were authorized for ages 5 to 11.Like adults, children and teens might have some side effects after getting a COVID-19 vaccine. These include site injection pain, headache, fever and muscle ache. These side effects might affect your child or teen's ability to do daily activities, but they should go away within a few days.The CDC, the American Academy of Pediatrics (AAP), and the National Association of Pediatric Nurse Practitioners recommend children age 5 and older should get COVID-19 vaccines as soon as they can. If you have questions or concerns, talk to a pediatrician or healthcare professional. What are the benefits of vaccination for children? As of December 2021, nearly 7.2 million children have tested positive for COVID-19 since the onset of the pandemic. COVID cases among children have been higher in recent weeks and monthsNearly 10,000 children ages 5 to 11 have been hospitalized due to COVID-19.Being vaccinated against COVID-19 helps give children strong protection against serious illness or complications. Although fewer children and teens have had COVID-19 than adults, they can still catch the virus, get sick, and spread it to others. Vaccines can limit how long someone is contagious even if they do get sick. Should I worry about long-term side effects? It is extremely unlikely you will suffer serious side effects that could cause a long-term health problem after getting a COVID-19 vaccine.Long-term side effects following any vaccination are extremely rare. In the past vaccine monitoring has shown that if side effects are going to happen, they tend to happen within six weeks of receiving a vaccine dose.For this reason, the FDA required each of the authorized COVID-19 vaccines to be studied for at least eight weeks after the final dose. Millions of people have received COVID-19 vaccines, and no long-term side effects have been found.The CDC continues to closely monitor COVID-19 vaccines for any safety issues, including problems with manufacturing, a specific lot, or the vaccine itself. If public health experts find any potential safety concerns, FDA and the vaccine manufacturer will work towards a solution. Do vaccines impact fertility? After extensive clinical trials and close examination, doctors have not found any evidence that COVID-19 vaccines cause fertility problems.If you are trying to become pregnant now or want to get pregnant in the future, you may safely receive a COVID-19 vaccine. Could I have an allergic reaction? Severe allergic reactions to vaccines are extremely rare. The FDA says the authorized COVID-19 vaccines appear to be safe for people with common food or environmental allergies.CDC recommends that people get vaccinated even if they have a history of severe allergic reactions not related to vaccines or injectable therapies—such as food, pet, venom, environmental, or latex allergies. People with a history of allergies to oral medications or a family history of severe allergic reactions may also get vaccinated.If you have had an immediate allergic reaction — even if it was not severe — to a vaccine or injectable therapy for another disease, ask your doctor if you should get a COVID-19 vaccine. Your doctor will help you decide if it is safe for you to get vaccinated.All people who get a COVID-19 vaccine should be monitored on site. People who have had any type of severe or immediate allergic reaction in the past should be monitored for at least 30 minutes after getting the vaccine. All other people should be monitored for at least 15 minutes after getting the vaccine. Should I get a vaccine if I have had COVID-19? Yes, health experts recommend getting vaccinated whether or not you have already had COVID-19. Even if you have already recovered from COVID-19, it is possible, but rare, that you could be infected with the virus that causes COVID-19 again. If you’ve had COVID-19 in the past 90 days, talk to your doctor about when you should get vaccinated.While people who’ve already been infected may have some form of natural immunity, studies suggest that immune protection offered by vaccines is more consistent and generates a stronger antibody response. What should I know about vaccines and Guillain-Barré Syndrome? The FDA and CDC are monitoring reports of Guillain-Barré syndrome (GBS) after the Johnson and Johnson vaccine. Such cases have not been reported after the Pfizer or Moderna mRNA vaccines.GBS is a very rare disorder where the body’s immune system damages nerve cells, causing muscle weakness and sometimes paralysis. More than 12 million doses of Johnson and Johnson have been given, with around 100 initial reports of GBS. These cases have largely been reported about 2 weeks after vaccination and mostly in men, many 50 years and older. Public health experts will continue to evaluate reports of GBS after the Johnson and Johnson vaccination.You should seek medical attention right away if you develop any of the following symptoms after getting the Johnson and Johnson vaccine:A weakness or tingling sensation, especially in the legs or arms, that’s worsening and spreading to other parts of the bodyDifficulty walkingDifficulty with facial movements, including speaking, chewing, or swallowingDouble vision or inability to move eyesDifficulty with bladder control or bowel function Will I need a COVID-19 booster shot? Yes, the FDA and CDC recommend all Americans 16 and older get a booster shot at the appropriate time to help protect against highly contagious new variants. If you received the Moderna or Pfizer vaccine, you can get a booster shot if it's at least 6 months after your second dose. If you received the Johnson & Johnson vaccine, you can get a booster shot if it's at least 2 months after your shot.CDC recommendations allow eligible individuals to choose which vaccine they receive as a booster dose. Some people may have a preference for the vaccine type that they originally received, and others may prefer to get a different booster. Consult your doctor or healthcare provider if you’re not sure.A booster shot will help you keep up strong protection against COVID-19, and is especially helpful for people age 65 and older. The recent emergence of the Omicron variant emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19.