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 COVID-19 virus to others and 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.
Furthermore, it prevents the COVID-19 virus from spreading and replicating, which allows it to mutate and possibly become more resistant to vaccines.
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 male adolescents and young adults age 16 and older. Myocarditis is the inflammation of the heart muscle, while pericarditis is the inflammation of the lining outside the heart. These reports are rare. The CDC is investigating to see if there is any relationship to COVID-19 vaccination.
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.
Do the COVID-19 vaccines protect against the COVID-19 variants?
The COVID-19 vaccines were developed based on the S protein before it contained the mutations identified in the variants. While research suggests that COVID-19 vaccines have lower efficacy against the variants, the vaccines still appear to provide protection against severe COVID-19. Further research is needed.
In addition, vaccine manufacturers are also creating booster shots to improve protection against variants.
What are the possible 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 likely be monitored for 15 minutes after getting a COVID-19 vaccine to see if you have an immediate reaction. Most side effects happen within the first three days after vaccination and typically last only one to two days.
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
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 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 your first vaccine dose:
- Continuous shortness of breath or wheezing
- Swelling of the lips, eyes or tongue
- Redness, swelling or itchiness in areas of the body other than the limb in which the vaccine was given
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.
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.
Can pregnant or breastfeeding women get the COVID-19 vaccine?
If you are pregnant or breastfeeding, you may choose to get a COVID-19 vaccine. While further research is needed, early findings suggests that getting an mRNA COVID-19 vaccine during pregnancy poses no serious risks. The findings are based on data from the CDC’s coronavirus vaccine safety monitoring system.
If you have concerns, talk to your health care provider about the risks and benefits.
Keep in mind that the mRNA COVID-19 vaccines don’t alter your DNA or cause genetic changes.
Can I still get COVID-19 after I’m vaccinated?
COVID-19 vaccination will protect most people from getting sick with COVID-19.
A very small percentage of fully vaccinated people will still get COVID-19 if they are exposed to the COVID-19 virus. These are called vaccine breakthrough cases. Some people might not experience any symptoms and some people could become sick due to COVID-19.
However, vaccination 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.