COVID-19 (coronavirus disease 2019) is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), discovered in 2019. According to the CDC, as of June 1, 2024, nearly 1.2 million people have died of COVID-19 in the U.S.

According to the CDC, COVID-19 can be very contagious and spread quickly when an infected person breathes out droplets and very small particles that contain the virus. Other people can breathe in these droplets and particles, or these droplets and particles can land on others' eyes, nose, or mouth. In some circumstances, these droplets may contaminate the surfaces they touch. Anyone infected with COVID-19 can spread it, even if they do NOT have symptoms.

People with COVID-19 have a wide range of symptoms ranging from mild symptoms to severe illness. Symptoms may start as mild, and some people will progress to more severe symptoms. Symptoms may change with new virus variants that cause COVID-19 and can vary depending on COVID-19 vaccination status.

Possible symptoms include:

• Congestion or runny nose
• Cough
• Diarrhea
• Fatigue​
• Fever or chills
• Headache
• Muscle or body aches
• Nausea or vomiting
• New loss of taste or smell
• Shortness of breath or difficulty breathing
• Sore throat

This list does not include all possible symptoms. Continue to take CDC-recommended steps even if you do not have symptoms but were exposed to the virus that causes COVID-19.

According to the CDC, staying up to date with COVID-19 vaccines and following preventive measures are especially important if you are older or have one or more health conditions, including those listed below. Also, if you have one or more of the conditions listed, you are more likely to get very sick from COVID-19 and be hospitalized, need intensive care, require a ventilator to breathe, and/or die. The risk of severe illness from COVID-19 increases as the number of risk factors increases. Risk factors include:

Age 50 years or older
Asthma
Cancer
Cerebrovascular disease including stroke
Chronic kidney disease (at any stage)
Chronic liver disease
Chronic lung diseases
Cystic fibrosis
Dementia and other neurological conditions
Diabetes (type 1 or type 2)
Disabilities
Heart conditions including heart failure and possibly high blood pressure
Hemoglobin blood disorders
HIV infection
Immunocompromised condition or weakened immune system
Mental health conditions
Obesity or being overweight
Physical inactivity
Pregnancy or recent pregnancy
Sickle cell disease
Smoking, current or former
Solid organ or blood stem cell transplant
Substance use disorders
Tuberculosis
Use of corticosteroids or other immunosuppressive medications

The list above does not include all possible conditions that put you at higher risk of severe illness from COVID-19. Severe outcomes of COVID-19 are defined as hospitalization, admission to the intensive care unit (ICU), intubation or mechanical ventilation, or death. The conditions on this list are in alphabetical order. They are not in order of risk.

Understanding your increased risk of experiencing severe outcomes of COVID-19 can assist you in making decisions about how to help protect yourself and those you take care of. Take this list with you to review with your doctor at your next appointment. This list should not be used to exclude people with underlying conditions from recommended measures for prevention or treatment of COVID-19. Some people are at increased risk of getting very sick or dying from COVID-19 because of where they live or work, or because they can’t get health care. This includes many people from racial and ethnic minority groups and people with disabilities.

Talk to your healthcare provider, if you have questions about a condition not included on this list or questions on how to manage your condition and help protect yourself against COVID-19 and severe illness.

Visit CDC to learn more. By clicking this link, you will be redirected to a third-party website that is neither owned nor controlled by Pfizer. Pfizer is not responsible for the content or services of this site.

Some people who are immunocompromised are more likely to get very sick with COVID-19. Some examples of immunocompromised conditions include people who have cancer and are on chemotherapy, people who have had a solid organ transplant and are taking medication to keep their transplant and people who use some medicines like corticosteroids for a long time.

Additionally, immune response following COVID-19 vaccination may differ for people who are moderately or severely immunocompromised, hence, specific guidance has been developed. Talk with your healthcare provider.

CDC recommends the 2024-2025 Formula COVID-19 vaccines for people 6 months of age and older.

The virus that causes COVID-19 can change and evolve, and protection from COVID-19 vaccines declines over time. These 2024-2025 formula COVID-19 vaccines are intended to more closely match circulating SARS-CoV-2 strains.

As with other vaccine-preventable diseases, you are best protected from COVID-19 when you stay up-to-date with the recommended vaccinations.

According to the CDC, people who are up to date have lower risk of severe illness, hospitalization and death from COVID-19 than people who are unvaccinated or who have not completed the doses recommended for them by CDC.

Tell your vaccination provider about all of your or your child’s medical conditions, including if you or your child:

• has any allergies
• had a severe allergic reaction after receiving a previous dose of a COVID-19 vaccine
• has had myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the lining outside the heart)
• has a fever​
• has a bleeding disorder or is on a blood thinner​
• is immunocompromised or is on a medicine that affects the immune system
• is pregnant, plans to become pregnant, or is breastfeeding
• has received another COVID‑19 vaccine
• has ever fainted in association with an injection

COVID-19 vaccination side effects can vary from person to person and across age groups. Possible serious side effects may include severe allergic reactions and inflammation of the heart muscle or outer lining of the heart. Common side effects include pain, redness, and swelling in the vaccinated arm. Additionally, some people may experience fever, chills, fatigue (tiredness), headache, muscle aches, and nausea. Contact your healthcare provider if you have a sore arm that worsens in 24 hours, if you experience any concerning side effects, or if your side effects don’t resolve after a few days.

Tell your vaccination provider about all your medical conditions, including if you have any allergies or have had a severe allergic reaction after receiving a previous dose of any COVID-19 vaccine. To learn more, visit the CDC website or call the CDC COVID-19 hotline at 1-800-232-0233. Read more about myocarditis, pericarditis, and severe allergic reactions in the questions below.

According to the CDC, myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) after COVID-19 vaccination are rare. When reported in the US, the cases have especially been among adolescent and young adult males within weeks after receiving the second dose of an mRNA COVID-19 vaccine; however, cases have also been observed in females, in other age groups, and after other doses.

Symptoms of myocarditis and pericarditis include:

• Chest pain
• Shortness of breath
• Feelings of having a fast beating, fluttering, or pounding heart
• Younger children who have myocarditis or pericarditis may have non-specific symptoms such as irritability, vomiting, poor feeding, fast breathing, or fatigue​

Seek medical care if you or your child have any of the specific or general symptoms of myocarditis or pericarditis. Learn more about the risk of myocarditis and pericarditis at CDC.gov.

Severe allergic reactions to vaccines are rare but can happen. Signs of a severe allergic reaction include difficulty breathing or wheezing, a drop in blood pressure, swelling of the tongue or throat, or generalized rash or hives. If you think you might be having a severe allergic reaction after receiving a COVID-19 vaccination, seek immediate medical care by calling 911.

Tell your vaccination provider about all your medical conditions, including if you have any allergies or have had a severe allergic reaction after receiving a previous dose of any COVID-19 vaccine. To learn more, visit the CDC website or call the CDC COVID-19 hotline at 1-800-232-0233.

The CDC recommends COVID-19 vaccination for eligible individuals 6 months of age and older.

The CDC states that the COVID-19 vaccines for children have the same active ingredients as the vaccines given to adults. However, children receive a smaller and more age-appropriate dose that is right for them. COVID-19 vaccine dosage is based on age on the day of vaccination, not on a child’s size or weight. The smaller doses were rigorously tested and found to create the needed immune response for each age group, making it important for your child to get the vaccine made for their age group.​​​

The CDC advises asking your child's healthcare provider for advice about other steps you can take at home to comfort your child after vaccination. It is not recommended to take pain-reliever medicines before vaccination to try to prevent side effects as it is not known how over-the-counter medicines might affect how well the vaccine works.

Here are some common side effects for certain pediatric age ranges:

6 months-3 years:

• Pain in the leg or arm where the shot was given
• Swollen lymph nodes
• Irritability or crying
• Sleepiness
• Loss of appetite

4-17 years:

Side effects are more common after additional doses and can include:

• Pain, swelling, and redness in the arm where the shot was given
• Tiredness
• Headache
• Muscle or joint pain
• Chills
• Swollen lymph nodes

Call a doctor or healthcare provider about a side effect if:

• After leaving a vaccination provider site, if you think your child might be having a severe allergic reaction, seek immediate medical care by calling 911
• Side effects are worrying or do not seem to be going away after a few days

Long COVID is defined as a chronic condition that occurs after SARS-CoV-2 infection and is present for at least 3 months. Long COVID includes a wide range of symptoms or conditions that may improve, worsen, or be ongoing. Long COVID occurs more often in people who had severe COVID-19 illness, but anyone who gets COVID-19 can experience it, including children.

People can be reinfected with SARS-CoV-2 multiple times. Each time a person is infected with SARS-CoV-2, they have a risk of developing Long COVID. Long COVID symptoms and conditions can emerge, persist, resolve, and reemerge over weeks and months. These symptoms and conditions can range from mild to severe, may require comprehensive care, and can even result in a disability.

To learn more visit CDC.gov.

According to the CDC, anyone who had a SARS-CoV-2 infection, the virus that causes COVID-19, can experience Long COVID, including children. While anyone who gets COVID-19 can develop Long COVID, studies have shown that some groups of people are more likely to develop Long COVID than others, including:

• Women
• Hispanic and Latino people
• People who have experienced more severe COVID-19 illness, especially those who were hospitalized or needed intensive care
• People with underlying health conditions and adults who are 65 or older
• People who did not get a COVID-19 vaccine

This is not a comprehensive list. To learn more visit CDC.gov.

People with Long COVID can have a wide variety of symptoms that can range from mild to severe and may be similar to symptoms from other illnesses. Symptoms can last weeks, months, or years after COVID-19 illness and can emerge, persist, resolve, and reemerge over different lengths of time. Long COVID may not affect everyone the same way. Some people can experience health problems from different types and combinations of symptoms that may:

• Be difficult to recognize or diagnose
• Require comprehensive care
• Result in disability

Other commonly reported symptoms (not a comprehensive list):

• General symptoms
  • Tiredness or fatigue that interferes with daily life
  • Symptoms that get worse after physical or mental effort
  • Fever

• Respiratory and heart symptoms
  • Difficulty breathing or shortness of breath
  • Coughing
  • Chest pain
  • Fast-beating or pounding heart (also known as heart palpitations)

• Neurological symptoms
  • Difficulty thinking or concentrating (sometimes referred to as “brain fog”)
  • Headache
  • Sleep problems
  • Dizziness when you stand up (lightheadedness)
  • Pins-and-needles feelings
  • Change in smell or taste
  • Depression or anxiety

• Digestive symptoms
  • Diarrhea
  • Stomach pain
  • Constipation

• Other symptoms
  • Joint or muscle pain
  • Rash
  • Changes in menstrual cycles

Some people with Long COVID have symptoms that are hard to explain or difficult to manage. To learn more, visit CDC.gov.