How Many People Have Received the Vaccine in the Clinical Trials?
Overall, approximately 39,000 participants aged
6 months and older received at least one dose of Moderna COVID‑19 Vaccine in five clinical trials.
In the largest trial, about 25% of trial participants were 65 years of age and older. About 21% were Hispanic or Latino and 10% were Black.
According to the CDC, as of June 18, 2022, more than 223 million doses of Moderna COVID-19 Vaccine have been administered in the US, and over 77 million people have received the primary series.
What are the Risks of the Vaccine?
There is a remote chance that the vaccine could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to one hour after getting a dose of the vaccine. For this reason, your vaccination provider may ask you to stay at the place where you received your vaccine for monitoring after vaccination. Signs of a severe allergic reaction can include:
- Difficulty breathing
- Swelling of your face and throat
- A fast heartbeat
- A bad rash all over your body
- Dizziness and weakness
Myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) have occurred in some people who have received the vaccine, more commonly in adult males under 40 years of age than among females and older males. In most of these people, symptoms began within a few days following receipt of the second dose of the vaccine. The chance of having this occur is very low. You should seek medical attention right away if you or your child has any of the following symptoms after receiving the vaccine:
- Chest pain
- Shortness of breath
- Feelings of having a fast-beating, fluttering, or pounding heart
- Unusual and persistent irritability
- Unusual and persistent poor feeding
- Unusual and persistent fatigue or lack of energy
- Persistent vomiting
- Persistent pain in the abdomen
- Unusual and persistent cool, pale skin
Side effects that have been reported in clinical trials with the vaccine include:
- Injection site reactions: pain, tenderness and swelling of the lymph nodes in the same arm of the injection or in the groin, swelling (hardness), and redness
- General side effects: fatigue, headache, muscle pain, joint pain, chills, nausea and vomiting, fever, rash, irritability/crying, sleepiness, and loss of appetite
Side effects that have been reported during post‑authorization use of the vaccine include:
- Severe allergic reactions
- Myocarditis (inflammation of the heart muscle)
- Pericarditis (inflammation of the lining outside the heart)
- Fainting in association with injection of the vaccine
These may not be all the possible side effects of the vaccine. Serious and unexpected side effects may occur. The possible side effects of the vaccine are still being studied in clinical trials.Learn about what to expect
What Should I Do About Side Effects?
If you experience a severe allergic reaction, call 9‑1‑1, or go to the nearest hospital.
Call your vaccination provider or your healthcare provider if you have any side effects that bother you or do not go away.
Report vaccine side effects to FDA/CDC Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1‑800‑822‑7967 or report online to https://vaers.hhs.gov/reportevent.html.
Please include either “SPIKEVAX (COVID-19 Vaccine, mRNA)” or “Moderna COVID-19 Vaccine EUA,” as appropriate, in the first line of box #18 of the report form.
You may also be given an option to enroll in v-safe. V-safe is a new voluntary smartphone-based tool that uses text messaging and web surveys to check in with people who have been vaccinated to identify potential side effects after COVID‑19 vaccination. V-safe asks questions that help CDC monitor the safety of COVID‑19 vaccines. V-safe also provides second-dose reminders if needed and live telephone follow-up by CDC if participants report a significant health impact following COVID‑19 vaccination. For more information on how to sign up, visit: https://www.cdc.gov/vsafe.