COVID-19

While most people with COVID-19 get better within weeks of being sick, some people experience post-COVID conditions (PCC) known as “Long COVID,” “Long Haul COVID,” or “Chronic COVID.”

PCCs are a wide range of new, returning, or ongoing health problems people may experience at four or more weeks after being infected with the virus that causes COVID-19. Even people who did not have COVID-19 symptoms in the days or weeks after they were infected with the virus can have PCCs and/or combinations of health problems for different lengths of time.

Medical and public health experts are also looking into a rare, but serious medical condition associated with COVID-19 called Multisystem Inflammatory Syndrome (MIS) that can occur in both children (MIS-C) and adults (MIS-A). MIS is a health condition where different body parts can become inflamed, including the heart, lungs, kidneys, brain, skin, eyes, or gastrointestinal organs. Experts do not yet know what causes MIS. However, they do know that people with MIS had the virus that causes COVID-19 or had been around someone with COVID-19. MIS can be serious, even deadly. There have been very few cases of MIS-C reported in the U.S. Learn more about MIS-C and its symptoms.

The virus that causes COVID-19 can change over time. Most of the time this does not change the virus’ properties, but sometimes changes can affect how easily the virus spreads, how infectious it is, how it reacts to a vaccine or medication, and the severity of disease it can cause.

There are multiple variants of this virus that circulate around the world all the time. Some of these variant viruses—like the Omicron variants—spread more easily and quickly than others, and some cause more serious illness.

The best way to protect yourself and your loved ones against virus variants is to get vaccinated with the seasonal updated COVID-19 vaccine every year.

COVID-19 vaccines provide vaccinated people with protection against serious illness, hospitalization, and death due to COVID-19.

COVID-19 vaccines, like all vaccines, are not 100% effective at preventing disease. It is possible to sill contract COVID-19 once you are vaccinated, known as a “breakthrough infection.”

Additionally, people who are moderately or severely immunocompromised due to illness or treatments may not be as protected by the vaccines as those with stronger immune systems and may need additional doses of a COVID-19 vaccine.

However, fully vaccinated people with a vaccine breakthrough infection ARE LESS LIKELY to develop serious illness than those who are unvaccinated and get COVID-19. Even when vaccinated people develop symptoms, they tend to be less severe symptoms than in unvaccinated people. This means they are much less likely to be hospitalized or die than people who are not vaccinated.

Unprecedented times called for a quick turnaround of safe and effective COVID-19 vaccines. While steps to develop the vaccines were streamlined or overlapped, none of them were skipped. Vaccine safety was—and continues to be—a top priority in all phases of vaccine development (clinical trials), authorization/approval, and post-authorization/post-approval monitoring.

Learn more about the development process of COVID-19 vaccines here.

Receiving a COVID-19 vaccine during pregnancy is safe. There have been numerous steps taken to ensure that COVID-19 vaccines will not cause harm to you or your baby. Learn more from CDC here and from the American College of Obstetricians and Gynecologists (ACOG) here.

Extensive evidence from large cohort studies of tens of thousands of pregnant women show that COVID-19 vaccines do not increase the risk of pregnancy complications or other adverse outcomes, and leading medical authorities recommend COVID-19 vaccination during pregnancy.

Additionally, large studies tracking birth outcomes have demonstrated that COVID-19 vaccines administered during pregnancy do not increase the likelihood of congenital anomalies or birth defects in newborns.

Data show that COVID-19 vaccination during pregnancy protects both mother and baby from severe COVID-19, as pregnancy increases risk for severe illness and complications from infection, and antibodies from vaccination can provide newborns with some level of temporary immunity. Vaccination during pregnancy has also been show to decrease the risk of stillbirth.

Messenger RNA (mRNA) is a molecule that is found in all of our cells and each mRNA carries the instructions for making specific proteins. When a protein needs to be made, the mRNA moves from the nucleus of the cell into the cellular fluid. The fluid contains organelles called ribosomes that then read the mRNA code and create the protein.

The mRNA in the vaccine also codes for a protein. It codes for a spike protein that’s on the outside of the coronavirus. The mRNA in the vaccine enters the fluid of the cell to work with the ribosomes and make the coronavirus spike protein. The vaccine mRNA cannot cross into the nucleus of the cell and therefore cannot get near your DNA to alter it or cause mutations of any kind.

Once the protein is made, your immune system will recognize that this protein is different from the other proteins in the body and will respond by attacking it and eventually forming antibodies to it. Just as it would if you were infected with the coronavirus naturally.

The mRNA quickly degrades inside your body and doesn’t stick around. You don’t need to be worried about any extra mRNA floating around in your cells.

There’s no infectious agent in mRNA COVID-19 vaccines. So, there’s no way you’re going to get sick with COVID-19 from an mRNA vaccine.

No, it is not possible for mRNA vaccines to enter, alter, or disrupt our DNA.
There are three reasons why it is impossible for mRNA to change your DNA.

1. Within the cell is a compartment known as the nucleus where all of your DNA is stored. DNA serves as the genetic code for our bodies. Surrounding the nucleus is a barrier known as the “nuclear membrane.” mRNA lives in the cytoplasm of our cells, outside of the nucleus, and makes proteins for our bodies. To enter through this barrier of the nuclear membrane, mRNA would need a signal molecule that allows for entry. mRNA does not have one, therefore, it cannot possibly travel into the nucleus.
2. Even if the mRNA were able to enter the nucleus AND transform into DNA, it has to be integrated into the DNA to make any change. For this to happen the vaccine would also need to contain a protein known as “integrase.” The vaccine does not contain this protein.
3. It is very difficult for RNA to become DNA, and the vaccine does not provide the proteins needed to make such a change. Therefore, mRNA from the vaccine will not become DNA.

So, for these three reasons it is not possible for mRNA within a COVID-19 vaccine to affect DNA.

The Vaccine Adverse Event Reporting System (VAERS) is a key tool for vaccine safety. The system is in place to serve as an early warning system. Anyone can report health events through VAERS after vaccination, but these reports are not verified and do not prove a vaccine caused the event.

Public health agencies like the CDC and FDA monitor VAERS and investigate reports, including deaths, to understand if there is a causal link.

Despite some false claims from critics, VAERS monitoring is robust and taken very seriously. Healthcare providers and vaccine manufacturers are legally required to report certain events after vaccination.

The self-reporting in VAERS is just a starting point—once a report is filed and classified as serious, medical experts examine details such as medical records, death certificates, and autopsy findings to determine whether there is any evidence the vaccine played a role. Most of the time, investigation determines that reports of adverse events are unrelated or coincidental, but in some cases VAERS has helped identify real vaccine risks.

In the late 1990s, VAERS reports identified an increased risk of intussusception (a type of bowel obstruction) after the original rotavirus vaccine was introduced. This early warning led to the vaccine being withdrawn, preventing further harm, demonstrating the important role VAERS plays in identifying rare but serious vaccine-related risks.

Large-scale safety monitoring in millions of children shows that serious side effects from COVID-19 vaccines, like myocarditis, are very rare, and when it does occur cases are typically mild and resolve on their own.

It’s important to note that COVID-19 infection is far more dangerous for children than vaccination. For example, the risk of myocarditis in boys age 5-11 is more than five times higher among those infected with COVID-19 compared to the risk related to vaccination COVID-19 was per a 2021 CDC study.

Notably, vaccine safety monitoring has shown no association between COVID-19 vaccination and myocarditis over the last three years, including the 2022-2023 and 2023-2024 vaccines and the 2024-25 vaccine to date.

According to CDC data, COVID-19 was the 12^th leading cause of death in children and teens in the U.S. 2023.

No confirmed pediatric deaths have been causally linked to COVID-19 vaccines and misleading claims about pediatric deaths rely on misrepresentation of reports in the Vaccine Adverse Event Reporting System (VAERS).

The VAERS platform is a self-reporting system where anyone can submit a report, even if the events reported are not actually causally related to a vaccine. Reports are not verified and cannot provide causation, which means citing raw VAERS reports as evidence of harm can be misleading and misrepresent risks of vaccines.

Every serious adverse event or death reported to VAERS is reviewed by public health experts at CDC and FDA, and if concerns are identified, further investigation and follow-up are conducted to determine whether the vaccine played a role.