The approved COVID-19 vaccines have undergone the necessary clinical trials, deeming them safe and effective. And where there is evidence of side effects ranging from mild to severe, the more serious side effects are rare.
All data and statistics are based on publicly available data at the time of publication. Some information may be out of date. Visit our coronavirus hub for the most recent information on the COVID-19 pandemic.
The above information comes from the
- mRNA vaccines
- vector vaccines
- protein subunit vaccines
However, in the United States, protein subunit vaccines are not in common use compared with other types.
This article explores how the vaccine works, the different types, and the benefits and risks of each.
Some people may experience mild side effects that can last for a few days. However, very few individuals may experience severe side effects, such as anaphylaxis, and require immediate medical attention. If these serious side effects occur, a person should dial 911 or consult an emergency department.
Anaphylaxis is a severe allergic reaction that can be life threatening. The symptoms develop suddenly and include:
- swelling of the face or mouth
- fast, shallow breathing
- a fast heart rate
- clammy skin
- anxiety or confusion
- blue or white lips
- fainting or loss of consciousness
If someone has these symptoms:
- Check whether they are carrying an epinephrine pen. If they are, follow the instructions on the side of the pen to use it.
- Dial 911 or the number of the nearest emergency department.
- Lay the person down from a standing position. If they have vomited, turn them onto their side.
- Stay with them until the emergency services arrive.
Some people may need more than one epinephrine injection. If the symptoms do not improve in 5–15 minutes, or they come back, use a second pen if the person has one.
The COVID-19 vaccine conditions a person’s immune system to respond to SARS-CoV-2, the virus that causes the disease, without causing an infection. Since 2020, laboratories worldwide have developed different vaccines that serve the same purpose.
When SARS-CoV-2 passes from one person to another, it causes an infection that attacks the body. The immune system uses white blood cells to defend the immune system. Of the overall white blood cells in the body, lymphocytes make up
- Macrophage: Fight the infection by removing germs and cells that are no longer functional. They leave behind parts of the germs, known as antigens. The body identifies these as dangerous and stimulates “attacking” antibodies.
- B lymphocytes: These produce antibodies, follow the macrophages, and attack part of the virus that remains.
- T lymphocytes: This type of defensive white blood cell attacks healthy body cells that carry infections.
After a viral infection, some lymphocytes that have attacked the virus remain in the body, ready to respond if the infection returns.
The T lymphocytes recognize the virus act quickly if the body encounters the same virus. The B lymphocytes recall how to fight it and produce antibodies to attack the virus.
It takes a few weeks after vaccination for the body to produce these T lymphocytes and B lymphocytes.
COVID-19 is still a relatively young virus, and the development of vaccines was a rapid process. However, coronaviruses are not new.
Despite their fast production, the approved vaccines for COVID-19 have undergone the necessary clinical trials. Additionally, there have been tens of thousands of participants in each of these trials.
As of March 30, 2022, over 217 million people in the U.S. have received both vaccine doses. Additionally, over 97 million individuals have had a booster dose of the vaccine.
However, the vaccine can
The following manufacturers have produced vaccines that currently have approval in the U.S.:
- Johnson and Johnson
Pfizer-BioNTech has manufactured a messenger RNA, or mRNA, vaccine. The vaccine works by using a piece of mRNA to instruct cells in the body on how to
The Pfizer vaccine is safe for people aged
However, the Pfizer vaccine can cause complications for certain people. Individuals should not have the vaccine if they are allergic to any of its ingredients. If there is an allergic reaction after the first dose, they should not have a second dose of the mRNA vaccine.
As with the Pfizer vaccine, the Moderna vaccine can pose a risk for people who are allergic to the ingredients. If a person has an allergic reaction from the first mRNA dose, they should not have a second dose of Moderna.
In rare situations, young people have experienced myocarditis or pericarditis after having the Moderna mRNA vaccine.
Johnson and Johnson’s Janssen vaccine is a viral vector vaccine. These types of vaccines work by
The Johnson and Johnson vaccine is appropriate for individuals who are
It has higher safety risks than the other two types, as there may be a link between the Johnson and Johnson vaccine and blood clots. However, the likelihood is extremely low, affecting a rate of 3.83 people in every million. In some cases, it has been fatal.
Additionally, individuals should avoid the vaccine if they are allergic to any of its ingredients. They should also not have a second dose of the same vaccine if they have an allergic reaction to the first.
Despite some health implications, the Johnson and Johnson viral vector vaccine is generally safer than not having a vaccine, and it is the best option for people at risk from mRNA vaccines.
- Guillain-Barré Syndrome
- thrombosis with thrombocytopenia syndrome (TTS)
As of May 5, 2022, the FDA
If a person experiences a rare side effect from the vaccine, they should seek medical assistance immediately or dial 911.
Additionally, they can report the incident to the Vaccine Adverse Event Reporting System after recovery.
Overall, the benefits of any COVID-19 vaccine are
Note that the risk of death or hospitalization from COVID-19 is considerably
COVID-19 vaccines effectively enable the body to build up immunity to the virus without having an infection.
Though researchers developed these vaccines rapidly, those vaccines that currently have approval in the U.S. have undergone all the necessary clinical trials. Scientists developed these vaccine production techniques before the discovery of COVID-19, using the principles from managing other coronaviruses, such as SARS and MERS.
Overall, the advantages of the Pfizer and Moderna mRNA vaccines and the Johnson and Johnson viral vector vaccine outweigh the risks.