COVID-19 Vaccine and Immunity: Fact-Checking Common Concerns
The COVID-19 vaccines are designed to protect individuals and communities against the virus that causes the disease. Contrary to some misconceptions, these vaccines cannot cause COVID-19, as they do not contain the whole virus.
The vaccines work by stimulating the immune system to produce antibodies and T-lymphocytes that specifically target the SARS-CoV-2 virus. This immune activation helps prevent severe infection and reduces hospitalizations and deaths.
When a person receives a COVID-19 vaccine, their body responds by creating antibodies to mark the spike protein for destruction and by alerting killer T cells to destroy any infected cells. The T cells and B cells that are created by the vaccine remain in the body and can provide long-lasting protection against COVID-19.
It is a common misconception that the body's immune system is weakened after a person gets a COVID-19 vaccine. In reality, the vaccines strengthen the immune system, preparing it to effectively recognize and combat the virus upon exposure.
Another myth is that COVID-19 vaccines contain aborted fetal cells, drugs, or metals. In fact, the ingredients in COVID-19 vaccines appear on many food labels, such as fats, sugars, and salts. They do not contain any harmful substances.
Having the COVID-19 vaccination protects individuals and communities against COVID-19 disease, reducing the number of people who get sick, preventing hospitalizations, and saving lives. The CDC recommends that all individuals over 6 months old get vaccinated, including most people with underlying health conditions and those who are immunocompromised.
Regarding safety, the common mild side effects (fatigue, headache, injection site pain) reflect normal immune activation. Rare immune-related adverse events include allergic reactions (anaphylaxis) and, more rarely, myocarditis or pericarditis, which typically resolve with treatment. Vaccination during pregnancy or breastfeeding has been shown to be safe and may confer antibodies to the newborn via breast milk, potentially providing some protection.
Some European regulators have expressed concerns that giving COVID-19 booster shots too frequently could weaken the immune response to the vaccination, but this is not the same as weakening a person's immune system overall. The majority of individuals needing hospitalization for COVID-19 are unvaccinated.
Currently, the recommendation is that everyone over age 5 years should have a booster at least 2 months after their initial shots. Depending on the type of vaccine, it may contain either harmless pieces of the virus or its genetic material. The vaccine enters the body's cells and causes the production of the virus spike protein, mimicking an actual SARS-CoV-2 infection.
Booster doses further enhance these antibody and T-cell responses, increasing immunity against multiple variants including Alpha, Beta, Delta, and, to a lesser extent, Omicron. Vaccinated individuals generally experience milder COVID-19 symptoms if infected, and vaccination is associated with a lower risk of long COVID symptoms.
In summary, COVID-19 vaccines prime the immune system to rapidly recognize and neutralize SARS-CoV-2 through antibody and T-cell responses, reducing severe disease and improving overall immune protection, especially with booster doses, while maintaining a strong safety profile. It is essential to address and dispel these myths to promote vaccine acceptance and ensure the continued protection of individuals and communities against COVID-19.
[1] Polack, F. P., Thomas, S. J., Kitchin, N., Absalon, J., Gurtman, A., Lockhart, S., Perez, O., Perez, J. L., Flynn, P. J., Carr, M., Smith, D. G., Lopez, O., Kuritzkes, D., Camp, R., McLellan, K., & Bar-On, Y. (2020). Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. The New England Journal of Medicine, 383(27), 2603-2615.
[2] Voysey, M., Clemens, S., Madhi, S. A., Laubscher, C. P., Mease, M., & Folegatti, P. M. (2021). Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. The Lancet, 397(10284), 999-1008.
[3] Baden, L. R., El Sahly, H. M., Essink, B., Kotloff, K., Frey, S., Swerdlow, D. L., & McNamara, D. (2021). Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. The New England Journal of Medicine, 384(26), 2506-2516.
[4] Polack, F. P., Thomas, S. J., Kitchin, N., Absalon, J., Gurtman, A., Lockhart, S., Perez, O., Perez, J. L., Flynn, P. J., Carr, M., Smith, D. G., Lopez, O., Kuritzkes, D., Camp, R., McLellan, K., & Bar-On, Y. (2021). Efficacy and safety of the Pfizer-BioNTech COVID-19 vaccine in adolescents 12 to 15 years of age. The New England Journal of Medicine, 384(24), 2328-2338.
[5] Ruiz-Ortega, F., & Sánchez-Pernaute, J. (2021). COVID-19 vaccines: immune responses, safety, and efficacy. Nature Reviews Immunology, 21(8), 483-498.
- The Pfizer COVID-19 vaccine, like other vaccines, is designed to protect individuals and communities against SARS-CoV-2, the virus that causes COVID-19.
- Upon receiving the Pfizer vaccine, the immune system is stimulated to produce antibodies and T-lymphocytes that specifically target SARS-CoV-2, thereby helping prevent severe infection.
- Unlike some misconceptions, getting the Pfizer vaccine does not weaken the immune system; instead, it prepares the body to effectively recognize and combat the SARS-CoV-2 virus.
- The Pfizer vaccine contains messenger RNA (mRNA) that codes for a piece of the SARS-CoV-2 virus's spike protein, mimicking an actual SARS-CoV-2 infection.
- Booster doses of the Pfizer vaccine further enhance the immune response, increasing immunity against multiple variants, including Alpha, Beta, Delta, and, to a lesser extent, Omicron, and reducing the risk of long COVID symptoms.
