Natural Immunity & Reinfection

Should I get vaccinated if I've already had COVID-19? 

Yes. Vaccination after COVID-19 infection has been shown to provide stronger protection than by infection alone [1,2].  Vaccine-based immunity also provides greater protection against variants [3].  Prior infection does provide some short-term immunity, but vaccination will prevent rapid community transmission and get this pandemic under control.

There are other proven treatments available, should I still get the vaccine?  

Yes.  Prevention is always better than treatment. Current treatments for COVID-19 are extremely costly, even with insurance, and can only be administered in hospitals [4].  Vaccines are 100% free.   It is better to choose a preventative option than to roll the dice and possibly go to the hospital, a treatment not working, or wracking up medical debt.  With no approved over-the-counter treatment, vaccines are the cheapest, most accessible technology available.  

Unvaccinated adults:

Unvaccinated adults are 16x more likely to be hospitalized from COVID-19, compared to adults who have completed a primary vaccine series.

High-risk unvaccinated adults:

High-risk unvaccinated adults are 49x more likely to be hospitalized from COVID-19, compared to high-risk adults (65+) who have completed a primary vaccine series and received a booster dose.

-National data provided by Centers for Disease Control and Prevention for December 2021.

Why should I get vaccinated if I can still get infected and transmit COVID-19?   

No vaccine is 100% effective. However, current COVID-19 vaccines have been shown to be extremely successful in preventing infection [5], and more importantly hospitalization and death.  Breakthrough infections are rare, but expected.  Less than 10 in 100,000 vaccinated individuals have been infected with COVID-19 and have died or have been hospitalized [6]. 

Do I even need the vaccine if I have a strong immune system and live a healthy lifestyle?

Yes.  While a balanced diet and healthy lifestyle supports a strong immune system, it does not provide special protection or immunity from infection and transmission of COVID-19 [7].  A healthy person may have a better immune system to fight the virus and stay out of the hospital, but they are still capable of transmitting the virus within the community.  Public health measures play a more important role in infection and transmission, while healthy living provides individual protection from severe illness, hospitalization, and death.

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  1. Cavanaugh AM, et al. Reduced Risk of Reinfection with SARS-CoV-2 After COVID-19 Vaccination — Kentucky, May–June 2021. MMWR Morb Mortal Wkly Rep 2021;70:1081-1083.
  2. Ebinger, J.E., Fert-Bober, J., Printsev, I. et al. Antibody responses to the BNT162b2 mRNA vaccine in individuals previously infected with SARS-CoV-2. Nat Med 27, 981–984 (2021).
  3. Greaney AJ, et al. Antibodies elicited by mRNA-1273 vaccination bind more broadly to the receptor binding domain than do those from SARS-CoV-2 infection. Sci Transl Med. 2021 Jun 30;13(600).
  4. Harvard Health Publishing. Treatments for COVID-19. 2021 Jul 12.
  5. Bernal JL, Andrews N, Gower C, et al. Effectiveness of Covid-19 Vaccines against the B.1.617.2 (Delta) Variant. N Engl J Med. 2021 Jul 21.
  6. Center for Disease Control. COVID-19 Vaccine Breakthrough Case Investigation and Reporting. Updated September 1, 2021. 
  7. 7) Harvard School of Public Health. Nutrition and Immunity. Accessed Aug, 18, 2021.