COVID Infected Patients Show Stronger Immunity to the Delta Variant
Dr. Fabio Pencle, MBA; Dr. Kingsley R. Chin, MBA; Dr. Jason A. Seale, MBA
As new evidence and information are disseminated, the delta variant of COVID-19 continues to create more questions around vaccination. Does everyone need a vaccine? Should countries have vaccine passports?
The recent Israeli study is the largest real-world observational study to date to compare natural versus vaccine-induced immunity to SARS-CoV-2. Results demonstrate that natural immune protection from prior infection was thirteen (13) times more likely to prevent breakthrough infection against the Delta variant compared to people who were vaccinated with BioNTech/Pfizer BNT162b2 mRNA COVID-19 vaccine. [1]
Anonymized Electronic Medical Records (EMRs) were retrieved from the Maccabi Healthcare Services (MHS), Isreal’s second-largest Health Maintenance Organization. The study period of March 1, 2020, to August 14, 2021.
Three groups of patients in the study
1. Double vaccinated
2. Previous COVID-19 infection and unvaccinated
3. Previous COVID-19 infection and single-dose vaccination
The authors concluded “The study demonstrated that natural immunity confers longer-lasting and stronger protection against infection, symptomatic disease and hospitalization caused by the Delta variant of SARS-CoV-2, compared to the BNT162b2 two-dose vaccine-induced immunity. Individuals who were both previously infected with SARS-CoV-2 and given a single dose of the vaccine gained additional protection against the Delta variant.”
This should come as no surprise that natural immunity confers stronger protection. The medical literature documents the different type of immunity: active versus passive. Active immunity is exposure to a disease organism which triggers an immune response to produce antibodies. Exposure to disease from infection results in natural immunity compared to receiving the disease organism through vaccine (vaccine-induced immunity). Passive immunity is when persons are given antibodies to the disease rather than producing. [2]
Patients first have to survive the infectious disease which can lead to organ damage or death to develop natural immunity. This is the rationale for vaccination and why as a form on active immunity it is important to understand. [3-5]
This study overall adds valuable information to the debate. Important takeaway no patients in the study died of COVID-19. The natural immunity group survived prior infection without adverse symptoms. The vaccine is able to prevent serious infection although at a lower rate than natural immunity. In patients who were previously infected and received a single dose, there was a decreased risk of reinfection compared to previously infected only.
The study was conducted in one of the most highly vaccinated countries using a large database that documented several variables, including symptoms and hospitalizations when the Delta Variant predominated in Israel.
Information should be the key driver in making decisions and policies. As the Pandemic continues with Delta Variant only through herd immunity will we be able to move forward? Herd immunity is achieved via a majority of persons contracting the disease which is variable or with the aid of vaccinations.
1. Gazit, S., et al., Comparing SARS-CoV-2 natural immunity to vaccine-induced immunity: reinfections versus breakthrough infections. medRxiv, 2021: p. 2021.08.24.21262415.
2. Immunity Types, in Vaccines. 2021.
3. Price, S., Talk to Patients About: Vaccine Immunity vs. Natural Immunity. Tex Med, 2020. 116(3): p. 47.
4. Kerboua, K.E., The perplexing question of trained immunity vs adaptive memory in COVID-19. J Med Virol, 2020. 92(10): p. 1858-1863.
5. Clem, A.S., Fundamentals of vaccine immunology. J Glob Infect Dis, 2011. 3(1): p. 73-8.
This story first appeared in the August 31st issue of Doctorpreunernews Magazine. Click here to subscribe.
About Authors
Dr. Fabio J. Pencle is a medical doctorpreneur and Associate Professor. He holds a master’s in business administration.
Dr. Kingsley R. Chin is a board-certified Professor of Orthopedic Spine Surgery and honors graduate of Harvard Medical School. See his LinkedIn bio.
Dr. Jason A. Seale is a medical doctorpreneur. He holds a master’s in business administration degree.