By Daniel Levi
In recent days, the FDA approval of Pfizer vaccines and vaccine mandates by employers and other organizations have managed to suck the oxygen out of the 24-hour news cycle. However, while vaccines and therapeutics play major roles in combating the deadly covid-19, what’s less talked about is the role of natural immunity in protecting people against the SARSCoV2 virus.
With the report of waning vaccine-induced immunity against COVID-19 beginning to surface, a new study was conducted in Israel to compare different immunities.
“The short-term effectiveness of a two-dose regimen of the BioNTech/Pfizer BNT162b2 mRNA COVID-19 vaccine was demonstrated in clinical trials and in observational settings3,4. However, long-term effectiveness across different variants is still unknown, though reports of waning immunity are beginning to surface, not merely in terms of antibody dynamics over time5–7, but in real-world settings as well. Alongside the question of long-term protection provided by the vaccine, the degree, and duration to which the previous infection with SARS-CoV-2 affords protection against repeated infection also remains unclear.”
According to two new studies from the UK and Israel, researchers found that natural immunity is far superior and much better than artificial immunity derived from vaccines as part of the largest real-world observational study.
“This is the largest real-world observational study comparing natural immunity, gained through previous SARS-CoV-2 infection, to vaccine-induced immunity, afforded by the BNT162b2 mRNA vaccine. Our large cohort, enabled by Israel’s rapid rollout of the mass-vaccination campaign, allowed us to investigate the risk for additional infection – either a breakthrough infection in vaccinated individuals or reinfection in previously infected ones – over a longer period than thus far described.”
As part of the study, which is now published on the medRxiv preprint server, researchers compared three cohort groups: Group 1 consists of SARS-CoV-2-naïve individuals who received a two-dose regimen of the BioNTech/Pfizer mRNA BNT162b2 vaccine. The second group consists of previously infected individuals who have not been vaccinated, and the third group consists of previously infected and single-dose vaccinated individuals.
According to the published paper, “The study population included MHS members aged 16 or older who were vaccinated prior to February 28, 2021, who had a documented SARSCoV-2 infection by February 28, 2021, or who had both a documented SARS-CoV-2 infection by February 28, 2021, and received one dose of the vaccine by May 25, 2021, at least 7 days before the study period. On March 2, 2021, The Israeli Ministry of Health revised its guidelines and allowed previously SARS-CoV-2 infected individuals to receive one dose of the vaccine, after a minimum 3-month-interval from the date of infection.”
After the grouping, the results show that “a total of 673,676 MHS members 16 years and older were eligible for the study group of fully vaccinated SARS-CoV-2-naïve individuals; and 62,883 were eligible for the study group of unvaccinated previously infected individuals and 42,099 individuals were eligible for the study group of previously infected and single-dose vaccinees.”
At the end of the study, researchers found that vaccinated people were 13 times as likely to be infected and 27 times to have symptomatic infections as a matched cohort that was previously infected with the Delta variant. The paper also shows that offering previously infected people one dose slightly reduced their infection risk (probably not enough to outweigh side effects).
“Our analysis demonstrates that SARS-CoV-2-naïve vaccinees had a 13.06-fold increased risk for breakthrough infection with the Delta variant compared to those previously infected, when the first event (infection or vaccination) occurred during January and February of 2021. The increased risk was significant for a symptomatic disease as well.”
Now, here is the second section of the result that should put an end to the debate over vaccines versus natural immunity.
“Although the results could suggest waning natural immunity against the Delta variant, those vaccinated are still at a 5.96-fold increased risk for breakthrough infection and at a 7.13-fold increased risk for symptomatic disease compared to those previously infected. SARS-CoV-2-naïve vaccinees were also at a greater risk for COVID-19-related-hospitalization compared to those who were previously infected. Individuals who were previously infected with SARS-CoV-2 seem to gain additional protection from a subsequent single-dose vaccine regimen.”
Hats off to the former New York Times reporter Alex Berenson who first spotted the Israeli study. In a tweet this evening.
Here is another Israeli study with similar results.
Ran Israeli on Twitter: “According to the recent Israeli data – A few months after receiving the 2nd shot – there is NO DIFFERENCE between vaxxed/unvaxxed in terms of cases&viral transmission.However, previously infected people are way more protected than fully vaccinated peoplehttps://t.co/MGyvxlMnkk / Twitter”
According to the recent Israeli data – A few months after receiving the 2nd shot – there is NO DIFFERENCE between vaxxed/unvaxxed in terms of cases&viral transmission.However, previously infected people are way more protected than fully vaccinated peoplehttps://t.co/MGyvxlMnkk
That’s not all. Another study conducted in the UK shows that natural immunity offers much better protection. In the tweet below, a Twitter user by the name of Corona Reduit shared some of the findings from the UK study.
In response to Berenson’s post, Reduit tweeted:
“Natural immunity protects MUCH BETTER than vaccination in UK Reinfections with #delta = 0.7% of cases Vaccine breakthroughs with #delta = 15% of cases, soon more Vaccination only started 6 months ago, disadvantages will grow Regional distribution shows reinfection protection.”
Corona Reduit on Twitter: “this was apparent from UK reinfection data as wellhttps://t.co/E4Hs98U1xN / Twitter”
this was apparent from UK reinfection data as wellhttps://t.co/E4Hs98U1xN
Below is the summary of the Israeli study.
Reports of waning vaccine-induced immunity against COVID-19 have begun to surface. With that, the comparable long-term protection conferred by previous infection with SARS-CoV-2 remains unclear.
We conducted a retrospective observational study comparing three groups: (1)SARSCoV-2-naïve individuals who received a two-dose regimen of the BioNTech/Pfizer mRNA BNT162b2 vaccine, (2)previously infected individuals who have not been vaccinated, and (3)previously infected and single dose vaccinated individuals. Three multivariate logistic regression models were applied. In all models we evaluated four outcomes: SARS-CoV-2 infection, symptomatic disease, COVID-19-related hospitalization and death. The follow-up period of June 1 to August 14, 2021, when the Delta variant was dominant in Israel.
SARS-CoV-2-naïve vaccinees had a 13.06-fold (95% CI, 8.08 to 21.11) increased risk for breakthrough infection with the Delta variant compared to those previously infected, when the first event (infection or vaccination) occurred during January and February of 2021. The increased risk was significant (P<0.001) for symptomatic disease as well. When allowing the infection to occur at any time before vaccination (from March 2020 to February 2021), evidence of waning natural immunity was demonstrated, though SARS-CoV-2 naïve vaccinees had a 5.96-fold (95% CI, 4.85 to 7.33) increased risk for breakthrough infection and a 7.13-fold (95% CI, 5.51 to 9.21) increased risk for symptomatic disease. SARS-CoV-2-naïve vaccinees were also at a greater risk for COVID-19-related-hospitalizations compared to those that were previously infected.
This 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.
You can read the full study on the medRxiv preprint server.