A team of researchers from Maccabi Healthcare Services in Tel Aviv, Israel, presented a preprint – which has not yet been peer-reviewed – demonstrating that patients who had been infected with COVID had stronger protection against reinfection with the delta strain than people who had been vaccinated.
Unfortunately, some interpreted this to indicate that acquiring COVID is a better option than vaccination.
To begin, the hypothesis that a COVID infection results in more durable protection than vaccination is not implausible. Our immune system is exposed to several viral proteins during infection, but the most commonly used COVID vaccines introduce a single antigen: the spike protein. As a result, the immune response is more targeted but also more constrained than it is following infection.
Although individuals who have had COVID can catch infection again, naturally acquired immunity continues to evolve over time, and antibodies are detectable for a longer period of time than initially assumed. Immunity following both severe and mild infection appears to protect against both symptomatic and asymptomatic reinfection, according to new findings.
Apart from the risk of taking conclusions from data that has not yet been examined by other scientists, it is equally critical to place the data in the proper perspective. Although the study emphasizes the importance of naturally acquired immunity, it does not take into account the risks associated with gaining natural immunity through infection. It also has no effect on vaccine-induced immunity.
In reality, the study does not even examine the benefit of vaccination because unvaccinated patients with no prior infection were not included for comparison. The low risk of COVID-related hospitalizations among vaccinated participants (eight out of 16,000) is likely to be significantly lower than among non-vaccinated patients without prior infection, however, this group was excluded from the analysis.
One prevalent reason for not being vaccinated is the mistaken belief that waiting for natural immunity through illness rather than vaccination is a possibility. However, infection-acquired immunity may come at a high price.
Aside from the obvious risks of severe illness or death, several recent studies show that most other healthy people who have recovered from COVID have a significantly increased risk of long-term serious health problems such as myocarditis (inflammation of the heart muscle), blood clots, and stroke when compared to vaccinated people. Furthermore, the most stringent safety monitoring in US history has demonstrated that COVID vaccinations are both effective and safe.
With infections on the rise worldwide and deaths caused by the delta variant, waiting for infection – and risking long-term health problems, severe sickness, and death – to develop immunity to the same infection is as pointless as it is deadly.
The Israeli preprint, on the other hand, sheds light on our growing understanding of the powerful immunity created by receiving the vaccination after having COVID — a phenomenon known as hybrid immunity. Several studies suggest a significant increase in both antibody and T-cell responses to vaccination in patients who have previously been infected with COVID.
According to a recent Centers for Disease Control and Prevention report, those who recovered from COVID and were later vaccinated had half the chance of reinfection as unvaccinated people who had previously had COVID. Even if you have previously had COVID, it is still recommended to obtain the vaccine.
The potent immune booster that results from the combination of natural immunity plus a single subsequent vaccine injection raises the question of whether one dosage is sufficient for persons who have had COVID. Several studies have found that immune responses to a single dose of either the Pfizer or AstraZeneca vaccines outperform those to two doses in people who have never been infected.
As a result, several nations, including France, Italy, and Germany, now suggest a single treatment for patients who have previously been infected with COVID. In addition, illness without immunisation is recognized as immunity under current Israeli green pass regulations.
Although directing boosters to persons who have not been infected may make better use of limited vaccination supplies, personalized schedules and exemptions from vaccination mandates may be logistically challenging in the midst of a pandemic. Antibody screening prior to vaccine is time-consuming and costly, and it creates practical difficulties in determining who has or has not previously had COVID. These exemptions may slow rather than speed up vaccine deployment.
As enormous research efforts bring knowledge regarding human immunological responses to COVID infection and immunizations on a daily basis, we must critically examine the data and all of the facts that surround it. We are still a long way from ending the pandemic, and the risk of infection are undeniable. Our top priority should be to limit the spread of disease and get vaccines to people who are still unvaccinated and in desperate need of them. It makes little sense to forgo vaccination by waiting for infection and hoping for natural immunity.
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