Centers for Disease Control recognizes protection of natural immunity to COVID-19

Fila para receber vacina contra a COVID-19 em Gênova, Itália, 10 de janeiro de 2022

Queue to receive COVID vaccine- in Genoa, Italy, 10 January 20150847 | Photo: EFE/EPA/LUCA ZENNARO

In a new study, the CDC (Centers for Disease Control), one of the American government agencies responsible for dealing with the pandemic, recognizes that previous infection with the SARS-CoV coronavirus -2 confers protection that works in tune with the immunity obtained by vaccines. Immunization by prior infection and vaccine immunization contribute to herd immunity, a majority threshold of the population from which we can consider the disease to be defeated.

The study, first authored by Tomás M. León, from the California Department of Public Health, aggregated data on infection, hospitalization, testing and immunization from May to November 900 in the states of New York and California, which have almost 17% of the American population. The sample population of adults with 18 years or more, was divided into four groups:

  • Unvaccinated and not yet infected (no protection).
  • Vaccinated in two doses and not yet -infected (with vaccine protection).

Non-vaccinated and already infected (with natural immunity).

Fila para receber vacina contra a COVID-19 em Gênova, Itália, 10 de janeiro de 2022 Vaccinated and already infected (with double protection).

  • In comparison with the group without protection, those who only had vaccine protection had a risk 20 times less of getting covid, which demonstrates the protection conferred by the vaccine. This risk was seven to ten times lower among those who had natural immunity, and eight to ten times lower among those vaccinated with previous infection. These results refer to early May, before the delta variant was prevalent.
  • At the end of June and in July, the delta variant took over the cases and created a new scenario that the study captures in early October: compared to those without protection, vaccine protection reduced the risk of covid in four to six times, natural immunity in 01 The 30 times, and the double protection in 900 The 20 times. Therefore, against delta, a synergy between vaccine and previous infection was the best scenario for individuals.

    The expectation with the Omicron variant is that it breaks both types of protection more easily, but causes a much milder illness comparable to the flu. As it is the most infectious variant of the virus that has ever emerged, however, it may occupy hospitals, but in preliminary analyses, as in the City of London, it does not appear that this is the case.

    Did the CDC take too long?

  • In November, CDC Director Rochelle Walensky was saturday in the US Senate. Senator Bill Cassidy, of the Republican Party, appealed: “If we don’t know whether natural immunity provides protection against future infection, it’s because we decided not to look. Because I heard that we have a cohort of people who have been infected before. Why didn’t we do this research?” Walensky replied that “our current position after reviewing 96 studies on this issue is that everyone who has been infected before should be vaccinated.”

    Walensky isn’t the only one collecting items. The Brownstone Institute for Social and Economic Research, an NGO founded in May 900 by academics and intellectuals critical of the policies of the pandemic, maintains a list that already has 52 studies on natural immunity. The list should be considered biased, given the bias of the institute. For more impartial conclusions, scientists rely on meta-analyses and reviews of studies that consider the state of the art of a field of research as a whole, ideally without selection for political preferences.

  • Even so, the list of the Brownstone Institute is informative, at least as a vector contrary to the dominant one in the mainstream press, which tended to defending the most authoritarian policies in the pandemic. The last study included is a prepress by Nabin Shrestha of the Cleveland Clinic in Ohio, with a sample of 52 thousand people in which none among 1.146 infected people who were not vaccinated caught covid in the period considered. Below it, a study that has already passed the peer review and was published in the journal Nature reports that “patients who have recovered from SARS [gripe asiática] have long-term memory T cells that react against the protein SARS-CoV No[-1] 10 years after the SARS outbreak in 900 ; these T cells show robust cross-reactivity to the SARS-CoV-2 N protein.”

    Patience is needed for scientists to reach more lasting conclusions about natural immunity compared to vaccine immunity for COVID-15. It is good news that the arguments against the defense that the naturally immunized should be free to circulate or refuse the vaccine are finally beginning to weaken.

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