A group of 80 researchers warned this Wednesday, 14, in a letter to the journal The Lancet, which approaches on herd immunity for managing covid-19 it is a “dangerous fallacy” in allowing immunity to develop in low-risk populations while protecting the most vulnerable. According to them, this strategy “is not supported by scientific evidence”. The warning was given before the second wave of new coronavirus that affects Europe, with more than one million deaths worldwide due to the disease.
In the document, scientists from universities in different countries, such as United Kingdom, United States, Germany e Italy, and from different health fields, presented observations of the scientific consensus on understanding covid-19, in addition to the strategies that need to be implemented to protect societies and economies. They say that in the early stages of the pandemic, many countries lockdown to reduce the spread of the virus, which “was essential in decreasing mortality, protecting health services from being overwhelmed and gaining time to articulate response systems to suppress transmission”.
However, the researchers acknowledge that the measure had impacts on people’s physical and mental health, as well as threatening the economy of nations, being worse in those that failed to establish an effective control system. “This, understandably, has led to widespread demoralization and decreased confidence. The arrival of a second wave and an understanding of the challenges ahead has led to renewed interest in so-called herd immunity, which suggests allowing a large uncontrolled outbreak in the population of low risk while protecting the vulnerable “, they claim, and then say that” this is a dangerous fallacy not supported by scientific evidence “.
Scientists justify that any pandemic based on covid-19’s natural infection immunity is flawed and that uncontrolled transmission in younger people would pose a significant risk of mortality across the population. They also point out that there is no evidence of lasting immunity to Sars-CoV-2 after infection and endemic transmission, the result of decreasing immunity, “would pose a risk to vulnerable populations for an indefinite future.” Rather than ending the pandemic, the move would result in repeated waves of transmission for many years.
Also on Wednesday, 15 public health organizations in the United States spoke out against the strategy of using herd immunity to control the spread of the new coronavirus. The statement was a response to a manifesto allegedly written by scientists and non-scientists called Great Barrington. The institutions claim that the propositions are not based on science, ignore sound knowledge of public health and “would randomly and unnecessarily sacrifice lives”. Furthermore, they consider the manifesto to be political, not strategic.
“Fighting the pandemic with blockades or full reopening is not a binary choice, we need to adopt common sense public health practices that allow a safe reopening of the economy and a return to work and face-to-face learning, while using proven strategies to reduce the spread of the virus “, they defend. In August, the director of the emergency program at World Health Organization stated that the herd immunity is not the “salvation” of the pandemic and that one could not live in the hope of that.
For the scientists who wrote the letter to The Lancet, it is essential to act decisively and urgently. “Effective measures to suppress and control transmission need to be widely implemented and supported by financial and social programs that encourage community responses and address the inequalities that have been magnified by the pandemic,” they say. For them, continuous restrictions are likely to be needed in the short term to avoid future lockdowns. “The protection of our economies is closely linked to the control of covid-19. We must protect our workforce and avoid long-term uncertainty.”
The authors conclude that the evidence is clear: “Controlling the community spread of covid-19 is the best way to protect our societies and economies until safe and effective vaccines and therapies arrive in the coming months. We cannot allow distractions to undermine an effective response. “.