London: The so-called herd immunity approach to manage coronavirus pandemic by “allowing immunity to develop in low-risk populations while protecting the most vulnerable is a dangerous fallacy unsupported by the scientific evidence,” warned an international group of 80 researchers.
The open letter, referred to by its authors as the John Snow Memorandum, is published by The Lancet. It is signed by 80 international researchers (as of publication) with expertise spanning public health, epidemiology, medicine, paediatrics, sociology, virology, infectious disease, health systems, psychology, psychiatry, health policy, and mathematical modelling.
“It is critical to act decisively and urgently. Effective measures that suppress and control transmission need to be implemented widely, and they must be supported by financial and social programmes that encourage community responses and address the inequities that have been amplified by the pandemic,” the letter mentioned.
The authors explained that there is no evidence for lasting protective immunity to SARS-CoV-2 after natural infection, and warn that this waning immunity as a result of natural infection would not end the COVID–19 pandemic.
The herd immunity approach could place vulnerable populations at risk for the indefinite future, as natural infection-based herd immunity strategies would result in recurrent epidemics, as seen with many infectious diseases before mass vaccination, the scientists said.
While special efforts to protect the most vulnerable are essential, they said these must go hand-in-hand with multi-pronged population-level strategies.
“Effective measures that suppress and control transmission need to be implemented widely, and they must be supported by financial and social programmes that encourage community responses and address the inequities that have been amplified by the pandemic,” they wrote in the letter.
According to the scientists, the restrictions can effectively suppress the number if infections to low levels that allow rapid detection of localised outbreaks.
“Continuing restrictions will probably be required in the short term, to reduce transmission and fix ineffective pandemic response systems, in order to prevent future lockdowns. The purpose of these restrictions is to effectively suppress SARS-CoV-2 infections to low levels that allow rapid detection of localised outbreaks and rapid response through efficient and comprehensive find, test, trace, isolate, and support systems so life can return to near-normal without the need for generalised restrictions,” the letter read.
“Protecting our economies is inextricably tied to controlling COVID-19. We must protect our workforce and avoid long-term uncertainty,” they said.
According to the scientists, vulnerable populations are at risk for the indefinite future, as natural infection-based herd immunity strategies would result in recurrent epidemics, as seen with many infectious diseases before mass vaccination. So they called for controlling the spread of the virus until the population can be vaccinated.
Natural infection-based herd immunity approaches risk impacting the workforce as a whole and overwhelming the ability of healthcare systems to provide acute and routine care, the researchers warned.
Source: Live Mint