Herd immunity might not work for COVID 19, says a group of scientists
More than two thousand scientists have signed the John Snow Memorandum calling for abandoning the idea of developing herd immunity against COVID-19.
According to the authors, this approach "has no scientific evidence", so its use can be dangerous for the entire population.
High contagiousness, combined with the body's susceptibility to SARS-CoV-2, creates conditions for its rapid spread. The mortality rate from COVID-19 infection is several times higher than from seasonal flu.
Reducing transmission of the virus has been (and continues to be) achieved through physical distancing, the use of face masks, hand and respiratory hygiene.
However, there is a renewed interest in the phenomenon of herd immunity, which involves allowing large, uncontrolled outbreaks of disease in populations with a low risk of severe complications while protecting vulnerable populations.
Proponents of this concept suggest that such outbreaks will lead to the development of post-infectious population immunity in low-risk populations, which will ultimately protect the vulnerable cohort.
However, the authors of the memorandum declared that this is a dangerous delusion, not supported by scientific evidence. Any strategy to deal with a pandemic based on post-infectious immunity against COVID-19 should be considered flawed.
There is no evidence of persistent and active immunity to SARS-CoV-2 after infection. It is unclear how long protective immunity can last, and how likely it is to be re-infected.
In addition, uncontrolled transmission of infection among young and healthy people carries a significant risk of increased morbidity and mortality among the entire population.
This approach can cause labor shortages and the collapse of health systems that are unable to provide emergency and routine care.
Scientists believe that this strategy will not end the COVID-19 pandemic, but will only lead to repeated epidemics, as was the case with numerous infectious diseases in the pre-vaccination era.
Such epidemics would impose an unacceptable burden on the economy and health workers, many of whom have died from COVID-19.
- John Snow Memo: https://www.johnsnowmemo.com/
- Natue: https://www.nature.com/articles/s41586-020-2554-8
#science #covid19 #herdimmunity #coronavirus