World Health Organization’s Director-General Dr. Tedros Adhanom Ghebreyesus has warned the global community against an approach suggested by several health authorities to attain “Herd Immunity” through COVID-19 spread rather than vaccination.
The WHO head remarked that very little is known to the global health community about the relatively new novel coronavirus stating “we have some clues, but we don’t have the complete picture” including the level of herd immunity which will be required to tackle the pandemic.
Dr. Ghebreyesus observed the idea of achieving collective immunity as an unrealistic and “unethical” mode of operation. He noted that certain highly infectious diseases like measles require 95 percent of the population to be immunized.
“Herd immunity is achieved by protecting people from a virus, not by exposing them to it,” the WHO Chief commented adding that “Never in the history of public health has herd immunity been used as a strategy for responding to an outbreak.”
He further briefed that his organization has been documenting instances of earlier COVID-19 victims being reinfected with the virus after recovering from the initial infection. Dr. Ghebreyesus shared that while most people appear to develop some kind of immune response it was unclear how long the immunity acquired through infection lasted and how powerful it was to protect against another infection as the immune system works differently on each individual.
Herd immunity (or community immunity) occurs when a high percentage of the population gathers sufficient immunity against disease (through vaccination and/or prior illness), making the spread of this disease from person to person unlikely.
Even individuals not vaccinated (such as newborns and the immunocompromised) are offered some protection because the disease has little opportunity to spread within the community.