Herd Immunity is not Guaranteed with 70% of Population Vaccinated

MEDICAL experts in public health and immunologists from the Barcelona Institute of Global Health (ISGlobal) consider that “it is not clear” the percentage of the vaccinated population necessary to achieve group immunity and they do not consider it “safe” to reach 70 per cent of the vaccinated population.

As reported by Andalucia Informacion, in a report signed by the Public Health doctor of the Hospital Clínic, Clara Marín; the ISGlobal analysis coordinator, Oriana Ramírez; the immunologists Carlota Dobaño, Gemma Moncunill and Adelaida Sarukhan, and the head of the ISGlobal Health Systems research group, Jeffrey V. Lazarus, warn that “there is no magic percentage of immunisation that provides herd immunity against a pathogen.”

“It is not even certain that this goal is possible, the claim that we will achieve herd immunity in 100 days is based more on logistics than epidemiology,” they say, although they acknowledge that, if there are no delays in the arrival of vaccines committed, there will be enough doses to meet the government’s objectives of having 70 per cent of the population vaccinated in August or September.

The fact that there are asymptomatic infections among the population, that the virus itself is mutating and that there are more contagious variants has led some epidemiologists to raise the necessary number of immunisation to 85 per cent of the vaccinated population or with antibodies for having passed the disease. But, in addition, they add that there is another key factor, which is whether immunisation is distributed equally. “If there is 90 per cent vaccination coverage in one geographical area and 60 per cent in another, for example, the general percentage of vaccination will not reflect reality,” warn the experts, who also address the fact that the child population will not yet be vaccinated.