We have heard a lot about herd immunity in recent days when the British Government and their Prime Minister, Boris Johnson, referred to it as an anti-COVID-19 strategy, the disease caused by the Coronavirus.
In order to contain the spread of the virus, the British Government has proposed not to try to combat the epidemic, but to use the immunity that people will gradually acquire: a strategy based, precisely, on what is known as herd immunity.
Professor Alberto Mantovani, Scientific Director of Humanitas and Professor Emeritus of Humanitas University, spoke about it in an interview with Corriere Della Sera, clarifying not only what is meant by herd immunity but also why this behavior is “irresponsible”.
What is herd immunity?
It is a mechanism that is established within a community so that if the vast majority of individuals are vaccinated, it limits the circulation of an infectious agent. Using this method, it’s possible to protect even those who can not undergo vaccination, perhaps for particular health problems. It is a fundamental mechanism to reduce the circulation and transmission of infectious diseases.
How do you build immunity?
“I don’t like the term herd immunity very much, I prefer to speak of community immunity, where the concept of solidarity is inherent”, explains Professor Mantovani.
“Community immunity is built in two ways: either with a vaccine or spontaneously, as happens for example in the treatment of influenza. At the moment we are not sufficiently prepared for COVID-19, because it is a virus that is practically unknown to us and in general, viruses tend to change with every season. For this reason, it is a practice that is not recommended and it is irresponsible. Immunity will only be achievable with a vaccine”.
Why can’t the English model work without a vaccine?
“You have to think about the price of community immunity obtained not with a vaccine, but by exposing, as has been said, 60% of the British population to the virus. We admit, perhaps optimistically, a mortality rate of 2%. Out of a million people that means 20,000 deaths; out of 10 million people, 200,000 deaths. But let’s count even more dramatically. 10% of the sick need intensive care and assisted respiration. Out of a million people, it will serve 100,000 patients. No healthcare system in the world can cope with such an emergency. There would be too many victims and too many patients would not receive treatment”, continued Professor Mantovani.
According to Professor Mantovani, the restrictive measures taken in Italy are commendable. The Italians who have agreed to live in quarantine through these difficult days are protecting the weakest. The hope is that the rest of Europe will not underestimate this situation and learn the lesson from Lombardy, which boasts one of the most advanced healthcare systems in Europe.