One of the theories put forward by scientists to explain why some people have managed to dodge the infection has to do with the innate immunity: the first barrier that our body forges to deal with external ‘threats’. “There are people who have this first barrier of much more resistant ‘immunological machinery’ than the rest. Thus, in case of coming into contact with the coronavirus, they get control the virus much more effectively and prevent the infection from spreading to other organs”, explains the immunologist Julià Blanco, from IrsiCaixa.
The strength of innate immunity, explains Blanco, depends on a wide range of genetic and biological factors. Some studies, for example, suggest that women have better innate immunity than men (hence, in the case of covid-19, women had a lower incidence of infection and a lower rate of serious illness and/or mortality). It has also been observed that some genetic peculiarities related to this first barrier of the immune system can reduce the risk of covid-19 infection (as in the case, for example, of the interferon production: proteins responsible for activating antiviral defenses).