Мen аре more likely than women to contract the COVID-19 virus and to suffer severe or critical complications,  researchers claim.

In Italy, an analysis of more than 127,700 COVID-19 cases found that 52.9% of all infected people were men and 47.1% women. Among Italy’s first 14,860 deaths, almost 68% were men, Reuters reports.

A Chinese Center for Disease Control and Prevention report found that in a dataset of 44,672 confirmed cases, there was a 1.1% higher COVID-19 fatality rate in men compared to women.

Health specialists point to a number of possible factors. These include both behavioural and biological risks.

Unhealthy habits, smoking, and their impact

Experts say one influence may be that men, in general, don’t look after their bodies as well as women do - with lower levels of handwashing and hygiene, and higher levels of smoking, alcohol use, obesity and other unhealthy behaviours.

In many countries, smoking rates are higher among men than women, and smoking is a known risk factor for many other life-threatening conditions such as heart disease, high blood pressure, lung disease and cancer.

Women’s “aggressive” immune response

Research shows that immune response throughout life - to everything from vaccines and infections to autoimmune diseases - is typically more aggressive in women than in men. With COVID-19, a respiratory disease caused by a coronavirus, this may be a particularly significant factor.

Philip Goulder, a professor of immunology at Oxford University, says several factors contribute to women having more aggressive immune systems, including that females have two X chromosomes compared to one in males, and that a number of critical immune genes are found on the X chromosome.

In particular, the protein by which viruses such as coronavirus are sensed is encoded on the X chromosome,” Goulder said. That means this protein is expressed at twice the dose on many immune cells in women compared to men, which in turn could well be boosting females’ ability to ward off COVID-19.