Why are women better at fighting COVID-19 than men?

The 2019 coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), has placed an unprecedented burden on global healthcare systems, To date, more than 425 million people have been infected and 5.8 million have died (March 2022). Gender differences in the severity of the disease have been observed worldwide, with women being less infected than men.

Why are men more susceptible to severe COVID-19 than women?

There are a number of genetic, immunological, and lifestyle or behavioral factors that may increase a man’s risk of disease severity.

Genetic susceptibility

Sars-cov-2 infection is triggered by viral spike proteins binding to the host cell receptor angiotensin-converting enzyme 2 (ACE2) present on respiratory epithelial cells. This is followed by the fusion of the viral envelope with the host cell membrane and the transport of viral RNA into the host cell. Single-cell RNA sequencing analysis showed that ACE2 expression was significantly higher in Asian males than in Asian females. Thus, the gene expression and cell distribution patterns of ACE2 make men more susceptible to SARS-COV-2 infection than women.

Immune susceptibility

In general, women have a higher immune response to viral or bacterial infections than men. This may be because women have two X chromosomes, rather than the one observed in men.

Lifestyle factors

Globally, relatively high rates of smoking and alcohol use are observed among men. Differences in these lifestyle behaviours between males and females may be the underlying cause of gender-based COVID-19 susceptibility. In addition, men are more likely than women to engage in high-risk behaviors, further increasing their chances of contracting COVID-19.