FRI, JUN 19 2020-theG&BJournal- ‘’Because women typically have a more rapid and robust immune response to viruses than men, this may be one factor contributing to female-biased protection against SARS-CoV-2, the virus that causes COVID-19,’’ Johns Hopkins biologist Sabra Klein, explains.
The Hub, Johns Hopkins news center, reached out to Klein for insights on what the scientific community knows so far about the different outcomes between men and women who contract COVID-19.
There are data, she says, from early outbreaks in Wuhan, China, for example, that show women clear the virus more quickly than men.
‘’A sex difference in immune responses that control and clear SARS-CoV-2 suggests there’s a difference between sexes affecting immunity. We have data for other viruses illustrating that sex differences in immunity are caused by genetic as well as hormonal differences between women and men. For example, in females, hormones such as estrogen and progesterone may be protective against the virus, and it’s possible testosterone does the opposite for men.’’
Men out number women when it comes to COVID-19 infection in Nigeria, regardless of geography or age. A variety of data from outbreaks across the world also has established this fact. In Nigeria, the Centre for Disease Control (NCDC) data reveal the percentage of men exposed to coronavirus is as high as 65%.
Scientists are also looking into the role of the ACE-2 receptor, which is found on the cells lining the lung and airways and is used by the SARS-CoV-2 virus to enter cells.
‘’From what we know about this receptor, from other conditions such as hypertension and kidney disease, ACE-2 expression is greater in males than in females. We also know from work in the kidneys that estrogen downregulates the expression of ACE-2, which could be a plausible biological explanation for reduced severity of the virus in women,” Klein said.
Klein cited ‘’a very large JAMA study on cases in New York City’’ which looked at ages 30 through 90, and found that males were significantly more likely to be hospitalized or die regardless of age.
‘’Another study in The Lancet examining ages 20 upwards in European countries also shows this trend across ages. What we’re seeing in ages 60 years and older is that this is where we find the most severe outcomes of death.’’
She suggests that biological differences are only part of the story of what make men and women different. ‘’It also has to do with our behavior and even the social and cultural norms that define our roles and responsibilities.’’
‘’For example, females may be more likely to be frontline workers, which could create more risks for exposure. In terms of lifestyle, men tend to be more likely to be smokers, which is a risk factor, and they’re less likely to seek out medical care when there’s a problem. And with COVID-19, if men are less likely to engage in behaviors like mask-wearing and hand-washing, that may increase risks,’’ she said.
According to Klein, ‘’there are also underlying conditions such as hypertension, heart disease, and diabetes, which men are statistically more likely to have and some of which can be attributed to lifestyle factors, that also amplify risks with COVID-19.’’