There needs to be a broader study of how biological sex differences affect outcomes with COVID-19, researchers argue in a recent paper.
Though it’s still unclear exactly why, what is clear is that men are suffering worse fates than women when it comes to COVID-19, regardless of geography or age.
A variety of data from outbreaks across the world has established this, and researchers like Johns Hopkins University biologist Sabra Klein are trying to understand more.
Last month, Klein contributed to a paper published in the Journal of Critical Investigations, which calls for a study of sex differences in COVID-19 outcomes. The authors argue that these differences should be a significant consideration for developing effective treatments and vaccines.
Here, Klein explains what the scientific community knows so far about the different outcomes between men and women who contract COVID-19:
Because these findings are cutting across social and cultural boundaries, that strongly suggests the biological difference between males and females is contributing. That likely doesn’t tell the full story, however—social and lifestyle factors may certainly be influencing the trends, but we need to understand more.
A sex difference in immune responses that control and clear SARS-CoV-2 suggests there 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.
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.
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.
Vaccines are just one arm of how we’re addressing protections from COVID-19, however. Another is therapeutics. We have data from the past showing more adverse reactions for women than men with antiviral drugs, and it’s important to be aware of that. We don’t want the reaction to the drug to be worse than the condition it’s trying to treat.
This article was originally published by Johns Hopkins University. Republished via Futurity.org under Creative Commons License 4.0.