Why do men suffer more severe COVID-19 and a higher risk of death? Do we know anything new?

Biology/Immunity Clinical Symptoms

A: Women may mount a stronger T cell response to SARS-CoV-2 infection, according to a recent paper in Nature from the lab of immunologist Dr. Akiko Iwasaki.

In the study, researchers collected blood, saliva and other samples from 17 men and 22 women aged 60+ admitted to the hospital after a positive COVID-19 test and analyzed their immune response to the infection. None of the patients were taking immunomodulating drugs such as steroids at baseline.

Men had much weaker activation of T cells, and those with the lowest T cell response became the sickest. The T cell response became progressively worse with older age in men, while even very old women were able to mount a robust response.

Men also produced more proinflammatory cytokines at baseline compared to women, and women who did have high levels of proinflammatory cytokines developed worse disease.
While the study was small and focused on a limited age range, it highlights potential sex differences in immune response that could be important for therapy and vaccine development. For example, it’s possible that older men may need a different vaccine dose to illicit a robust immune response.

TL;DR: Sex matters in how we should think about COVID-19 therapy and prevention.

Ladies, the guys can’t help their weak T cells…keep looking out for all our beloved Nerdy Guys out there!

The Nerdy Girls
*Note on death figure from the ONS: while there are more female deaths in the oldest age group, this is because women make up a higher % of the population at the oldest ages (69% female among 90+). The risk of death is still higher for men at the oldest ages.

Recent article with further summary of the paper

Link to the academic paper in Nature

Link to original FB post