A growing body of evidence suggests that adult biological males are nearly twice as likely to die from severe COVID-19 as females, write authors in this Perspective. And while sex differences are closely intertwined with differences in gender roles socially and with behavioral factors that likely influence COVID-19 infection and outcome, the global pattern suggests that there may also be biological factors that underlie the apparent male sex bias for severe disease and death from COVID-19. In their Perspective, Takehiro Takahashi and Akiko Iwasaki explore various ways antiviral immune responses differ between the biological sexes, with implications for COVID-19 severity. Some examples include differences in immune-related genes encoded on the sex chromosomes and also the protective role of the female sex hormone estrogen, which could have antiviral implications for those receiving hormone therapies. However, despite the emerging understanding of the role of biological sex differences in immune responses to COVID-19, Takahashi and Iwasaki note that sex is not binary. They highlight that little is known regarding antiviral responses for individuals with disorders of sex development (DSD), where anatomical sex is atypical, or for transgender individuals, including those undergoing gender reassignment hormone therapies. According to the authors, it is possible that DSD and transgender individuals may mount distinct immune responses to viral infection in general, which needs to be considered to fully understand the risks of SARS-CoV-2 infection and to inform vaccination efforts. "It is important that studies of COVID-19 patients report results in a sex-disaggregated manner, not only to elucidate differential disease pathogens, but also to enable a deeper understanding of this disease and the eventual development of better treatment and preventative strategies," write Takahashi and Iwasaki.
###
Journal
Science