ABSTRACT
A unique opportunity to conduct a longitudinal analysis of semen quality in a male subject immediately before, during and after COVID-19 infection, has revealed new insights into the impact of this virus on male reproductive function. A moderate COVID infection that did not require hospitalization resulted in a state of azoospermia that persisted for 4 weeks. Given that the duration of spermatogenesis and epididymal sperm maturation in the human is 78 days, we calculate that a viral attack on the germ line was initiated at or before the patient was symptomatic and may have been signalled by a sudden reduction in sperm count and motility, several weeks earlier. Before the virus had been fully cleared, reinitiation of spermatogenesis occurred as evidenced by spermatozoa reappearing in the ejaculate exhibiting high levels of motility but significant levels of oxidative DNA damage as measured by a modified 8-OHdG assay protocol. These unique data indicate that even a moderate COVID-19 infection is capable of rapidly inducing a state of azoospermia that rapidly reverses as the infection wanes.
ABSTRACT
Viral infections have haunted humankind since times immemorial. Overpopulation, globalization, and extensive deforestation have created an ideal environment for a viral spread with unknown and multiple shedding routes. Many viruses can infect the male reproductive tract, with potential adverse consequences to male reproductive health, including infertility and cancer. Moreover, some genital tract viral infections can be sexually transmitted, potentially impacting the resulting offspring's health. We have summarized the evidence concerning the presence and adverse effects of the relevant viruses on the reproductive tract (mumps virus, human immunodeficiency virus, herpes virus, human papillomavirus, hepatitis B and C viruses, Ebola virus, Zika virus, influenza virus, and coronaviruses), their routes of infection, target organs and cells, prevalence and pattern of virus shedding in semen, as well as diagnosis/testing and treatment strategies. The pathophysiological understanding in the male genital tract is essential to assess its clinical impact on male reproductive health and guide future research.