Researchers from the University of Miami, Florida, found impaired sperm function in testis tissues of three out of six men who died of COVID-19 infection. SARS-CoV-2, the virus which cases COVID-19, was also present in the testis tissue of one man who had recovered from the virus.
'These findings could be the first step in discovering COVID-19's potential impact on male fertility and whether the virus can be sexually transmitted,' said senior author and director of reproductive urology Dr Ranjith Ramasamy.
COVID-19 had been suggested to harm sperm production, reducing fertility in men who had recovered from moderate or severe viral symptoms (see BioNews 1067). Considering that testes are responsible for sperm and testosterone production, testis tissue represents a target for viral infection that could explain the reduction in male fertility.
The study, published in the World Journal of Men's Health, compared the testis tissue from autopsies of six men who died of COVID-19 infection. Tissue from the COVID-19 positive postmortem cases was analysed using electron microscopy.
This study disagrees with previous findings that suggested that COVID-19 damaged sperm-making cells without infecting the testes (see BioNews 1050).
Interestingly, COVID-19 presence was also identified in the testis tissue of a patient who underwent a testis biopsy for infertility and had previously recovered from the virus. 'This is the first published research to report on the case of a live patient to demonstrate the presence of COVID-19 in testis tissue of a patient who recovered from the virus. The finding is novel, remarkable, and certainly worthy of further exploration.' said Dr Ramasamy.
Questions remain around the threshold of viral load in the testes required for the virus to be detected in semen, as well as the viral load needed in the semen to be sexually transmitted.
'More studies are needed to evaluate exactly how testis tissue responds to the virus and what that might mean to male fertility and sexual transmission. This study is the first step in that process and opens the door to important research to pursue.' said Dr Ramasamy.