Scientists have found evidence that hint at the possibility of link between persistence of zika virus in male reproductive organs and its role in male infertility.
Scientists have also found that if the zika virus persists in male reproductive organ, it could even be sexually transmitted. Researchers have based their findings on a study that found that the infection reduces the size of testes in mice up to 21 days after infection. The study is published in the journal Science Advances.
There have been evidence that point to persistence of the zika virus in semen of humans for months after infection; however, there have been no studies to understand how the virus affected the testes and how it could affect fertility of males and whether it could be sexually transmitted.
Erol Fikrig, Professor of Medicine at Yale University in the US, and team carried out study on mouse model by infecting mice with a non-lethal strain of the Zika virus. The mice used in this study were genetically modified so the researchers could observe viral replication over an extended period of time.
Evidence indicated that the virus continued to replicate in testicular cells even after it was cleared from the blood. They also discovered that 21 days after infection, the testes of infected mice were significantly smaller than those of control mice.
“This study shows how the Zika virus replicates in and damages testes,” said first author Ryuta Uraki.
The persistence of the virus in a storage compartment known as the epididymis, which conveys sperm from the testicle to the urethra, is consistent with the reported cases of male-to-female sexual transmission, he said.
The finding of reduced testicular size – known as testicular atrophy – indicates a potential long-term effect on male fertility.
“These results suggest that infection can cause reproductive deficiency in males,” Uraki noted.
The study results, which extend recent findings by other researchers, underscore the critical need for the development of a vaccine, as well as antiviral therapies, to combat Zika infection, the researchers said.