By now, most of us are pretty familiar with the effects the Zika virus can have on pregnant women and their unborn children: Those babies can be born with horrible developmental issues and birth defects.
In the study, researchers injected mice with the virus. And in three weeks' time, Zika made its way to the mice's balls, damaged the inner workings of the balls and shrunk them down to one-tenth of their actual size.
That might not sound like a big deal, but it is. Size matters here, people. When testicles are damaged, they're unable to produce testosterone and sperm at a normal rate.
Sure enough, the mice in the study could only produce 10 times fewer sperm than they normally would've been able to six weeks earlier. Those mice were also four times less likely to get female mice pregnant.
Kelle Moley, MD, fertility specialist and co-senior author of the study, spoke to the magnitude of the virus and its effects on male mice, which could be applied to men's health, as well: “This is the only virus I know of that causes such severe symptoms of infertility.”
Still, there's more research to be done about whether testicles of the mice infected with Zika can recover.
Michael Diamond, PhD, MD, another co-senior author of the study, isn't very hopeful: “We don't know for certain if the damage is irreversible, but I expect so, because the cells that hold the internal structure in place have been infected and destroyed.”