also discovered that affects the penis. An penile tissue from two ing penile implants irus was present seven to nine months after their COVID19 diagnosis. Both men had developed severe erectile dysfunction, probably because the infection caused reduced blood supply to the penis.

Notably, one of the men had only mild COVID-19 symptoms. The other had been hospitalized. This suggests that even those with a relatively light case of the virus can experience severe erectile dysfunction after recovery.

These findings are not entirely surprising. After all, scientists know other viruses invade the testicles and affect sperm production and fertility.

One example: Investigators studying testes tissues from six patients who died from the 2006 SARS-CoV virus found all of them had widespread cell destruction, with few to no sperm.

It is also known that mumps and Zika viruses can enter the testicles and cause inflammation. Up to 20% of men infected with these viruses will have impaired sperm production.

A new study on vaccine safety

Additional research by my team brought welcome news. A study of 45 men showed the Pfizer and Moderna mRNA vaccines appear safe for the male reproductive system.This, then, is another reason to get the vaccinations – to preserve male fertility and sexual function.

Granted, the research is only a first step on how COVID-19 might affect male sexual health; the samples were small. Studies should continue.

Still, for men who have had COVID-19 and then experienced testicular pain, it is reasonable to consider that the virus has invaded testes tissue. Erectile dysfunction can be the result. Those men should see a urologist.

I also believe the research presents an urgent public health message to the U.S. regarding the COVID-19 vaccines.

For the millions of American men who remain unvaccinated, you may want to again consider the consequences if and when this highly aggressive virus finds you.

One reason for vaccine hesitancy is the perception among many that COVID-19 shots might affect male fertility. Our research shows the opposite. There is no evidence the vaccine harms a man’s reproductive system. But ignoring the vaccine and contracting COVID-19 very well could.