A recent study from Northwestern University found that COVID-19 can potentially invade cells in the penis. The research found that a COVID infection can cause testicular soreness, diminished sperm count, and erectile dysfunction.

“These results indicate that the testicular pain, erectile dysfunction, hypogonadism, reduced sperm count and quality, and decreased fertility associated with SARS-CoV-2 infection are a direct consequence of infection of cells of the male reproductive tract and not indirect mechanisms such as fever and inflammation,” said the study's leader Dr. Thomas Hope, a professor of cell and developmental biology at Northwestern University Feinberg School of Medicine.

“The signal that jumped out at us was the complete spread through the male genital tract… We had no idea we would find it there.”

A study published in January in the American Journal of Epidemiology found evidence that the COVID-19 can temporarily hinder fertility levels in men. The vaccine seemed to have no effect on fertility levels in men or women, however.

Another study, published in September 2021, concluded that there was "emerging evidence that COVID-19 has a uniquely harmful impact on men's health and erectile function through biological, mental health, and healthcare access mechanisms."

Erectile dysfunction is part of a long list of potential long-term side effects of COVID infection. Research from University College London in July 2021 found that people with "long COVID" identified more than 200 symptoms.

Dr. Hope advises everyone to get vaccinated against COVID-19 and adds that mumps, Ebola, Zika, among other viruses can also invade the male genital tract.

Dr. Hope will also conduct research into whether COVID-19 can affect the female reproductive system.