Where does SARS-CoV-2 travel in the body and cause infection?

It may seem like a silly question after more than two years of living with the coronavirus, but there are still questions about where the virus takes root and causes disease.

In the rush to understand a disease that was killing people around the world, doctors were seeing symptoms that may or may not be signs of COVID-19.

An example of this was “COVID toes, red or purple toes that were sore and swollen and unpleasant to look at.

They have been the subject of many titles. Some doctors said that it was not uncommon for sick and run-down people to develop these kinds of “rashes.”

A whole phenomenon took off, despite the fact that many people with “COVID toes” had in fact not been tested for the virus.

Last week, a new study suggested that ‘COVID toes’ could be nothing more than frostbite, ‘from people walking barefoot at home during lockdown’.

However, this remains an open question.

Erectile dysfunction and fertility

A year ago, two tricky questions emerged from the pandemic and were the subject of much scrutiny:

Can the SARS-CoV-2 virus infect semen and spread through sexual intercourse? Probably not, but the jury is still out.

And does COVID-19 reduce fertility in men? Yes, it is possible, and more.

Some men who are sick with COVID-19 have been known to show a reduction in sperm count and quality, and a subsequent decrease in fertility.

It also appeared that some men suffered from testicular pain and erectile dysfunction.

The question became: were these problems caused by fever and inflammation, or were they the direct result of a viral infection.

The latter was possible. It can occur in adults and teenagers who get mumps.

But where was the proof?

Researchers from Northwestern Medicine have settled the argument – after going on a fishing expedition and apparently surprised themselves.

Using a PET scan “specifically designed to reveal sites of infection spreading over time in a whole-body scanner”, the scientists went in search of the parts of the body that harbored the coronavirus.

Scientists say they ‘didn’t know what they would find, but they expected to see the virus in the lungs and high up in the nose near the brain because people were experiencing loss of taste and smell’ .

The study, which used rhesus macaques infected with SARS-CoV-2 – as a reliable surrogate for the human body – found that the prostate, penis, testicles and associated blood vessels were all infected with the virus.

Lead researcher Dr. Thomas Hope, professor of cell and developmental biology at Northwestern’s Feinberg School of Medicine, said:

“The signal that jumped out at us was full spread through the male genital tract. We didn’t know we would find it there.

What does it mean?

Dr. Hope said these results indicate “that testicular pain, erectile dysfunction, hypogonadism, reduced sperm count and quality, and decreased fertility associated with SARS-CoV- 2 are a direct consequence of the infection of the cells of the male reproductive system and not indirect. mechanisms such as fever and inflammation”.

Evidence that SARS-CoV-2 infection can negatively impact male sexual health and fertility is growing daily. But scientists didn’t know the reason and wondered if the cause was fever and inflammation.

Dr Hope said viruses such as mumps, Ebola, Zika, SARS-COV-1 and others were also known to infect male genital tract tissue and negatively impact fertility.

“Mumps infection is well known to potentially cause male infertility,” he said.

Another good reason to get vaccinated

Dr Hope said that even if only a small percentage of the male population were infected, “that represents millions of men who could suffer a negative impact on their sexual health and fertility”.

Clinical studies suggest that 10-20% of men infected with SARS-CoV-2 experience symptoms related to male genital tract dysfunction.

Dr Hope said this suggests that “tens of millions of men who have been infected with SARS-CoV-2, especially those who have had severe COVID-19, should assess their sexual health and fertility to determine whether additional therapies might prevent or alleviate future problems.” . .

He said the potential impact of SARS-CoV-2 infection on sexual and reproductive health should be part of everyone’s decision to get vaccinated.

The new study is published as a preprint on bioRxiv, which means it should be considered preliminary research until it is published in a peer-reviewed journal.