, raising questions about potential consequences for reproductive health among those infected.
The study, published online Feb. 8 on the preprint server MedRxiv, found that “patients who become critically ill exhibit severe damages and may harbor the active virus in testes,” which can “serve as a viral sanctuary.”
Guilherme M.J. Costa, PhD, a professor at Universidade Federal de Minas Gerais, Belo Horizonte, Brazil, led the study, which has not yet been peer-reviewed.
“A critical point of this article is that the virus was active in the patient’s testis after a long period of infection, indicating that the testis is able to maintain the viable virus for extended periods. It happens for many kinds of viruses in this genital organ,” Dr. Costa said in an interview.
Brian Keith McNeil, MD, vice-chair, department of urology at SUNY Downstate Health Sciences University in New York, told this news organization that the topic of COVID-19 and fertility has been discussed but data are sparse on the subject.
“The question this raises is whether or not COVID can live in the testes, and based on this it seems it can,” he said, adding that it also raises the question of whether COVID-19 could be transmitted through semen. “It leads one to wonder whether this could have a long-term impact on fertility in men and women.”
The authors wrote that deep testicular evaluation of patients who have been infected with COVID-19 is critical because the testes have one of the highest expressions of angiotensin converting enzyme 2 (ACE2) receptors, which play a large role in entrance of the virus into cells.
“A direct influence of SARS-CoV-2 in testicular cells might deregulate ACE2, elevating the levels of angiotensin II, a potent pro-inflammatory and angiogenic peptide,” the authors wrote.
Sperm-producing cells infected
In 2021, the researchers enrolled 11 male patients deceased from COVID-19 complications; none had received a vaccine. Infection was confirmed by SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR) performed during their hospital stay. All 11 patients were admitted to the intensive care unit with severe pulmonary symptoms.
All but one of the patients had children and none had scrotal symptoms or complaints during their time in the hospital. Their clinical histories revealed no testicular disorders.
Dr. Costa said they found that detecting SARS-CoV-2 mRNA in testes is difficult in a conventional RT-PCR test.
Therefore, “We modified the protocol of the RT-PCR and used nanosensors. We observed that SARS-CoV-2 has a huge tropism for the testes in this context,” he said.
He said the team performed stainings and “discovered that macrophages and germ cells are highly infected.”
That’s important, he said, because an immune cell, which is supposed to fight the virus, is infected in the tissue. Also, the germ cell, responsible for sperm production, is infected.
“This reopens the worries about the presence of SARS-CoV-2 in semen, as other authors mentioned,” he said.
The team also found that the testes are a good place for viral replication.