The most common advice people are hearing during the coronavirus outbreak is to stay 6 feet apart. But in an era of safe physical distancing many are wondering if it’s also possible to have safe sex. The virus responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been detected in stool, gastrointestinal tract, saliva, and urine samples. However, little is known about SARS-CoV-2 in semen. The researchers said the novel coronavirus requires ACE2 and TMPRSS2 to enter human body cells. ACE2 is a receptor protein to which Sars-CoV-2 anchors itself. Thereafter, TMPRSS2 activates entry of the virus into a body cell.
SARS-CoV-2 can be present in the semen of patients with COVID-19, and SARS-CoV-2 may still be detected in the semen of recovering patients. Owing to the imperfect blood testes/deferens/epididymis barriers, SARS-CoV-2 might be seeded to the male reproductive tract, especially in the presence of systemic local inflammation. ACE2 and TNPRSS2 are two proteins that the novel coronavirus uses to enter a person’s body cells. External body organs with a high density of these proteins are particularly vulnerable to the novel coronavirus, and thus can become entry gates for Covid-19.
Even if the virus cannot replicate in the male reproductive system, it may persist, possibly resulting from the privileged immunity of testes. So far, researchers have found 27 viruses associated with viremia in human semen. But the presence of viruses in semen may be more common than currently understood, and traditional non–sexually transmitted viruses should not be assumed to be totally absent in genital secretions. If a disease like Covid-19 were sexually transmittable, that would have major implications for disease prevention and could have serious consequences for a man’s long-term reproductive health. The fact that the novel coronavirus’ genetic material is found in the semen of male patients is an important finding that will need follow-up study. ACE2-mediated viral entry of SARS-CoV-2 into target host cells is unlikely to occur within the human testicle based on ACE2 and TMPRSS2 expression. The long-term effects of SARS-CoV-2 on male reproductive function remain unknown. Studies on viral detection and semen persistence are beneficial to clinical practice and public health, especially concerning viruses that could cause high mortality or morbidity, such as SARS-CoV-2. The exact mechanisms by which SARS-CoV-2 interacts with the gastrointestinal tract is unknown. However, angiotensin-converting enzyme II (ACE2) seems to be used by the virus as a receptor to enter cells.
ACE2 messenger RNA is highly expressed in the gastrointestinal system, and immunofluorescent data show that the ACE2 protein is abundantly present in the glandular cells of rectal epithelia. In addition, SARS-CoV-2 RNA identification and intracellular staining of viral nucleocapsid protein in rectal epithelia demonstrated that the virus infects such epithelial cells
However, the study also raises questions: It doesn’t explain how much viral load was present in the sperm, nor does it examine whether or not the virus could be transmitted through sexual activity. The recognition of viral RNA from faeces indicates that virions are secreted from the virus-infected cells.
Moreover, SARS-CoV-2 can also be transmitted through the saliva, and ACE2 has been detected on the mucosa of oral cavity, which is rich in epithelial cells. Therefore, if saliva and feces are both capable of carrying the virus and ACE2 is expressed both in the glandular cells of rectal epithelia and oral mucosa, how can we be sure that sexual intercourse does not represent another way of contagion?
While the U.S. Centers for Disease Control and Prevention and World Health Organization, two authorities on containing the virus, have abstained from offering explicit advice on how to handle intimacy during the pandemic, other sources have offered some basic protective measures people can take when they’re feeling the urge.