Go to Content Go to Navigation Go to Navigation Go to Site Search Homepage

Pictured above: Adenovirus. From https://phil.cdc.gov/phil/details.asp?pid=10010

You might have read the headlines earlier this month that the virus that causes COVID-19 has been found in semen. Is that true — and if it is, does that mean COVID-19 can be transmitted sexually?

The short answers to those questions are yes, and we don’t know yet.

Several viruses that aren’t thought of as sexually transmitted can be found in semen.

JAMA recently published a short article about a small study conducted in China. The authors took semen from 38 people who were either recovered from COVID-19 or still in the throes of infection. Of those 38 people, six were found to have the novel coronavirus hiding out in their semen — adding semen to the list of bodily fluids in which the virus can lurk, including saliva, urine, and feces.

This study is too limited to make sweeping generalizations, but it does seem to show that it’s possible — though perhaps not overwhelmingly likely — for someone suffering from COVID-19 to be none the wiser as the virus wends its way to the body’s southern hemisphere, where it can hang out in the testes. Plus, the virus was detected not just in people with active disease, but also in people who had recovered, raising the possibility that someone can carry the virus below the belt even after symptoms are gone.

The authors merely report their findings — they don’t make any further claims, and remind readers that further study is needed to show whether the coronavirus can be transmitted sexually. For now, we don’t know if the coronaviruses found in sperm are capable of causing an infection, or if they are just harmless viral fragments. Since the coronavirus primarily affects the respiratory tract, sexual partners are much more likely to transmit it through other close contact — not just kissing, but also by more mundane activities like touching contaminated surfaces or breathing in their sweetie’s airborne saliva.

Findings like this might, however, inspire more people to use condoms during oral sex to prevent the virus from invading the respiratory system.

The Novel Coronavirus: Not the Only One

The virus that causes COVID-19 isn’t the only one that can be found in semen. There are many other viruses that can hunker down in the testes — including a few that aren’t considered STDs in the classical sense. And the novel coronavirus isn’t the only respiratory virus that can find itself in semen — it’s also possible for a penis to have a cold. Adenoviruses are a class of viruses most famous for causing the common cold, bronchitis, and pinkeye. But certain strains of adenovirus can also cause urethritis, or inflammation of the urethra, which can cause painful urination.

Researchers have demonstrated that receiving oral sex increases urethritis risk for someone with a penis, as saliva and other oral secretions contain high viral concentrations. There’s also some evidence that sexually transmitted adenovirus could be seasonal, with cases spiking in the autumn.

Or you might remember Zika virus, the mosquito-borne pathogen that has caused so many tragic birth defects. In 2016, sexually transmitted Zika virus made headlines, but it had already been documented eight years earlier, when a married couple who published their experience in a scientific paper thought they could share their STD status in relative obscurity. Despite referring to themselves as “Patient 1” and “Patient 3,” a science reporter quickly figured it out and (with their permission) revealed their identities in a 2011 article.

It’s thought that Zika virus can find refuge from the immune system in the testicles, which are a difficult location for a virus to enter — but, by the same principle, entry is also difficult for immune cells, allowing a virus to replicate in relative peace. Maybe the novel coronavirus is using the same stealthy strategy!

Unlike gonorrhea, chlamydia, and other bacterial infections, coronavirus, Zika virus, and adenovirus infections cannot be cured with antibiotics. The best way for sexually active people to avoid STDs is to use condoms and dental dams consistently and correctly, be screened for STDs before initiating sexual activity, and limit sexual partners. Planned Parenthood health centers can diagnose and treat STDs. For more information on preventing COVID-19, visit the Centers for Disease Control and Prevention‘s website.

Tags: condoms, oral sex, sperm, semen, sexually transmitted infections, STIs, kissing, saliva, sexual health, STD Awareness, coronavirus, covid19, covid-19, adenovirus

Anna C.

Anna first volunteered for Planned Parenthood as a high school student in the 1990s. Since then, she has received a bachelor’s degree from UC Berkeley and a master's degree in epidemiology from the University of Arizona. As an ode to her fascination with microbes, she writes the monthly STD Awareness series, as well as other pieces focusing on health and medicine.