A team of US scientists believe they have discovered a new sexually transmitted disease that, if left untreated, could lead to fatal liver failure and infertility.
Researchers at Ohio State University have discovered that the hepatitis E virus is present in semen samples, suggesting it can be transmitted through sex.
It used to be assumed that the virus, which does not always cause complaints, only spreads through contaminated water.
The experts found that the sperm cells infected with the virus were less mobile and showed genetic defects, which they said could provide evidence of the virus’s role in cases of male infertility.
Hepatitis E virus was found in semen of pigs, indicating that the virus is both sexually transmitted and linked to male infertility
The current study was conducted in pigs, whose reproductive systems are reportedly very similar to those of humans.
The scientists are now ‘urging’ that men with infertility be screened for hepatitis E, which could be a ‘potential cause’ of their problems.
Worldwide, approximately 20 million cases of the hepatitis E virus (HEV) occur annually, of which only three million are symptomatic. The infections are more common in developing countries without clean water because viral cells in feces enter the water supply and infect individuals when they drink it.
Other types of hepatitis, including A, B, C and D, are all caused by different viruses and are transmitted in different ways, for example through blood or sexual fluids, as well as by sharing needles.
Hepatitis E causes inflammation in the liver, which can cause people to develop a yellowish tinge to the skin and eyes, known as jaundice. It can also cause abdominal pain, fever, weight loss, dark urine and fatigue. Most people recover completely within four to six weeks without permanent liver damage.
The virus not only increases the risk of acute liver failure, but is also linked to male fertility problems and neurological disorders.
While most patients recover on their own by rehydrating and replenishing electrolytes and taking medications to address symptoms such as nausea, the prognosis for pregnant women is worse.
In the new study, researchers at Ohio State University isolated the virus particles from semen of infected pigs.
The researchers injected pigs with the virus and found that it circulated in the blood and was excreted in feces.
Eighty-four days after the injection, researchers found HEV on the heads of pig sperm cells. About 19 percent of the sperm cells contained particles of the virus, which were contagious, meaning the virus could have been transmitted to another pig.
Dr. Kush Yadav, an Ohio State researcher who led the study, said, “We can’t say that they [the viral cells] are on the outside or inside of the sperm cells.’
To investigate semen quality further, researchers analyzed 200 sperm cells to compare their movement and shape.
Sperm infected with the virus strain that can infect humans showed a 14 percent reduced ability to move through the reproductive tract, a measure called motility, compared to that of uninfected pigs.
In infected pigs, more sperm were completely immobile compared to the uninfected pigs.
In addition, semen from HEV-infected pigs was more likely to have abnormally shaped and large heads and tails.
In humans, these morphological changes are known to reduce a male’s ability to impregnate a partner, as well as increase the risk of causing DNA changes in a fetus, resulting in birth defects.
That said, they can’t say for sure whether these changes translate directly into fertility problems.
While the findings, published in the journal PLoS pathogensare convincing, many important unanswered questions remain about the ability of HEV to be transmitted during sex.
Further research is needed to understand how sperm cells become infected with HEV, how long the virus persists in the testicles, how long the virus can be shed from sperm cells, and whether sexual intercourse can lead to systemic infection in partners.
The country is facing a long-term STD crisis.
In 2021, gonorrhea reached its highest level since 1991 and syphilis since 1990.
Meanwhile, chlamydia rates have almost doubled since twenty years ago.
STDs do not always have symptoms and, if left undiagnosed and untreated, can have serious health consequences.
Syphilis is one of the most threatening diseases, as it can be a direct cause of death (while human papillomavirus, HIV and hepatitis more often cause death due to secondary conditions).
This year, the number of syphilis cases is at its highest level since the 1950s. An annual report of the CDC showed that 207,300 cases of the STD – which can cause sores on the genitals and mouth – were diagnosed nationwide in 2022, the latest year available.
That represented an increase of 17 percent in one year and an increase of 83 percent compared to five years ago.
Without treatment, patients with the ulcers are at risk of the disease spreading to their brain and spinal cord, which can lead to vision loss, sensory problems, psychosis, paralysis or stroke.
Experts have pointed to a host of reasons for the rise in STD rates, including a decline in condom use, fewer local sexual health clinics and rampant drug use.
Hepatitis E typically spreads through contact with feces, such as touching fecal particles and putting your hands to your mouth, drinking unclean water, and eating uncooked pork.
The risk of dying from a hepatitis E infection is low, less than four percent.
However, the risk is significantly higher in pregnant women.
About 10 to 30 percent of pregnant women infected with HEV die in their third trimester. Pregnancy changes the immune system, making the mother’s body less able to fight infections.