A team of American scientists believe they have discovered a new sexually transmitted disease that can cause fatal liver failure and infertility if left untreated.
Researchers at Ohio State University have discovered the hepatitis E virus in sperm samples, suggesting it can be transmitted through sex.
It was previously believed that the virus, which does not always cause symptoms, only spreads through contaminated water.
The experts found that sperm infected with the virus were less motile and had genetic defects, which they say may provide evidence of the virus’s role in cases of male infertility.
The hepatitis E virus was found in the sperm of pigs, suggesting that the virus can be transmitted sexually and be linked to male infertility.
The current study was conducted in pigs, whose reproductive systems are said to be very similar to those of humans.
Scientists are now “pushing” for men with infertility to be tested for hepatitis E, which may be a “potential cause” of their problems.
There are around 20 million cases of hepatitis E virus (HEV) worldwide each year, and only three million are symptomatic. Infections are more common in developing countries without clean water, as viral cells from fecal matter enter the water supply and infect people when they drink it.
Other types of hepatitis, including A, B, C, and D, are caused by different viruses and are transmitted in different ways, such as through blood or sexual fluids, as well as through sharing needles.
Hepatitis E causes inflammation in the liver, which can give people a yellowish tint to the skin and eyes, known as jaundice. Abdominal pain, fever, weight loss, dark urine, and fatigue may also occur. Most people recover completely without lasting liver damage within four to six weeks.
In addition to increasing the risk of acute liver failure, the virus is also linked to fertility problems in men and neurological disorders.
While most patients recover on their own by rehydrating and replenishing electrolytes and taking medications to treat symptoms such as nausea, the prognosis is worse for pregnant women.
In the new study, researchers at Ohio State University isolated virus particles from the sperm of infected pigs.
The researchers injected the pigs with the virus and found that it circulated in the blood and was shed in feces.
Eighty-four days after the injection, the researchers found HEV in the pigs’ sperm heads. About 19 percent of the sperm contained virus particles, which were infectious, 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 (the viral cells) are located outside or inside the sperm.”
To take a closer look at sperm quality, the researchers analyzed 200 sperm to compare their movement and shape.
Sperm infected with the strain of the virus 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.
More sperm in infected pigs were completely immotile compared to uninfected pigs.
Additionally, sperm from HEV-infected pigs were more likely to have abnormally shaped and sized heads and tails.
In humans, these morphological changes are known to decrease a man’s ability to impregnate his partner, as well as an increased risk of causing changes to the DNA of the fetus, resulting in birth defects.
That said, they can’t say for sure whether these changes directly translate to fertility problems.
Although the findings, published in the journal More pathogensare compelling, many important questions remain unanswered about HEV’s ability to be transmitted during sexual intercourse.
More research is needed to understand how sperm become infected with HEV, how long the virus persists in the testicles, how long the virus can be cleared from sperm, and whether sexual intercourse can lead to systemic infection in the partner.
The nation faces a prolonged STD crisis.
In 2021, gonorrhea reached its highest level since 1991 and syphilis since 1990.
Meanwhile, chlamydia rates have nearly doubled since two decades ago.
STDs do not always have symptoms and, if left undiagnosed and untreated, can have serious health consequences.
Syphilis is among the most threatening, as it can be a direct cause of death (while human papillomavirus, HIV, and hepatitis more commonly cause death due to secondary conditions).
This year, syphilis rates reached their highest level since the 1950s. An annual report from the CDC showed that 207,300 cases of STDs, which can cause sores in the genitals and mouth, were diagnosed nationwide in 2022, the latest year available.
That marked a 17 percent increase in one year and an 83 percent increase compared to five years ago.
Without treatment, patients who develop sores are at risk of the disease spreading to the brain and spinal cord, which can lead to vision loss, sensory problems, psychosis, paralysis or stroke.
Experts have pointed to a number of reasons for rising STD rates, including a drop in condom use, fewer local sexual health clinics and rampant drug use.
Hepatitis E is usually spread through contact with feces, such as touching fecal particles and putting your hands in your mouth, drinking unclean water, and eating raw pork.
The risk of dying from hepatitis E infection is low, less than four percent.
However, the risk is considerably higher in pregnant women.
About 10 to 30 percent of pregnant women infected with HEV die in the third trimester. Pregnancy alters the immune system, making the mother’s body less able to fight infections.