U of M researchers head to West Africa to study how Ebola affects reproductive system
Scientists discover virus lives on for months in male reproductive organs
As the Democratic Republic of the Congo continues fighting the second largest Ebola virus outbreak in history, University of Manitoba researchers will travel to West Africa to help prevent survivors from sexually transmitting the disease.
Jason Kindrachuk, an associate professor from the U of M who is part of the team, said half of all male Ebola survivors who pass a blood test for the virus will unknowingly carry it in their reproductive systems for anywhere from four months to three years.
That means despite the practice of placing those with Ebola in quarantine during outbreaks, a patient who is cleared can transmit the disease through sexual intercourse, not knowing the virus is still present in his reproductive tract.
"What we know about the Ebola virus is that it decimates most major organs it infects," Kindrachuk said.
"But it doesn't seem to do that in the reproductive system in males. It stays and persists for a long period of time."
Kindrachuk and two PhD candidates from the U of M will travel to Sierra Leone to interview Ebola survivors about any long-term sexual health complexities they've experienced, such as changes in hormone levels and libido, and the ability to conceive.
The West African country is 4,000 kilometres away from the current outbreak but was part of a previous outbreak.
Before going to Africa, the team is starting to analyze how and why Ebola gets into the reproductive system and the effects it has on the system.
"Ultimately, what our work is going to be able to do is help guide outbreak containment strategies."
Little knowledge about Ebola
"We still really don't understand how this virus does what it does to humans," Kindrachuk said. "Nor do we truly know where it comes from in nature."
Ebola virus first appeared in Africa in 1976, the World Health Organization says. It is a rare but severe illness that destroys the human body from the inside.
On average, people who contract the virus have a 50/50 chance of surviving.
Researchers believe the virus is transmitted to people from wild animals, and carried mainly by bats. Researchers believe the animal can carry the virus without getting sick, Kindrachuk said.
Bats may be able to transmit the virus by biting a human, or biting an animal that is later consumed by somebody, he said. It's also common for people in Africa to eat bats, so if Ebola is alive in the animal during consumption, that is another way the disease can be transmitted.
"There is, realistically, any number of mechanisms how humans can get infected," Kindrachuk said.
"It's really difficult for us to figure out how to stop this virus in its tracks before it starts to spread."
Once contracted, the virus spreads through human-to-human contact with bodily fluids, such as blood or feces, of someone who has or died from Ebola. The illness also can spread if someone touches an object contaminated with the bodily fluids of someone infected with Ebola.
That's why it's not uncommon for health-care workers to get infected during an outbreak.
Now that researchers know survivors also can transmit the virus, there is much more to learn, Kindrachuk said.
Ebola and the reproductive system
Kindrachuk and his team are trying to find out how and why the virus gets into the reproductive system, and why it stays there for so long.
"These are big unanswered questions for us, if you ever want to be able to circumvent outbreaks within these regions of the world," he said.
Although the data is still being pieced together, there is evidence suggesting Ebola can impact long-term semen health, he said.
University of Manitoba PhD candidate Andrew Webb, another member of the team, is studying how tissues of the immune system protect those of the reproductive system. He's using tissue samples from mice, but Kindrachuk said the team is waiting for approval to gain access to human samples.
Webb told CBC News that, from what he has seen so far, is that the Ebola virus interacts with testicular cells differently than the rest of the body.
"The cells do get infected, but somehow they're managing to sort of limit the replication of the virus in the cells," he said.
"Basically, the cells are acting as a sort of reservoir where the virus persists, and it is alive and replicating, but at a much slower pace. That's allowing the cells to handle the virus instead of reacting heavily to it, and causing a chain reaction that leads to cell death.
"The testicular cells… are hosting the virus, limiting the growth, without necessarily killing it off."
Kindrachuk said the team will soon use mice to see how often they can transmit Ebola through intercourse, and how it gets into a male mouse's testicles.
Female reproductive system
There have been a few cases where a woman sexually transmitted Ebola to a man, but when it comes to how Ebola affects the female reproductive system, there are very few leads, Kindrachuk said.
He said the data's gender bias could be due to a general lack of testing on women, or because women are reluctant to be studied.
From what little data is available, Kindrachuk said the virus appears to linger in women less often than in men.
He hypothesizes that this is due to the vast differences between the male and female reproductive tracts, and it's possible "the female reproductive tract has a strong enough defence system to help reduce the amount of virus that the reproductive tissue receives."
What Kindrachuk called "the million-dollar question" that desperately needs to be answered is whether Ebola can be passed on genetically.
Kids infected by Ebola have a high fatality rate, so researchers believe they may be more susceptible to the virus, but there's no hard evidence supporting that theory.
Women with the virus who become pregnant often get abortions, Kindrachuk said, but the babies who have been born have shown no signs of being infected.
When to expect published findings
"In about two to five years, we'll be able to put together quite a few stories, and have a pretty good blueprint in terms of what is going on with Ebola virus persistence," Kindrachuk said.
The research currently underway will allow findings to be published sooner once touching down in Sierra Leone, but the process of studying samples and survivors will slow down once the team's in Africa, he said.
"There are some obstacles in terms of equipment, and a little bit in terms of facilities," Kindrachuk said.
Webb, the PhD candidate, said the stigma associated with Ebola also could slow the research in Sierra Leone.
"There are a lot of ethical issues surrounding taking samples," Webb said. "We're going to have enough trouble as it is getting Ebola virus survivors to provide survey feedback.
"It will depend on whether or not we can convince them of our positive benefits, of whether or not we'll allow them to have a better life."
Until answers are found, survivors are being told to use condoms during sex or to be abstinent, Kindrachuk said.
The outbreak in Congo started just over a year ago; there have been 3,228 total cases and 2,153 people have died, the latest data from the World Health Organization says.
Last week, the WHO said the number of new cases is declining. Its latest risk assessment said there are 15 new cases per week, which is significantly down from 128 per week at the outbreak's peak.
Kindrachuk was a health-care worker in Sierra Leone while West Africa suffered the largest Ebola outbreak in history.
The outbreak spanned from 2014 to 2016, and according to data from the WHO, there were over 25,000 total cases, and more than 11,000 people died.