MONROVIA, Liberia, May 2 (UPI) -- Men who have survived and have largely rid their bodies of the deadly Ebola virus, can still pass it on to other human beings through sexual activity for some time after they recover, the Center for Disease Control and Prevention said in a new report.
The potential for male survivors to transmit the virus was discovered by the CDC in the West African nation of Liberia, where a man infected a woman through unprotected sex. After ruling out all other infection causes, officials said the pair had sex 199 days after the man first experienced Ebola symptoms.
The finding was reported in the CDC's Morbidity and Mortality Weekly Report, released Friday.
It's the first time since the virus was discovered in 1976 that officials believe a woman has been infected with Ebola during sex with a male survivor.
The 44-year-old woman in Monrovia, Liberia, started showing Ebola symptoms on March 14 -- one week after she had intercourse with a male survivor, the report said. While health officials knew traces of the virus can remain in the human body after treatment, they were previously unaware it could remain so long in male seminal fluid.
The CDC had previously advised male survivors to abstain from sex completely or use a contraceptive for 90 days after recovery, since the virus had been found in semen up to 101 days after symptoms set in. But because it's believed the woman was infected 199 days after her male partner first showed signs of Ebola, officials now believe that advice may not be enough.
"We have suspected that having sexual contact with survivors could be a potential way for people to become infected," Ebola CDC expert Dr. Barbara Knust said. "Prior to this outbreak we did have messages given to male survivors to abstain from sex for three months and they were provided condoms."
Due to the new findings, the agency now advises people to refrain from sex with previously infected men indefinitely.
"I want to emphasize that we don't think this is lifelong," Dr. Knust said. "We think it's for some period of time for survivors. The thing that's difficult about this public health message is we don't know how many months that is. But it's not like HIV, where those recommendations are lifelong."
Sexual transmission of Ebola might only be possible by men, officials say, because no evidence suggests recovered females can pass it on to a sexual partner.
Part of the reason sexual infection of the virus still isn't fully understood is because in the past Ebola survivors were rare. Now, as experts monitor those who have beaten the virus they are discovering new ways the virus behaves in the body.
"There will be many things we'll learn from survivors about how people recover and how better to treat and protect people," Dr. Knust said.