Health officials are optimistic that the West African outbreak of Ebola that has killed almost 11,000 people is winding down. They are worried about an outbreak of the deadly virus as a sexually transmitted disease after a woman caught the virus during sex with a survivor who had Ebola more than six months ago.
A 44-year-old woman from Monrovia, Liberia, was diagnosed with Ebola in late March, approximately two weeks after having unprotected sex with a 46-year-old male survivor, who was hospitalized with the virus last September. Doctors have advised people that it is possible to pass on Ebola via semen for some time, but they believed that 90 days after recovery was an adequate wait period. (The previous observed limit for the virus surviving in semen was 82 days.) But, the tests confirm the situation, and officials have rules out all other possible sources of infection for the woman, which means that the virus survived in the man’s semen for almost 200 days.
This is the first time public health officials know of that the Ebola virus was transmitted during sex. They knew is could remain in the body fluids, including semen, for a while, but the case in Liberia surprised them. Part of the reason sexual transmission of the virus still is not fully understood is previous outbreaks had fatality rates up to 90 percent. They have learned a lot from the rare survivors, since the deadly disease first flared up in 1976, but this outbreak is yielding more information, and success in treating the virus, than before.
“We have suspected that having sexual contact with survivors could be a potential way for people to become infected,” explained Dr. Barbara Knust, an Ebola expert at the U.S. Centers for Disease Control and Prevention (CDC). While the advice to the rare male survivors has been to use condoms for three months, the CDC and other health organizations are now recommending that people refrain from having unprotected sex with previously infected men indefinitely.
Knust did say that, unlike HIV where recommendations to use condoms are lifelong, they do not believe the need for protected sex is ongoing. The issue is that they do not know enough about the potential infection period from semen.
Officials do believe that Ebola may only be transmitted during sex with male survivors. There is no evidence that female survivors can pass the disease along during sex.
While the woman’s infection is alarming, the good news is that no new Ebola cases were identified in Liberia for approximately five weeks. Health experts declare countries to be Ebola-free if no new cases are diagnosed for 42 days after the last infection (two times the normal 21-day incubation period). It is not clear if this sexually transmitted case will change that practice. The World Health Organization reported that 33 new cases were diagnosed in Guinea and Sierra Leone; that is a much lower rate than in the past showed progress in stopping the epidemic, which has infected more than 26,000.
The good news, if there is some silver lining to this fourteen-month-long battle against Ebola, is that there are more than 15,000 survivors public health officials can monitor. The vaccines and treatments being tested, for example, were derived from antibodies taken from blood of survivors. In addition, knowledge about Ebola being transmitted during sex, as well as any long-term physical impacts, will also grow with a large survivor population to follow.
By Dyanne Weiss