Key messages
Sexual transmission of the Ebola virus may be possible, but has not yet been verified or documented.
No formal evidence exists of sexual transmission, and current knowledge is based on studies that were designed to answer other aims. Sexual transmission from convalescent patients cannot be ruled out. Men who have recovered from Ebola virus disease (EVD) should be aware that seminal fluid may be infectious for at least three months after onset of EVD symptoms.
Evidence of persisting Ebola virus RNA in vaginal secretions of convalescent women is weaker than what is known for persistence in semen. No reports of positive viral isolation in vaginal fluids exist.
Ebola virus may persist in other bodily fluids as well, such as breast milk, urine and sweat, but evidence is still very weak.
Because of the potential/unknown risk of sexual transmission of the virus, men and women who have recovered from EVD should abstain from all types of sex (including oral sex) for three months after onset of symptoms.
It is likewise important for convalescent Ebola patients to maintain good hand and personal hygiene after masturbation, by washing with soap and water.
If sexual abstinence is not possible, male or female condoms offer some protection and condom use is hence recommended. Used condoms should be handled with caution, and contact with seminal fluids avoided. After handling of condoms hands should be washed with soap and water.
WHO does not recommend isolation of male or female convalescent patients whose blood has been tested negative for Ebola virus.
1. Live virus and RT-PCR positive
Different tests for identifying Ebola virus in semen and other bodily fluids exist. Virus isolation identifies viable, and potentially infectious, virus. More rapid methods for detection such as RT-PCR will show the presence of fragmented viral particles. To what extent virus detected with RT-PCR represent live, infectious virus may vary by case and also laboratory.
2. How long is live Ebola virus present in semen and other bodily fluids?
There is evidence that seminal fluids of convalescent men can shed the Ebola virus for at least 82 days after onset of symptoms. There is limited evidence suggesting that live Ebola virus can persist in urine for 26 days following symptom onset.
The evidence of detected Ebola virus in vaginal secretions is weak: traces of Ebola virus was detected in vaginal secretions of a woman on the 33rd day after her symptom onset. Whether these traces found in vaginal secretions represent live virus, and if so how long it would remain in vaginal secretions, is not known. Likewise traces of Ebola virus was detected in the sweat of one recovering patient, on the 40th day after his symptom onset, while no live virus could be isolated in cultures from his sweat.
3. Is semen or other bodily fluids that test positive for Ebola virus in convalescent patient, infectious?
No evidence exists of transmission from a convalescent patient via an outside-host route, but few studies have targeted this potential transmission pathway.
So far no formal evidence has been presented that shows a verified sexual transmission of Ebola virus between a recovered patient and his or her sexual partner, but sexual transmission from convalescent patients cannot be ruled out.
Until more knowledge exists sexual abstinence is recommended for three months, as outlined in the key-messages. Isolation of male or female patients is however NOT recommended.