Ebola survivors can still transmit the disease

Ebola patient treated in isolation. License: PD

Ebola is a nasty, nasty disease, incurable, extremely virulent, and with a high mortality rate. Its last devastating outbreak in West Africa in the past couple of years compelled the governments and pharmaceutical agencies to invest heavily in the search of a cure or a vaccine. As a result, there are already a dozen or so of possible vaccines being tested in various phases of drug development. Some hold real promise and, hopefully, one would breed true very soon.

But that’s not what today article is about. It is about the Ebola survivors. If the patient is still alive after two weeks from symptoms onset, there are very good chances s/he will survive it. Depending on the country, the survival rates vary between 10% up to 75%, with the average being about 50% (that is, you got one chance in two to survive Ebola).

It is very difficult to conduct thorough testing on Ebola survivors, mainly due to poor accessibility to them. However, Thorson et al. (2016) looked at all the available evidence, from published articles to non-peer-reviewed papers, from WHO data (World Health Organization) to personal communications and Internet feeds to see if Ebola survivors can still transmit the disease.

In short: yes, they can, unfortunately. Primarily through sexual transmission, as the authors found reports of Ebola being present in the sperm up to 284 days after symptom onset (and possibly even longer). Also, there are reports of sexual partners being infected by an Ebola survivor.

The authors (and the WHO) recommend that the survivors should be tested every 3 months and declared free of Ebola only when RT-PCR (reverse transcription polymerase chain reaction, a method that detects RNA expression) is negative twice. Meanwhile, Ebola survivors should practice abstinence. Or, use condoms, although the virus is really small (80 nm), therefore a condoms may not present an impenetrable barrier.

Reference: Thorson A, Formenty P, Lofthouse C, & Broutet N (Jan 2016). Systematic review of the literature on viral persistence and sexual transmission from recovered Ebola survivors: evidence and recommendations. BMJ Open, 6:e008859. doi:10.1136/bmjopen-2015-008859.  Article | FREE PDF

By Neuronicus, 10 January 2016