Skip to content

Researchers Puzzled by Latest Ebola Outbreak

Researchers say that an Ebola outbreak now occurring in Guinea was almost certainly started by someone who survived West Africa’s historic 2014-16 epidemic, harbored the virus for at least five years and then transmitted it via semen to an intimate partner. The finding, based on genetic sequencing of virus samples taken from patients in the current outbreak, shocked researchers. Until now, the longest the virus had been known to persist in a survivor was 500 days. “It’s a stunner,” Dr. William Schaffner, an infectious-disease expert at Vanderbilt University who was not involved in the research, said in an interview. “This is an extraordinary phenomenon.” The current outbreak in Guinea was first recognized in January and has infected at least 18 people and killed nine. The new finding also raises the possibility that other outbreaks in the region, assumed to have begun with transmission from animals, may actually have been started by survivors with unrecognized, lingering infections. One possible solution, Dr. Schaffner said, would be “to vaccinate much of equatorial Africa” against Ebola even where there is no current outbreak. Effective vaccines are available, one made by Merck and another by Johnson & Johnson, but so far they have generally been used only in response to outbreaks.