Centers for Disease Control and Prevention Director Robert Redfield said Monday that the Ebola outbreak in conflict-ridden Congo has become so serious that international public health experts need to consider the possibility that it cannot be brought under control and instead will become entrenched.

If that happened, it would be the first time since the deadly viral disease was first identified in 1976 that an Ebola outbreak led to the persistent presence of the disease. In all previous outbreaks, most of which took place in remote areas, the disease was contained before it spread widely. The current outbreak is entering its fourth month, with nearly 300 cases, including 186 deaths.

If Ebola becomes endemic in substantial areas of North Kivu province, in northeastern Congo, “this will mean that we’ve lost the ability to trace contacts, stop transmission chains and contain the outbreak,” said Tom Inglesby, director of the Johns Hopkins Center for Health Security, which hosted the briefing on Capitol Hill that featured the Ebola discussion with Redfield.

Read more in the Washington Post.