DAKAR, Senegal — Beds in Ebola treatment centers are filling up faster than they can be provided, evidence that an outbreak in West Africa is far more severe than the numbers show, an official with the World Health Organization said Friday.

The outbreak sweeping Guinea, Liberia, Sierra Leone and Nigeria is already the largest and deadliest ever. But the World Health Organization said Thursday that official counts of the dead and infected may still “vastly underestimate the magnitude of the outbreak.”

The flood of patients into every newly opened treatment center is evidence that the numbers aren't keeping up, Gregory Hartl, a spokesman for the U.N. health agency, said from Geneva.

Hartl said that an 80-bed treatment center opened in Liberia's capital in recent days filled up immediately.

The next day, dozens more people showed up to be treated.

KAMENSK-SHAKHTINSKY, Russia — Russia let Ukrainian officials inspect an aid convoy today and agreed to let the Red Cross distribute the aid around the rebel-held city of Luhansk, easing tensions and dispelling Ukrainian fears that the aid operation is a ruse to get military help to separatist rebels.In violation of an earlier tentative agreement, Russia had sent the convoy of roughly 200 trucks to a border crossing under the control of pro-Russia separatists, raising the prospect that it could enter Ukraine without being inspected by Ukraine and the Red Cross. Ukraine vowed to use all means necessary to block the convoy in such a scenario, leading to fears of escalation in the conflict.