GENEVA (AP) — The head of the World Health Organization said on Wednesday the risk of global spread of the Ebola outbreak in Congo and Uganda is high at national, regional levels but low at the global level.

WHO Director-General Tedros Adhanom Ghebreyesus said so far 51 cases have been confirmed in Congo in the northern provinces of Ituri and North Kivu provinces in Congo, “although we know the scale of the epidemic is much larger.”

He said Uganda has also told the U.N. health agency of two confirmed cases in Uganda’s capital, Kampala. “Beyond the confirmed cases, there are almost 600 suspected cases and 139 suspected,” he said. “We expect those numbers to keep increasing.”