A picture taken on January 12, 2020 shows a World Health Organization (WHO) sign at its headquarters prior to a combined news conference following a two-day international conference on COVID-19 coronavirus vaccine research and a meeting to decide whether Ebola in DR Congo still constitutes health emergency of international concern in Geneva. (Photo: AFP)

An Ebola vaccination campaign has begun in the city of Butembo, in eastern Democratic Republic of Congo, the World Health Organization (WHO) said in a tweet.

Health workers at Matanda health center were the first to be vaccinated on Monday, the WHO said.