Ali Ahmed Yahaya, a program manager with the World Health Organization (WHO) Regional Office for Africa, speaks during an interview with Xinhua in Brazzaville, capital of the Republic of Congo, Aug. 7, 2019. WHO will continue its efforts to help fight Ebola in the country, Ali Ahmed Yahaya told Xinhua. (Xinhua/Wang Teng)

Photo taken on Aug. 7, 2019 shows the World Health Organization (WHO) Regional Office for Africa in Brazzaville, capital of the Republic of Congo. WHO will continue its efforts to help fight Ebola in the country, Ali Ahmed Yahaya told Xinhua. (Xinhua/Wang Teng)

Ali Ahmed Yahaya, a program manager with the World Health Organization (WHO) Regional Office for Africa, speaks during an interview with Xinhua in Brazzaville, capital of the Republic of Congo, Aug. 7, 2019. WHO will continue its efforts to help fight Ebola in the country, Ali Ahmed Yahaya told Xinhua. (Xinhua/Wang Teng)