Children play games on an open ground in Kibera slum, Nairobi, Kenya, on Oct. 16, 2015. The Kibera slum is the biggest slum in Africa and one of the biggest in the world. The Ministry of Devolution of Kenya and UN-Habitat are trying to help and improve this situation, but it is painfully slow. Photo: Xinhua 

Photo taken on Oct. 16, 2015 shows a view of Kibera slum of Nairobi, Kenya. The Kibera slum is the biggest slum in Africa and one of the biggest in the world. The Ministry of Devolution of Kenya and UN-Habitat are trying to help and improve this situation, but it is painfully slow. Photo: Xinhua 

A man walks along a railway in Kibera slum, Nairobi, Kenya, on Oct. 16, 2015. The Kibera slum is the biggest slum in Africa and one of the biggest in the world. The Ministry of Devolution of Kenya and UN-Habitat are trying to help and improve this situation, but it is painfully slow. Photo: Xinhua 

Photo taken on Oct. 16, 2015 shows a view of Kibera slum of Nairobi, Kenya. The Kibera slum is the biggest slum in Africa and one of the biggest in the world. The Ministry of Devolution of Kenya and UN-Habitat are trying to help and improve this situation, but it is painfully slow. Photo: Xinhua