1 WHO Health Emergencies Programme, World Health Organization, 1211 Geneva, Switzerland.
2 Department of Food Safety and Zoonoses, World Health Organization, 1211 Geneva, Switzerland. Electronic address: benembarekp@who.int.
3 WHO Health Emergencies Programme, World Health Organization, 1211 Geneva, Switzerland; WHO Regional Office for Africa, Brazzaville, PO BOX 06, Brazzaville, Republic of Congo.