East Africa had a regional outbreak of Rift Valley fever in late 2006 that affected Kenya, Somalia, and Tanzania. During outbreak, 1062 people were infected with Rift Valley fever and 394 people died between December 2006 and December 2007. Rift Valley fever (RVF) is caused by a phlebovirus in the Bunyavirales order which is transmitted by mosquito bite and contact with infected animal blood; it mainly infects livestock that come into infectious contact with a viral reservoir but human beings can also be infected. The outbreak began after a heavy El Niño rain season across East Africa left greater than usual breeding ground for Aedes aegypti mosquitos, with particularly heavy rainfall over eastern Kenya, central Tanzania, and southern Somalia. While most people infected with the virus experience a relatively mild, flu-like illness without hospitalization, around 8% will develop a severe illness that can include eye disease, encephalitis, hemorrhagic fever and death. During this outbreak, of the 1,062 hospitalized, laboratory-confirmed RVF cases (via anti-RVF ImG) assays, 37% died. Epidemic Kenya Unusually heavy rains in Kenya's eastern and coastal regions caused widespread flooding in October 2006 and provided extensive breeding grounds for mosquitos capable of transmitting Rift Valley fever. On 30 November 2006 a man identified as the RVF index case began to show symptoms in Kenya's Garissa County, and he checked into a hospital the next day. By mid-December, the Ministry of Health had received reports of deaths from an illness featuring fever and generalized bleeding. Mild cases had likely gone undetected for weeks before the region's mosquito populations climbed after one of the area's heaviest recorded rain seasons. 11 deaths from RVF were reported in Garissa by December 20. Cases of began to cluster in Garissa and Baringo counties areas that had been having high livestock mortality and morbidity rates, which attracted the Kenya Ministry of Health's attention. The WHO alerted the Global Outbreak and Response Network (GOARN) on December 22 and, in response to a January 2 request for help, sent an 11-member team from GOARNS partners to assist the Ministry of Health in addition regional, provincial governments. The outbreak peaked on December 27, when Garissa's authorities issued a ban on slaughtering livestock. Other county's began to follow suit with their own bans on the slaughtering of animals, wary of transmission from slaughtered animals. The Baringo district experienced a total of 169 cases of RVF. A ban on the