Sample A: Cover Page of Thesis, Project, or Dissertation Proposal

2.1.3 GEOGRAPHIC DISTRIBUTION
Since the first major outbreak of RVF was recorded close to Lake Naivasha in Kenya
in 1930-1931 (Daubney et al. 1931, CDC 2004b), RVF outbreaks in Africa have occurred as
far north as Egypt, throughout most of sub-Saharan Africa and as far south as Southern
Africa (House et al. 1992, Davies and Martin 2003). One of the most notable epizootics of
RVF occurred in Kenya in 1950-1951 and resulted in the death of an estimated 100,000
sheep (CDC 2004b). The 1977 RVF outbreak in Egypt resulted in both animal and human
cases and is believed to have started due to the importation of RVF virus infected domestic
animals from Sudan (Gad et al. 1986, Peters and Linthicum 1994). In 1987 transmission of
the RVF virus to humans in West Africa (Senegal, Mauritania) was linked to the altered
interactions between humans and mosquitoes that resulted from flooding of the lower
Senegal River during construction of the Senegal River dam project (CDC 2004b). In 1997-
1998 a RVF outbreak in East Africa affected 89,000 people and caused over 400 deaths
(Gerdes 2004). A severe form of the disease was seen in Mauritania (1998) where many
thousands of people became sick, 200 people died, and abortion losses in livestock were
heavy (CDC 2004b, Gerdes 2004). The 2000 outbreak in Saudia Arabia and Yemen was
particularly alarming as this was the first time RVF virus was detected outside the African
continent (Ahmad 2000, Jupp et al. 2002, Anyamba et al. 2006), and it demonstrated the
potential for the virus to spread with devastating consequences to previously uninfected areas
with a variety of different ecological conditions (e.g., wet and tropical areas such as the
Gambia, hot and arid areas such as Yemen, irrigated regions such as the Senegal River
valley) (Chevalier et al. 2004a). As in other Rift Valley fever outbreaks, the November 2006
outbreak in the horn of Africa began after several months of heavy rains that caused floods
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