The epidemic of Rift Valley Fever in Sudan continues, with more than 250 human cases of hemorrhagic fever caused by the virus so far identified, and at least 84 deaths. Although the Sudanese Ministry of Health has now publicly confirmed the epidemic as Rift Valley Fever, they have denied that the spread of the virus is due to infection of sheep, cows and other domestic animals. Although infection with Rift Valley Fever virus can often cause clinical signs in animals (infected sheep, for example, have above average rates of abortions and deaths of lambs). However, infection is asymptomatic in many other animals. Given the growing spread of the epidemic, the Ministry has taken samples from animals found in the regions where the epidemic has spread, and are expecting results this week. The WHO and the World Organization for Animal Health suspect that infections of domestic livestock may be having a large impact on the human epidemic. If animal infections are prevalent, it will have enormous economic repercussions, given the importance of cattle farming to the national economy.