Rift Valley Fever, a highly contagious virus, has killed 74 people in Kenya and infected hundreds more after spreading from the north-eastern region to the coast. The Kenyan Ministry of Health this week said the over two hundred more are infected. The fever, which is spread through mosquito bites or movement of contaminated animals, causes flu-like symptoms and can lead to death through bleeding. The highly infectious nature of the disease also makes it difficult for health officials to treat. The government says the disease -- which was earlier confined to the north-eastern province where nomadic herders criss-cross the arid land with their livestock in search of water and pasture -- had now crossed over to the neighbouring coast province. In the capital Nairobi, butchers like Albert Mwenes who roasts beef at his establishment, complained of poor sales. "Since this disease started sales have declined. The majority of people are not eating meat, they end up consuming alternatives like chicken and fish. Others go for boiled meat instead so the roast beef business is really low," he explained. Many city residents say they have stopped eating meat inorder to avoid contracting the disease. Health officials have however advised residents to ensure they boil their beef before consumption. "Now this disease has spread to many areas and it is continuing to kill people. We are even being told not to drink milk now, everyone is wondering what we are going to do," said Rhoda Mwai, a Nairobi resident. Most human cases of Rift Valley Fever are relatively mild, but it can develop into a much more severe disease, according to the U.N. health agency which says the overall case fatality rate is typically less than one percent. But most of the region's people are livestock farmers, so an outbreak has health as well as economic implications. An outbreak of Rift Valley Fever was blamed for the deaths of hundreds of people in Kenya in 1997-1998.