By Tsegaye Tadesse ADDIS ABABA, Feb 20 (Reuters) - Ethiopia on Tuesday said there was no evidence its livestock had been infected by Rift Valley Fever, which has killed nearly 140 people in neighbouring Kenya. Fears that the deadly livestock-transmitted disease had headed north up the Great Rift Valley that passes through both eastern African nations have prompted Ethiopia's major livestock buyer, the United Arab Emirates, to ban Ethiopian meat imports. "Despite the ban imposed by UAE, which has affected our livestock market, no threat of Rift Valley Fever has been detected anywhere within the country," said Amsalu Demisse, acting head of the Agriculture Ministry's veterinary department. The dry season is also helping reduce the threat of transmission via mosquitoes since the insects have fewer areas of standing water in which to breed, Amsalu said. The other method of transmission is via close contact with infected animals, which have also been detected in parts of Somalia. "Ethiopia has also imposed restrictions on livestock movements along its border with Somalia and Kenya and a task force with the authority to prevent such movements has already been placed along its border," Amsalu said. Tanzania, which does not border Ethiopia, has reported two human deaths attributed to the disease. Untreated, Rift Valley Fever can cause severe bleeding, prompting victims to vomit blood and even bleed to death. Weight loss and blindness are other symptoms, Kenyan health officials say. An Ethiopian delegation last month went to the UAE to push for a lifting of the ban, Amsalu said. The Ethiopian Export Promotion Agency said UAE is one of Ethiopia's top meat markets, and that exports to the UAE had reached 2,497 tonnes in between June-December 2006 -- up 258 percent over the previous full year's 696 tonnes. Earnings rose 294 percent to $6.7 million in the six-month period compared to $1.7 million for the previous whole year. Ethiopia is home to sub-Saharan Africa's largest population of cows, with an estimated 40 million head of cattle. But the country's earnings from the sector are comparatively small because modern animal husbandry practices are not widespread, Amsalu said.