U.S. officials warn of new mosquito disease Associated Press Atlanta — As if West Nile virus were not bad enough, U.S. health officials are now on the lookout for another mosquito-borne disease, fearing it could become a permanent part of the U.S. landscape if it entered the country. Rift Valley fever, which originated in Africa, is the only disease at the top of both human health and agriculture lists of dangerous diseases. The virus can kill people, with a near 1-per-cent mortality rate, making it deadlier than West Nile. Rift Valley also poses a greater threat to cattle and sheep....
