Rio de Janeiro has dengue fever epidemic

Officials in Rio de Janeiro say there have been more than 50,000 cases of dengue fever in the Brazilian city recently, including 500 in the last week. \"We have a plan focused on the epidemic and we will continue with the state of alert,\" Hans Domain, the city\'s health secretary, told Merco Press. \"This is the moment when we most need the collaboration from citizens, because our priority now is prevention of the disease.\" Domain said last week 517 cases were reported, but the number of cases per 100,000 inhabitants was already above 300, \"which is really alarming.\" Twelve deaths were reported. Dengue fever is a tropical disease caused by the dengue virus, which is transmitted via mosquitoes. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles. In a small proportion of cases, the disease develops into the life-threatening dengue hemorrhagic fever. There is no approved vaccine, so prevention depends on reducing the habitat for mosquitoes -- standing water.