(See also Overview of infections by Arbovirus, Arena virus and filovirus.) Chikungunya disease This disease is an acute febrile illness, followed by a more chronic polyarthritis. It is transmitted by Aedes mosquitoes and is in Africa, India, Guam, Southeast Asia, New Guinea, China, Mexico, Central America; Islands in the Caribbean, the Indian Ocean and the Pacific and limited areas of Europe spread. Local transmission was identified in Florida, Puerto Rico and the US Virgin Islands. For prevention of Chikungunya disease includes preventing mosquito bites Mayaro’s disease similar to dengue disease is transmitted by mosquitoes. It is widespread in Brazil, Bolivia and Trinidad. For prevention it Mayaro fever includes preventing mosquito bites tick-borne encephalitis in North Asia, Russia and Europe this infection is caused by three subtypes of flaviviruses: a Far Eastern subtype, a Siberian subtype and a European subtype. In the US, TBE is caused by Powassan virus, a flavivirus. First, a mild flu-like illness occurs, accompanied by leukopenia and thrombocytopenia, which disappears within a few days. About 30% of patients develop serious symptoms (eg. As meningitis, encephalitis). A vaccine is available in Europe and Russia California encephalitis The California encephalitis virus belongs to the family Bunyaviridae. This encephalitis and related infections are transmitted by mosquitoes and occur worldwide in the US Midwest and probable. The California encephalitis caused (eg., Fever, drowsiness, consciousness clouding, focal neurologic findings, seizures), especially in children symptoms. A Temporallappenbeteiligung can mimic a Herpes encephalitis; 20% of patients develop behavioral problems or recurrent seizures. The mortality rate is probably in <1%. There is no causal treatment available. Omsk hemorrhagic fever and Kyasanur forest disease These infections are transmitted by ticks or by direct contact with an infected animal (eg. As rodents, monkeys). Omsk hemorrhagic fever is caused by a flavivirus; it occurs in Russia, including Siberia, on. The Kyasanur forest disease, also caused by a flavivirus occurs in India. Omsk hemorrhagic fever and Kyasanur Forest Disease are acute febrile diseases which are accompanied by bleeding, low blood pressure, leucopenia and thrombocytopenia. Some patients develop encephalitis in the 3rd week. The mortality rate is <3% for Omsk hemorrhagic-fever and 3-5% in the Kyasanur forest disease. For prevention is to avoid tick bites and contact with infected animals. Rift Valley fever This infection is caused by a Phlebovirus is spread by mosquitoes and can be transmitted by the following:. Direct or indirect contact with the blood or organs of infected animals (eg in the slaughtering, cutting, or veterinary procedures) inhalation of infected aerosols intake of raw milk from infected animals Rift Valley fever occurs in South Africa, East and West Africa, the Arabian peninsula and Egypt. Rarely leads Rift Valley fever to eye diseases, meningoencephalitis or hemorrhagic form (which has a mortality rate of 50%). A vaccine for animals is available, and a human vaccine is under investigation.