%0 Journal Article
%T Bovine epizootic encephalomyelitis caused by Akabane virus in southern Japan
%A Ryota Kono
%A Miki Hirata
%A Masaya Kaji
%A Yukitoshi Goto
%A Shogo Ikeda
%A Tohru Yanase
%A Tomoko Kato
%A Shogo Tanaka
%A Toshiyuki Tsutsui
%A Tadao Imada
%A Makoto Yamakawa
%J BMC Veterinary Research
%D 2008
%I BioMed Central
%R 10.1186/1746-6148-4-20
%X Nonsuppurative encephalomyelitis was observed in cattle that showed neurological symptoms such as astasia, ataxia, opisthotonus and hypersensitivity in beef and dairy farms by histopathological analysis. Akabane viral antigen and genome were consistently detected from the central nervous system of these animals, and the virus was isolated not only from them but also from the blood samples of clinically healthy calves in the epidemic area. The isolates were classified into genogroup I a containing the Iriki strain, which caused encephalitis of calves almost twenty years ago in Japan. Most of the affected cattle possessed the neutralizing antibody against Akabane virus. Seroconversion of the cohabitated and sentinel cattle in the epidemic area was also confirmed during an outbreak of the disease.The ecological and epidemiological data we have obtained so far demonstrated that the Akabane virus is not endemic in Japan. No evidence of Akabane virus circulation was observed in 2005 through nation-wide serological surveillance, suggesting that a new strain belonging to genogroup I a invaded southern Japan from overseas in the summer of 2006 and caused an unprecedented epizootic of encephalomyelitis mainly in susceptible calves. It will be necessary to reconsider the vaccine strategy to control the disease effectually.Akabane virus is classified into the genus Orthobunyavirus in the family Bunyaviridae. It is widely distributed from the tropical to temperate zones of the world and has been associated with hematophagous arthropod vectors such as Culicoides biting midges and mosquitoes, and with ruminants [1-4]. Akabane virus causes epizootic and sporadic outbreaks of abortions, stillbirths, premature births and congenital malformations characterized by arthrogryposis-hydranencephaly syndrome when susceptible pregnant cattle, sheep and goats are infected [5-7]. These outbreaks have been observed in Japan, Korea, Taiwan, Australia, Israel and Turkey [1,8,9], and have repeated
%U http://www.biomedcentral.com/1746-6148/4/20