A 27-year-old South Australian man is in a serious condition in hospital with suspected Murray Valley Encephalitis a disease not seen in humans in South Australia since 1974.
Chief medical officer Paddy Phillips says another 47-year-old man's also in hospital with a confirmed case of MVE but he's in a stable condition.
Professor Phillips says MVE is a serious illness with no specific treatment or vaccine.
The virus is spread through mosquito bites and was recently detected in birds in South Australia's lower Murray region.
Professor Phillips says health authorities are working with local councils on mosquito control programs but the best protection against MVE is to avoid bites.

