HANOI, April 16 (Xinhua) -- Porcine Reproductive and Respiratory Syndrome (PRRS), known as "blue ear" disease, has recently hit Vietnam's central Thua Thien Hue province, bringing the total number of affected localities to six, according to local newspaper Labor on Wednesday.

    By April 15, PRRS had stricken 434 communes and wards of 31 districts and towns of the six provinces of Thanh Hoa, Ha Tinh, Nghe An, Quang Nam, Lam Dong and Thua Thien Hue in the central and central highlands regions, leading to the death and the forced culling of over 149,000 pigs, the newspaper quoted the country's Department of Animal Health as reporting.

    Thanh Hoa alone has 337 communes and wards hit by the disease with a total of over 134,000 affected pigs.

    PRRS was first recognized in the United States in the mid-1980s and is now present in most pig producing countries. The symptoms include reproductive failure, pneumonia and increased susceptibility to secondary bacterial infection.