HANOI, April 22 (Xinhua) -- Porcine Reproductive and Respiratory Syndrome (PRRS), known as "blue ear" disease, has recently stricken two more Vietnamese provinces, raising the total number of affected localities to 10, local newspaper Pioneer reported Tuesday.

    Specimens from ill pigs in Yen Mo of northern province of Ninh Binh and Y Yen of Nam Dinh province were tested positive to PRRS virus, the paper quoted the country's Department of Animal Health as reporting.

    Now, PRRS is hitting the provinces of Thanh Hoa, Thai Binh, Thai Nguyen, Nam Dinh and Ninh Binh in the northern region, and HaTinh, Quang Nam, Nghe An, Lam Dong and Thua Thien Hue in the central region, said the department.

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