HANOI, March 9 (Xinhua) -- Quang Ninh and Ninh Binh in Vietnam's northern region have become the latest two Vietnamese localities stricken by African swine fever (ASF), Vietnam News Agency reported on Saturday.

Earlier on Friday, the Vietnamese Department of Animal Health announced ASF affected 333 farming families and small pig farms in 10 localities, namely capital Hanoi, Hai Phong city, Hung Yen, Hai Duong, Thai Binh, Ha Nam, Thanh Hoa, Hoa Binh, Dien Bien and Thai Nguyen provinces.

To date, ASF outbreaks have been detected in 12 Vietnamese localities, killing and leading to the forced culling of 11,500 pigs, Vietnam Central Television reported on Saturday.

ASF have affected 21 countries so far, and there is no approved vaccine against the disease now, according to the World Organization for Animal Health.

ASF is a severe viral disease affecting domestic and wild pigs which can be spread by live or dead pig and pork products, the organization said, noting that the ASF virus is harmless to humans, but causes hemorrhagic fever in pigs and wild boars that is almost fatal.