HANOI, March 27 (Xinhua) -- African swine fever (ASF) has stricken Vietnam's northern Vinh Phuc province, bringing the total number of the disease-hit localities to 23, local media on Wednesday quoted the country's agriculture ministry as reporting.

ASF outbreaks have so far been detected in 476 communes, 91 districts, 23 cities and provinces in the northern and central regions, leading to the culling of some 73,000 pigs, online newspaper Sai Gon Giai Phong (Saigon Liberation) quoted the Ministry of Agriculture and Rural Development as reporting.

ASF has affected over 20 countries and regions so far, and there is no approved vaccine against the disease, 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 human, but causes hemorrhagic fever in pigs and wild boars which is almost fatal.