MANILA • The Philippines wants operators who raise pigs in their backyards - accounting for 65 per cent of the nation's hog output - to be more vigilant in monitoring for African swine fever after dozens of the animals were found dead in the Manila area.

The carcasses of about 40 pigs were in a river in Marikina City and six were in a creek in Quezon City, according to a report by ABS-CBN News. It will take two weeks before the government gets confirmation on whether the highly contagious viral disease caused the deaths.

"It was utterly irresponsible on the part of the backyard raisers, as they did not only violate current laws, but their misdeed also spread the disease pathogens much faster," Agriculture Secretary William Dar said in a statement yesterday.

The Philippines' 260 billion peso (S$6.9 billion) swine industry provides livelihood to millions, as it is dominated by small operators who raise pigs in their backyards. The virus is not known to harm humans.

Reports of recent deaths came even as Agriculture Department spokesman Noel Reyes said last Friday that the authorities were "110 per cent sure" that swine fever was contained in affected areas in Rizal and Bulacan, where pig deaths were first discovered weeks ago.

Those found dumping the carcasses will be punished for violations against animal welfare and solid waste management, said Mr Dar.

BLOOMBERG