GENEVA - The Philippines has banned imports of pigs and pig products from Laos due to an African swine fever outbreak, it said in filings published by the World Trade Organization on Tuesday.

The Philippines' move follows similar steps by China and Thailand, following an outbreak in Laos' southern province of Saravane.

The Philippines also said it was introducing new "biosecurity measures", such as a quarantine period, for imports of plant-based feed products from countries with the disease, citing scientific evidence that African swine fever can spread via feed products.

The extra controls on feed imports apply to Belgium, Bulgaria, Cambodia, China, Hong Kong, Hungary, Laos, Latvia, Moldova, Poland, Romania, Russia, Ukraine and Vietnam.

The disease, which is incurable in pigs but harmless to humans, has spread rapidly across China since last August and also spread this year in Vietnam. China has reported 137 outbreaks so far, but more are going unreported.

As many as half of China's breeding pigs have either died from African swine fever or been slaughtered because of it, twice as many as officially acknowledged, according to the estimates of four people who supply large farms.

(Reporting by Tom Miles; Editing by Andrew Cawthorne)