Almost half of tested pig-product seizures from Australian airports over a two-week period tested positive to African Swine Fever fragments, authorities say.

Fragments of the potentially devastating African Swine Fever virus have been discovered in almost half of sampled pig-product seizures at Australian airports.

Australian Chief Veterinary Officer Mark Schipp says the two-week probe - which took place in September at Sydney, Perth, Brisbane and Melbourne Tullamarine and Avalon airports - sampled 418 pig-product seizures from international travellers.

Of that number, 202 seizures were found to contain DNA fragments of the African Swine Fever virus, or 48 per cent, Dr Schipp told a foreign correspondents' forum in Sydney on Thursday.

A similar sample of seizures 12 months earlier turned up just six products with African Swine Fever fragments.

"At the border, we've increased screening on passengers," Dr Schipp said.

"We've increased the use of detector dogs and X-ray screens."

African Swine Fever is an untreatable, infectious virus that affects domestic pigs, warthogs and bush pigs and kills within days.

Humans cannot be infected but authorities predict the disease will eradicate up to a quarter of the global pig stocks and obliterate Asian piggeries.

The Department of Agriculture has banned all pork product imports from international travellers, and banned live pig importation.

Airlines have also been asked to stop serving pork meals on flights.

Dr Schipp said the disease had existed in Africa for centuries but had in recent years jumped across to European piggeries and on to Asia.

He said this was partly due to global trade but also recent trade conflicts, with some overseas importers required to source pork from "unusual locations".

The Australian pork industry this month said if the disease broke out in Australia it could cost them up to $2 billion.

A Vietnamese woman was earlier this month deported for failing to declare more than 4.5kg of pork in her luggage, along with squid, quail and eggs.

More than 50 per cent of consumed pork in Australia is imported, but raw pork imports are banned.