Scientists have warned that Australia could be importing superbugs in its food supply because of China's rampant use of antibiotics on farms.

US scientists say antibiotics are in such heavy use on Chinese animal farms that it could lead to wide human antibiotic resistance on a vast scale.

A research team from Michigan State University carried out tests on manure from three large commercial pig farms in China.

The researchers discovered large concentrations of genes which are capable of conferring resistance to all major classes of antibiotics.

Those genes are being dispersed into the soil as the manure is re-used as fertiliser.

"While we don't import any fresh meats ... that effluent and that water is used to grow, for instance, vegetables and other items that we do import from China," Professor Peter Collignon, infectious diseases expert from the Australian National University said.

"So there is an issue that ... what happens in China can affect us, not only when people visit there and eat food and drink water there that may be contaminated, but even what we import into this country may be contaminated with that material or superbugs - and currently we have no way of testing for that."

Professor Collignon added that the only way to ensure that fresh food in Australia carries as little risk as possible is to review the monitoring system used for the importation of food.

"We need to do a lot more than we're doing now," he continued.

"We have poor monitoring of what superbugs are in both domestically and imported food.

"There is no point in having really good quality foods here and enforcing better rules ... if we then allow imports that don't have those same restrictions."