Shorten describes poll as a Medicare referendum

The July 2 poll is more a referendum on the future of Medicare than an election, says opposition leader Bill Shorten (pictured).

No one believes you, Malcolm," Mr Shorten told reporters at the Cannington Medical Centre in Perth on Monday.

"When Liberals say 'never ever', get very nervous indeed."

In a quieter moment, Mr Shorten had a quick chat to a mum at the centre, in the seat of Swan.

"We're here today to make sure that we keep talking about saving Medicare, protecting bulk-billing," he told Emily Clarke, whose 14-month-old daughter, Jemima, was having a checkup at the centre.

The flu-infected Mr Turnbull wasn't at the centre, and perhaps should have been, now sounding more like he is auditioning for a remake of The Godfather rather than the prime ministership.

Campaigning in Sydney on Monday, the prime minister told reporters Medicare would never be sold and all aspects of it, including the payments system, would remain public.

"Every element of Medicare services that is currently being delivered by government will continue to be delivered by government, full stop," he said.

Mr Turnbull said the government's own digital transformation office would work to make Medicare services more user-friendly, enable the rollout of smartphone technology and improve doctor transactions.

"But it will all be done within government," he said.

The Liberal Party has also rolled out election posters, signed by Mr Turnbull, which say: "I guarantee Medicare stays.”