More cases of rockmelon listeria emerge

Two more people have been diagnosed with listeria traced to contaminated NSW rockmelon.

A Victorian man and a Queensland woman are the latest victims of the outbreak, which has now affected 17 people across Australia.

Authorities issued an alert in late February and confirmed last week that three of those people who had been diagnosed had died.

The rockmelon producer in Nericon, near Griffith, voluntarily stopped production after being told of the contamination.

The NSW Food Authority and Berejiklian government came under fire following accusations they took weeks to warn the public after beginning investigations in January.

But NSW Primary Industries Minister Niall Blair hit back, telling ABC's Country Hour there had been no delay and everything was done "by the book".

NSW Health previously defended its response, saying it followed established protocols and takes outbreaks "very seriously".

The NSW Food Authority issued a warning on February 28 as soon as an investigation indicated the rockmelon was the likely source, it said.