The New South Wales Opposition says the State Government failed to adequately prepare for one of the worst flu seasons on record.
Confirmed influenza cases this season are more than double for the same period last year, with 14,032 recorded cases last month, compared to 4,431 in July last year.
Labor's health spokesman Walt Secord said the outbreak could have been prevented if the State Government encouraged more people to get their flu vaccinations.
"The State Government knew the flu season was coming," Mr Secord said.
"The northern hemisphere had a really bad flu season, they should have prepared a comprehensive plan encouraging people to get their flu vaccinations."
Mr Secord said hospitals were under "enormous pressure" because of additional flu patients attending emergency departments.
"Emergency departments in the state are at breaking point," he said.
"We've had record numbers of people presenting to emergency departments that puts pressure on the entire hospital system."
However, the Australian Medical Association said influenza activity has spiked earlier than previous years.
"The past year has seen a campaign to have flu vaccinations right across the country," AMA vice-president Tony Bartone said.
"The activity is seasonal and may have no bearing on the messaging or the take up of vaccinations."
He said the influenza activity typically peaks in August and September.
"We can only tell if this peak happening now is on the way down or still a sign that things will get worse, in retrospect," he said.
"It's still not too late to have the flu vaccine, it's still not too late to have the best defence against getting influenza."
