There were more than 11,200 cases in July alone, compared with 4431 in July 2016. In the past week there had been 2000 more cases than the same week last year. Hospitals in western Sydney, northern Sydney, Nepean-Blue Mountains and North Sydney were the hardest hit, and had the highest rates of flu in the state. Western Sydney Local Health District emergency departments alone recorded 2428 confirmed cases in July. Close to 140 influenza outbreaks had been reported in NSW nursing homes so far this year, and more than 50 outbreaks in the past week alone.

A total of 34 deaths were linked to influenza outbreaks among nursing home residents, all of whom had other significant health problems. Most of the nursing home outbreaks would have started with an unwell family member or friend bringing their flu symptoms with them when they came to visit, NSW Health Director of Communicable Diseases Vicky Sheppeard said. People with elderly relatives were risking the life of their loved one if they visited them while they were unwell with flu symptoms, Dr Sheppeard said. "Each year more than 800 people die in NSW from complications associated with influenza and the elderly are particularly vulnerable," she said.

"We are seeing high levels of both influenza A and B strains circulating in the community and older people are more susceptible to severe infection from the influenza A strain that is circulating." Labor health spokesman Walt Secord criticised the NSW government's efforts to prepare for the flu season, saying it should have prepared a comprehensive plan to urge families to get vaccinated against the flu, and ensuring there were enough staff rostered on at emergency departments to prevent bed block. "Every year we know the flu season is coming and, again, the state government has been caught off guard. They have dropped the ball on prevention," Mr Secord said. "Due to the state government's failure to properly prepare, the additional flu patients in emergency departments mean other patients have to wait longer. "The last thing the NSW health and hospital system needs is to see hundreds of extra patients pouring into emergency departments with preventable flu symptoms."

NSW Health said it was managing the influx. It is understood people with flu-like symptoms may be presenting at emergency departments rather than GPs in greater numbers than previous years. The department has repeatedly released alerts urging eligible members of the public, including those with chronic conditions, to take advantage of the free flu vaccine, and renewed its call on Tuesday for all elderly people and those in high-risk groups to get vaccinated. Pregnant women were also strongly advised by NSW Health to get the flu vaccination to reduce the risk to themselves and their babies. "During peak times we encourage people to seek advice from their GPs and HealthDirect, a 24-hour helpline that provides immediate health advice online from registered nurses," Dr Sheppeard said.

Flu symptoms include fever and chills, coughs, sore throats and runny or stuffy noses, muscle aches and joint pains, headaches and fatigue, and nausea, vomiting and diarrhoea.