The influenza death of an eight-year-old Melbourne girl has sparked warnings from health authorities about the ongoing seriousness of the 2017 winter flu season.

Rosie Brealey had been sick for a few days with what her family thought was a bad cold, but on Friday she went into cardiac arrest and six paramedics could not revive her.

Her father, Christian Brealey, said his “beautiful princess” Rosie died just hours after she took a turn for the worse.

“She had been sick for a few days and we thought she had a bad cold. Never in my worst dreams did I ever think it would end up like this,” Mr Brealey said in a statement online.

“I’m a walking zombie at the moment … don’t know how we are going to deal with this.”

Her shock death follows the loss of 30-year-old Ben Ihlow who died on Father’s Day, with a Victorian Department of Health spokesperson confirming 95 people had also died in aged care facilities across the state this year.

Health Minister Jill Hennessy said the numbers of those struck down by the flu had doubled.

“People are not just getting the flu, they’re getting very, very sick with the flu,” she said. “Do not underestimate how serious … influenza can be. Don’t dismiss your symptoms.”

According to the federal government’s latest Influenza Surveillance Report, flu rates had gone up more than two-and-a-half times in the year to September 1.

Rosie, eight, did martial arts and Cub Scouts. Photo: Supplied

“There has been more than two and a half times the number of laboratory confirmed notifications of influenza reported to the National Notifiable Diseases Surveillance System (NNDSS) this year when compared with the same period last year,” the report said.

Ms Hennessy couldn’t say if the worst was over.

“We’re not quite sure if the flu season has peaked or not. It is right up the eastern seaboard of Australia,” she said.

Those most likely to be struck down by the flu were those aged 80 or older, followed by young children aged between five and nine-years-old. The median age of deaths was 83.

Map of influenza activity by state and territory, from 22 July – 1 September 2017. Photo: Australian Influenza Surveillance Report

There were 137,566 people diagnosed with the flu up to September 1, according to the report. More than half of those were in New South Wales, while more than 13,000 were in Victoria. The southern and eastern states were the worst affected.

Last year, just 53,159 people had been diagnosed with the flu across the country over the same period, according to the NNDSS.

H3N2, a fast-mutating strain of the flu, has been the predominant strain this season. However, immunisations have been a “moderate to good match” for the circulating strains, the report said.

More than 4.5 million Australians had the flu vaccine this year, Health Minister Greg Hunt said.

Notifications of laboratory confirmed flu from 1 January 2013 to 1 September 2017, by month and week of diagnosis. Photo: Australian Influenza Surveillance Report

in one bright spot, fewer people were hospitalised this year up to September 1. About 8.2 per cent of those diagnosed were admitted to intensive care, compared to 8.7 per cent in 2015 and 14.2 per cent in 2013.

Hospitals this year cancelled elective surgeries to free up beds for those with the flu.

Eight-year-old girl’s tragic death

A GoFundMe page has so far raised more than $4800 for Rosie’s family after she passed away on Friday.

In a statement released to the Herald Sun, Mr Brealey urged people to immunise their children against the flu.

“We are devastated by the loss of our beautiful, loving little angel,” Mr Brealey said. “We urge everyone to get their kids immunised against the flu.”

Rosie took part in Cub Scouts and did martial arts, and attended off-road Jeep events with her family.

Ms Hennessy said her death was “horrifically sad”.

“What it does show us is that we have a horror flu season on our hands,” she said.

The New Daily has contacted the NSW Health Department and the Australian Medical Association for comment.

-with AAP