A Canberra mother of two has died of complications from influenza in what health authorities say is "one of the worst flu seasons on record" in Australia.

Jennifer Thew, from Gungahlin in Canberra's north, died over the weekend after contracting influenza.

Acting chief health officer Dr Andrew Pengilley said to his knowledge the "fit, young" woman was the only young adult in the country who had died from influenza this year.

Ms Thew is also the only person in Canberra to have died from the flu this year.

A Canberra dance school, which Ms Thew's daughter attended, posted a message on Facebook from the family, saying: "Jen was a beautiful, gentle soul and, above all, the most devoted mother".

"We are absolutely heartbroken that she has been taken from us in such cruel circumstances. "We are so grateful to the medical teams in Canberra and Sydney that fought so hard to save her life. "We are also grateful for all the beautiful community support - we have been overwhelmed by all the love. "We are rallying around her husband Ben and their beautiful children."

The dance school also started a Go Fund Me page to raise money for Ms Thew's family.

Rosie Andersen died in the Angliss Hospital at Upper Ferntree Gully in Melbourne's east this month. ( Gofundme )

Victoria has seen a number of deaths due to influenza in the past month, including eight-year-old Rosie Andersen from Melbourne and eight people in an aged care facility in Wangaratta.

Six people also died in a nursing home in Tasmania in September.

A Victorian woman who recently gave birth was also placed in an induced coma earlier this month after contracting influenza while pregnant.

A spokeswoman for the federal Department of Health said there had been 122 flu-related deaths reported nationally as of yesterday, but the true number was likely to be much higher.

ACT influenza reports increase by 140 per cent

Jennifer Thew with her two children in 2014. ( Facebook )

Dr Pengilley said ACT Health had received more than 2,000 notifications of the flu so far this year, compared to about 840 last year.

"The vast majority of those, about 70 per cent, occurred in a four-week period," he said.

"So we've seen both a very large number of cases and it's been a very intense onset."

It is not clear if Ms Thew had been vaccinated.

But Australian National University Professor and infectious diseases physician Peter Collignon said this year the influenza vaccine was not always effective.

"The same strains appear to be circulating here that circulated in Europe and in England last year, and for the elderly for instance, who are most at risk of influenza A and B, the vaccine didn't work at all, it had a minus efficacy," he said.

"Basically it didn't protect you at all for either the A or B strain if you are over the age of 65.

"If you are under the age of 64 you may have had a 30 or 40 per cent protection rate."

Health Minister Meegan Fitzharris said she would receive a more detailed briefing on Ms Thew's death this afternoon.

"We see every year people are really suffering because of the flu, often times that's people who are already more vulnerable in a health sense," she said.

"What we've seen this year, around the country and sadly now here in Canberra, is people that probably weren't in particularly vulnerable groups, who may have caught the flu or influenza and then had further complications."

Ms Fitzharris again urged Canberrans to get a flu vaccine.

"We've certainly seen increased reports of people with the flu and really the flu season isn't over yet either," she said.

"We know that the flu can spread quite easily and ... if you are crook with the flu, you should stay home and you should make sure you not only protect yourself and your family, but others as well."