But experts are warning that the peak of flu season might not have yet hit.

According to Department of Health and Human Services figures, the City of Greater Bendigo has recorded 64 cases of influenza this year, up from 22 last year and 12 in 2013.

Half of these have been reported in the past three weeks.

Dr Alan Hampton, of the Influenza Specialist Centre, has warned the peak would likely arrive in September.

"We're on the cusp of the peak at the moment," he said.

More than 6000 Victorians have been struck down by the influenza virus so far this year, almost treble the number in 2013 (2373).

The outbreak has been exacerbated by a particularly harsh winter in most parts of the state, including central Victoria.

Eaglehawk Medical Group's Dr Talitha Barrett said there had been a notable rise in the number of people presenting with influenza or flu-like symptoms.

"We feel there is more this year, but that's not based on any particular statistics," she said.

"There's a lot more testing done, so there's a lot more being detected.

"There's certainly been plenty of whooping cough around, particularly in schools, and also lots of pneumonia going around."

Dr Barrett said good hygiene and avoiding sick people and crowds were the best ways to avoid the flu at this point of the season.

The Bendigo Advertiser last week reported Bendigo was experiencing its worst winter for whooping cough in many years.

A total of 82 people have been hit by whooping cough, more than three and a half times the 2014 amount.

The influenza impact has been felt at the Bendigo Blood Bank, which has experienced a shortfall of donations this winter.

Blood service community relations officer Shae Smith said 28 per cent of donors had cancelled appointments during the past three months, mainly due to flu and cold symptoms.

She said the late peak in flu season had spurred a need for more than 300 appointments at the centre during September.

"People who have had the cold or flu need to be system free for one week before they can donate," Ms Smith said.

THE flu jab doesn't just keep the virus away, it can reduce the risk of a heart attack for people over 50.

The risk is reduced by 29 per cent when compared to those who haven't been vaccinated, according to a UNSW study published in the journal Heart.

That's in the same ballpark as other heart attack preventative measures such as stopping smoking, anti-hypertensive medications and statins, says senior author Professor Raina MacIntyre.

"This is another method that could be added to the mix and it's cheap, effective and safe," she told AAP.

The vaccine is free for Australians aged 65 and over.

But Prof MacIntyre said a cost-effectiveness study should now investigate if it should be extended to people 50 and over - 50 being the start of the at-risk age group for heart attacks.

"The study should include the benefit of preventing heart attacks in a proportion of people," she said.

Heart disease is the leading cause of death in the world and carries an enormous cost burden.

Around 54,000 Australians suffer a heart attack every year and 8611 died from a heart attack in 2013.

The UNSW researchers conducted a systematic review and meta-analysis of 16 international case control studies to estimate the association of influenza and vaccination with heart attacks.

It confirmed their 2013 study which found the jab could lower the risk of a heart attack by 45 per cent.

They also found a strong link between the flu and heart attacks.

"If you have had influenza your risk of heart attack is doubled in the immediate time frame after having it," Prof MacIntyre said.

Previous research indicates that infections such as the flu might encourage blood to thicken or prompt an inflammatory response in arteries that are already diseased, and trigger a blockage in a partially blocked artery.

"Even if you're a healthy weight and you've no family history of heart attacks, you may have some thickening of your arteries without knowing it," she said.

"Based on this study's findings, I would recommend the flu jab for anyone over 50 regardless if they are at risk of heart disease."

- AAP