While case numbers are currently low – 67 compared to 12 for the same time last year – doctors are worried infections could spiral with the return of international travel, COVID restrictions easing and complacency in the community.

Clinicians are particularly concerned about the potential impact on young children with low immunity having never been exposed to the flu, which has been minimal during the coronavirus pandemic as a result of social distancing, isolation and lack of travel.

Adelaide GP Dr Rod Pearce, who is also chair of the national Immunisation Coalition, said “it’s hard to remember now before COVID but that’s what we used to worry about – we used to get deaths from flu”.

“We still have the same problem – flu can still kill us,” he told InDaily.

The Immunisation Coalition says prior to COVID about 3000 Australians died in a typical influenza year – more than the annual road toll.

“The trouble is we’re not isolating anymore, we’ve got international travel and we haven’t seen the flu for two years,” Pearce said.

“Therefore the response to that is that our immune system is down, we haven’t seen it, we get swamped, and then if COVID is around as well we’ve got two nasty diseases, so that’s the risk this year.

“And there’s some children who’ve never seen flu virus, so we’ve got two-year-olds who haven’t seen it and under fives are a vulnerable age group.”

Pearce said doctors were watching closely what had been occurring in other parts of the world for signs of what might be to come in Australia.

“The northern hemisphere had a lot of flu, the flu went up this winter – COVID came up, so did flu,” he said.

“They had more severe disease both in the UK and the US because there’s a mixture of flu and COVID.”

Pearce said a recent survey of 25,000 Australians conducted by the Immunisation Coalition found that only 40 per cent of South Australians intended to get the flu vaccine this year.

Across the nation, the figure was 42 per cent.

While vaccination rates were even lower last year because of a lack of flu activity, Pearce said “normally this time of the year when we do a survey, we’ll get about 60 or 70 per cent of the population will want to get vaccinated”.

“We’re worried that people won’t actually take the vaccines because they’ve had two years where there’s been no influenza and we did a lot of vaccinating in 2020, wasn’t needed, 2021 it was like ‘who cares’,” Pearce said.

SA Health figures show that as of today, there have been 67 cases of flu in the state compared to 12 for the same time last year.

Case numbers have already topped the total of 40 for the entire 2021 year, when the pandemic was in full swing with borders closed and people socially distancing and wearing masks.

In 2020 – the first year of the pandemic – there were 1583 cases.

That came off the back of a huge flu season in 2019 with 27,093 cases in SA.

“In 2019 we’d been caught short when we didn’t have the vaccines out ready and we started getting outbreaks in nursing homes,” Pearce said.

Learning from past mistakes, the vaccination season was brought forward in 2020.

“Then COVID came, we started getting flu outbreaks, so we panicked and did a whole lot of rapid flu vaccines because we thought we were going to be overwhelmed with that,” Pearce said.

“People started isolating so it dropped down partly because of the vaccination, partly because of the isolation.”

SA Health figures show there have been no flu deaths so far this year, there were none last year, three in 2020 and 120 in 2019.

Pearce said he was nervous about levels of complacency in the community this year.

“If we still wear masks and still socially distance it won’t be too bad but people have forgotten that they haven’t had the flu, they haven’t had that annual boost of coming across the flu, they haven’t had the annual flu vaccine,” he said.

Dr Louise Flood, director of SA Health’s communicable disease control branch, is also concerned about what might happen with flu in SA this year.

“The flu season varies from year to year, and while it is impossible to predict the severity of the season, we may see more cases this year with international travel back on the table, and COVID restrictions easing,” she said.

“Even though flu activity is low so far this year, the flu is still out in the community and numbers could increase at any time.”

Flood and Pearce said the best thing people could do to protect themselves against the flu was to get vaccinated.

“We will be strongly encouraging families with toddlers, to make sure their child has a flu vaccine this year as they may not have been exposed to influenza in the past two years and their immunity will be lower,” Flood said.

“Through the National Immunisation Program, the flu vaccine is free for a number of groups, including pregnant women and all children aged six months to less than five years of age.”

Flood also urged people to “continue practising good hand hygiene, wipe down surfaces, cover coughs and sneezes with a tissue or your arm and stay at home if you’re sick”.