Four years ago, you may have read that cases of ‘invasive Strep A’ – the potentially lethal and deforming version of the common bacterial infection that also causes tonsillitis – surged over the past four years.

That’s not quite true.

The incidence of invasive Strep A (iGAS) has been steadily increasing over the past two decades worldwide – and led to an increase in deaths, mostly in small children and the elderly.

But the rapid spike in cases happened only a year ago.

This happened to be when most Australians had stopped wearing face masks and were perhaps less diligent in washing their hands.

Two Australian children have died from Strep A in the past year.

Residents of the northern hemisphere suffered a similar surge of invasive Strep A cases at the same time as we did – when many of them had also tired of COVID-19 protection measures.

Are these two events connected?

There was a flattening of cases during 2020 and 2021 when we were washing our hands like maniac clean freaks. So maybe.

But there was also the arrival of a more toxic strain of the bacteria, M1UK. This was discovered in Europe in 2019 and has since been linked with a surge in scarlet fever cases and deaths.

Professor Michael Good, writing at newsGP, says it “seems likely, both in the UK and here, that the main reason we are seeing more cases now is because we are experiencing more respiratory infections across the board as we come out of COVID-imposed isolation, especially from influenza”.

Co-infection with influenza and Strep A, he writes, can render both infections significantly more dangerous and difficult to control.

So there appears to be multiple factors at play.

What is Strep A?

Otherwise known as Group A Streptococcal (GAS) infection, Strep A commonly causes mild illnesses such as tonsillitis, pharyngitis, impetigo, cellulitis and scarlet fever.

However, in rare instances, when left untreated, Strep A can cause life-threatening conditions, including ‘invasive’ strep A disease (iGAS) and rheumatic heart disease, which is the most commonly acquired heart disease in people younger than 25.

There has been an increase in scarlet fever cases in children. Photo: Getty

According to a newsGP article penned by Professor Good, invasive disease occurs “when an otherwise simple infection of the tonsils or skin spreads beyond the local tissue and invades deep tissue”.

From there it can spread to distant sites in the body, leading to shock, potential loss of limbs, and death.

Severe symptoms include sepsis (blood poisoning), streptococcal toxic shock syndrome (which can lead to multiple organ failure and death), necrotising fasciitis (also known as ‘flesh-eating disease’), pneumonia, and inflammation of the kidneys.

Strep A infections disproportionately affect young children, the elderly, pregnant women and Indigenous Australians.

Rates of acute rheumatic fever and rheumatic heart disease among Indigenous populations in northern Australia are some of the highest in the world. It’s a crisis rarely discussed.

What’s the story in Australia?

In a new paper, researchers from the Murdoch Children’s Research Institute investigate the epidemiology of invasive Strep A among Australian children from July 2018 to December 2022.

The Paediatric Active Enhanced Disease Surveillance (PAEDS) Network prospectively collected iGAS patient notifications for children and young people aged less than 18 years admitted to five major Australian paediatric hospitals in Victoria, Queensland, Western Australia and the Northern Territory.

The researchers identified 280 reported cases of severe Strep A in children aged under 18. The median age of the patients was 4.5 years.

There were three attributable deaths over the four-year period and 84 (32 per cent) patients had severe disease.

The paper is essentially an argument for greater investment in the development of a vaccine.

The researchers describe the surge in infections as “intense”.

It’s important to note that invasive infections are still rare.

In 2018, the incidence of invasive strep A was 3.7 cases per 100,000 among children in Australia.

In the third quarter of 2022 it was 5.2 per 100,000 children in the third quarter of 2022.

There were 23 cases in children in 2020, compared to 107 in 2022.

When did this first make news?

In December, The New Daily reported that a string of Strep A-related deaths in the UK had prompted Victorian health authorities to issue a warning that severe infections of the bacteria were on the rise.

News of the spike were reported over the next couple of months. And probably made no impact on the populace.

Last week, Queensland health authorities warned that children infected with Strep A were at risk of developing scarlet fever. Parents were urged to check their children for fever and rash symptoms.

The call for a vaccine made news again this week.

Vaccine candidates being tested

Murdoch Children’s Professor Andrew Steer, in a prepared statement, said the study found more children were presenting with severe symptoms as a result of Strep A infections.

“More research is required into the causes of this spike and how we can prevent future surges,” he said.

“With ongoing funding, we can begin to answer some of these complex questions and work towards an effective and accessible Strep A vaccine.”

Professor Steer and his team are testing candidate Strep A vaccines developed by researchers in Australia and overseas in a first-of-its-kind human challenge model.

The trials are planned to be conducted in Melbourne, involving about 50 participants. They’ll receive a candidate vaccine or placebo and have Strep A applied on their throats in a controlled environment.

“We hope this research will accelerate the development of a vaccine and move things forward to bigger field trials,” Professor Steer said.

He said a vaccine for Strep A will save hundreds of thousands of lives every year.

What to do

In the meantime: Be vigilant and seek treatment for common Strep A infection.

Start washing those hands with pandemic-like diligence. It should be an everyday habit regardless of this outbreak or others.

Soap and water should help keep you and your children safe from a range of infections.