An alarming number of Strep A infections are going unnoticed throughout classrooms in Broome and Derby according to a major study by The Kids Research Institute Australia aiming to reduce the burden of acute rheumatic fever and rheumatic heart disease.

Published Saturday in PLOS One Global Health, the Missing Piece Surveillance Study found one in six kids living in Western Australia's Kimberley region had Strep A detected at any one time in the throat or skin and, in more than half of cases, there were no noticeable symptoms.

Recurrent, untreated Strep A infections of the throat or skin can lead to acute rheumatic fever (ARF) and rheumatic heart disease (RHD) - life-threatening illnesses that disproportionately affect young Aboriginal and Torres Strait Islander people living in remote areas of Australia and can lead to a reduced life expectancy of around 40 years.

Professor Asha Bowen, Head of the Healthy Skin and ARF Prevention at the Wesfarmers Centre of Vaccines and Infectious Diseases based at The Kids Research Institute Australia, Paediatric Infectious Disease Specialist at Perth Children's Hospital and professor at the University of Western Australia's Medical School, said the study set out to learn more about the missing pieces in the prevention of ARF.

"We set up the Missing Piece Surveillance Study many years ago now, pre-COVID, and what we were trying to understand was the common area of strep infections, both skin sores and sore throats, in children at high risk of rheumatic fever," she told National Indigenous Times.

The focus of the research also included what types of Strep A were causing infections, and what the antibody responses were to the infections.

Professor Bowen said the researchers "chose the Kimberley because it's where the highest rates of rheumatic fever and rheumatic heart disease are in Western Australia, and that's where we work", and noted rates are slightly higher in the Northern Territory.

"We were looking at children that were at risk for rheumatic fever, and we're trying to better understand how strep infections were driving that process. We worked in partnership with schools and the local Aboriginal community-controlled health organisations and conducted the study."

A checklist for spotting the signs of strep

In terms of what was learned that can help counter the spread of strep, researchers developed new ways to quickly identify the need to test for the condition.

"One of the key findings we had in this particular study was that we used a sore throat checklist we developed in partnership with Broome-based mums, aunties and grandmas - people who are looking after small children - and we wanted to make sure the sore throat story for the local area was the same as we might find in Sydney or Melbourne, and we found very common symptoms, so we developed a strep sore throat checklist with them, and then we implemented that, and what we found in the schools was about a third of the children were attending school and had mild sore throat symptoms," Professor Bowen said.

"They might be having a scratchy throat, difficulty swallowing, difficulty eating and drinking and feeling a bit unwell, but they were still coming to school. That's one point for parents - they could use this sore throat checklist and ask their children questions about sore throats, and if they do have any of the symptoms, to take them to clinic to get checked out.

"We're also running a new study which uses that checklist in many of the clinics in Northern Australia now to position some rapid strep tests. So, if people answer yes to any of those questions, they'd have a strep test performed. That's one outcome from the study."

What can families do?

"We found that more kids had low grade symptoms than we're expecting to find, and so parents could be checking to make sure that their kids don't have sore throats, and if they do, taking them to the clinic to get treatment," Professor Bowen told National Indigenous Times.

"We're also looking for skin sores, because that's the other way that strep enters the body, and so doing a quick look for skin sores on your child, especially little ones, when you're giving them a bath at night, or older children, if they're reporting skin sores or sores on their arms or legs, then making sure they get to clinic to get them treated. What we want to do is treat strep infections really early, so we don't see children going on to develop rheumatic fever and then with subsequent episodes developing rheumatic heart disease."

Professor Bowen acknowledged the important work of research partners including the Broome Regional Aboriginal Medical Service and the Derby Aboriginal Health Service, and the participation of the Catholic Education Office of Western Australia through which the researchers were able to work with St Mary's Primary School in Broome and Holy Rosary school in Derby, at which more than 250 children were involved in the study over the course of three years.

"It's really important to acknowledge those service providers, but also those families who got involved in research," she told National Indigenous Times.

"We have also been able to release three children's books which really tell the story of the study, which star some of the children from St Mary's Primary School in Broome in photographs - and they worked on those books with us.

"For people who want to know more, there's that opportunity to go to The Kids Research Institute website and look for those Missing Piece storybooks, and you can download them, or we can provide them as well. Not only did we do science and we worked in partnership with the schools and the clinics, but we also are trying hard to make sure that that's communicated to children and families, so that they have those strategies for prevention."

Strep A more widespread than had been thought

The study saw the analysis of 1000 throat swabs, 200 skin swabs and 400 blood samples, revealing there were significantly more cases of Strep A circulating than first thought.

Using the checklist uniquely developed with Broome families for the Missing Piece Study almost 30 per cent of children coming to school in the Kimberley reported one or more sore throat symptoms, and around 15 per cent of kids had skin sores.

Professor Bowen said the high rate of infection is "certainly concerning, as we know when kids are at school, they pass Strep A around to each other, and we were also able to detect Strep A on some surfaces within the classroom".

"This information provides us with an important opportunity to intervene as there are many things we can do to prevent Strep A, including focusing on hygiene, ensuring children with sore throats are encouraged to go to the clinic for treatment and not sharing close spaces," she said.

Dr Janessa Pickering, lead author and Research Fellow at the Wesfarmers Centre of Vaccines and Infectious Diseases, said the study highlighted that children with Strep A would most likely show no symptoms of infection.

"This is important as asymptomatic Strep A infections have been shown to be a key contributor to Strep A transmission and could be a vital missing link in the global conversation around RHD prevention," Dr Pickering said.

"In addition, we identified that some kids carried the same type of Strep A infection for years, while others never got it at all, which provides us with a path forward for looking at the protective microbiome, or healthy bugs in the throat, that could be potentially guarding some kids against infection."

'We need more investment in RHD prevention'

Derby Aboriginal Health Service CEO Shelley Kneebone said she was very concerned by the number of kids who tested positive but didn't have symptoms.

"The high number of asymptomatic infections is a clear indicator that we need more investment in RHD prevention - it certainly raises the question of how many bouts of Strep A kids are having without being treated," she said.

"I hope the true burden of infection discovered in the study will emphasise the need for greater focus on the social and environmental issues that affect our young children and make them such a high risk of RHD.

"The kids and their families who took part in the study were really supportive of this research, and while the results are worrying, we now have knowledge that can help us plan how we tackle RHD in our communities into the future."