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Although Streptococcus pyogenes (Strep A) is the sixth-most common infectious disease globally, its transmission within the household remains an understudied driver of infection. We undertook a systematic review to better understand the transmission of Strep A among people within the home, while highlighting opportunities for prevention. 

This review aims to systematically identify contextual and mechanistic factors that contribute to the success or failure of implementing effective HCs in the prevention and early detection of chronic diseases among Aboriginal and Torres Strait Islander people in Australian primary health care (PHC).

Jonathan Carapetis AM AM MBBS FRACP FAFPHM PhD FAHMS Executive Director; Co-Head, Strep A Translation; Co-Founder of REACH 08 6319 1000 contact@

Streptococcus pyogenes, also known as group A streptococcus (StrepA), is a bacterium that causes a range of human diseases, including pharyngitis, impetigo, invasive infections, and post-infection immune sequelae such as rheumatic fever and rheumatic heart disease. StrepA infections cause some of the highest burden of disease and death in mostly young populations in low-resource settings. Despite decades of effort, there is still no licensed StrepA vaccine, which if developed, could be a cost-effective way to reduce the incidence of disease. 

Scabies is one of the world’s most prevalent diseases, with approximately 147 million cases at any one time and an estimated annual incidence of 455 million new episodes. Although Group A streptococcal (GAS) pharyngitis has long been implicated in the pathogenesis of acute rheumatic fever (ARF) and subsequent rheumatic heart disease (RHD), impetigo caused by GAS has recently been postulated as a link between scabies and the pathogenesis of ARF.

Group A Streptococcus (GAS) causes pharyngitis (sore throat) and impetigo (skin sores) GAS pharyngitis triggers rheumatic fever (RF) with epidemiological evidence supporting that GAS impetigo may also trigger RF in Australian Aboriginal children. Understanding the concurrent burden of these superficial GAS infections is critical to RF prevention. This pilot study aimed to trial tools for concurrent surveillance of sore throats and skins sore for contemporary studies of RF pathogenesis including development of a sore throat checklist for Aboriginal families and pharynx photography.

Controlled human infection (CHI) models can provide insights into transmission of pathogens such as Streptococcus pyogenes (Strep A). As part of the Controlled Human Infection with Penicillin for Streptococcus pyogenes (CHIPS) trial, we explored the potential for transmission among participants deliberately infected with the Strep A emm75 strain.

Knowledge gaps regarding human immunity to Streptococcus pyogenes have impeded vaccine development. To address these gaps and evaluate vaccine candidates, we established a human challenge model of S. pyogenes pharyngitis. Here, we analyse antibody responses in serum and saliva against 19 antigens to identify characteristics distinguishing 19 participants who developed pharyngitis and 6 who did not.

Among genes present in all group A streptococci (GAS), those encoding M-fibril and T-pilus proteins display the highest levels of sequence diversity, giving rise to the two primary serological typing schemes historically used to define strain. A new genotyping scheme for the pilin adhesin and backbone genes is developed and, when combined with emm typing, provides an account of the global GAS strain population.

Streptococcus dysgalactiae subspecies equisimilis and Streptococcus pyogenes share skin and throat niches with extensive genomic homology and horizontal gene transfer possibly underlying shared disease phenotypes.