The epidemiology of superficial Streptococcal A (impetigo and pharyngitis) infections in Australia: A systematic review

Recovery of culturable Streptococcus pyogenes from swabs stored at different temperatures

Improving our understanding of superficial Streptococcus pyogenes (Strep A) carriage and transmission necessitates robust sampling methods. Here, we compared the effect of storing swab samples in fridge (+4°C) and freezer (-20°C) conditions on the recovery of laboratory-cultured S. pyogenes. Streptococcus pyogenes colony-forming units progressively declined at +4°C, but not at -20°C, over 2 weeks. Results demonstrate that freezing is preferable over refrigeration for storage and transport of skin and throat swabs to ensure that culturing accurately reflects the true results of sampling. This is particularly important in remote community research and practice when immediate incubation is not possible or batch processing is most practical, increasing the elapsed time between collection and laboratory analysis. The study suggests that temperature negatively affects S. pyogenes viability and provides a method to further investigate the role of other environmental factors affecting S. pyogenes transmission.

The heart of the matter: a re-iteration of the role of the social determinants of health in addressing health inequity in Central Australia

The persisting life-expectancy 'gap' between First Nations and non-First Nations Australians is fundamentally driven by the social determinants of health. These include income and social protection, access to adequate housing and food security, among others. These factors are particularly prominent in Central Australia. Inadequate housing has led to some of the highest rates of Streptococcus pyogenes infection in the world, which in turn drives an extremely high prevalence of rheumatic heart disease. Food insecurity and inadequate social protection manifesting as energy insecurity result in inadequate nutrition and have resulted in a huge burden of diabetes in Central Australia. These factors, combined with social exclusion, racism and the pervasive effect of colonisation, also drive a high rate of alcohol misuse. Only by prioritising equity in these 'social determinants' and emphasising the importance of First Nations leadership in formulating and implementing solutions will health inequity be addressed.

Prevalence and Socio-Demographic and Hygiene Factors Influencing Impetigo in Saudi Arabian Children: A Cross-Sectional Investigation

Purpose

To determine the prevalence of impetigo among children in Saudi Arabia as well as to identify socio-demographic factors associated with impetigo.

Methods

This cross-sectional study conducted in Saudi Arabia examined impetigo prevalence and associated factors among children aged 2 to 15. Data collection occurred between June 2022 and November 2023, involving structured interviews with the parents or legal guardians of the participating children. A pre-designed questionnaire was used, which included questions related to personal hygiene practices (such as, frequency of handwashing, bathing routines, and use of communal facilities), environmental conditions, and the child's impetigo diagnosis history.

Results

The study encompassed a total of 1200 participants, with a predominant representation of female (79.3%). Participants exhibited a diverse age distribution, with the highest proportion falling within the 18-24 age group (33.7%). Importantly, a statistically significant association was identified between the occurrence of impetigo in children and their personal hygiene scores (p < 0.001). Children with a confirmed impetigo diagnosis exhibited lower mean personal hygiene scores (2.6 ± 0.723) in contrast to those without such diagnoses (3.75 ± 0.911).

Conclusion

Socio-demographic factors, including child's gender, parental education level, employment status, and geographic location, emerge as significant determinants of impetigo occurrence. Additionally, there is a strong correlation between proper personal hygiene practices and a reduced incidence of impetigo.

Overlapping Streptococcus pyogenes and Streptococcus dysgalactiae subspecies equisimilis household transmission and mobile genetic element exchange

Streptococcus dysgalactiae subspecies equisimilis (SDSE) and Streptococcus pyogenes share skin and throat niches with extensive genomic homology and horizontal gene transfer (HGT) possibly underlying shared disease phenotypes. It is unknown if cross-species transmission interaction occurs. Here, we conduct a genomic analysis of a longitudinal household survey in remote Australian First Nations communities for patterns of cross-species transmission interaction and HGT. Collected from 4547 person-consultations, we analyse 294 SDSE and 315 S. pyogenes genomes. We find SDSE and S. pyogenes transmission intersects extensively among households and show that patterns of co-occurrence and transmission links are consistent with independent transmission without inter-species interference. We identify at least one of three near-identical cross-species mobile genetic elements (MGEs) carrying antimicrobial resistance or streptodornase virulence genes in 55 (19%) SDSE and 23 (7%) S. pyogenes isolates. These findings demonstrate co-circulation of both pathogens and HGT in communities with a high burden of streptococcal disease, supporting a need to integrate SDSE and S. pyogenes surveillance and control efforts.