Scabies and risk of skin sores in remote Australian Aboriginal communities: A self-controlled case series study

Abstract

BackgroundSkin sores caused by Group A streptococcus (GAS) infection are a major public health problem in remote Aboriginal communities. Skin sores are often associated with scabies, which is evident in scabies intervention programs where a significant reduction of skin sores is seen after focusing solely on scabies control. Our study quantifies the strength of association between skin sores and scabies among Aboriginal children from the East Arnhem region in the Northern Territory.Methods and resultsPre-existing datasets from three published studies, which were conducted as part of the East Arnhem Healthy Skin Project (EAHSP), were analysed. Aboriginal children were followed from birth up to 4.5 years of age. Self-controlled case series design was used to determine the risks, within individuals, of developing skin sores when infected with scabies versus when there was no scabies infection. Participants were 11.9 times more likely to develop skin sores when infected with scabies compared with times when no scabies infection was evident (Incidence Rate Ratio (IRR) 11.9; 95% CI 10.3–13.7; p<0.001), and this was similar across the five Aboriginal communities. Children had lower risk of developing skin sores at age ≤1 year compared to at age >1 year (IRR 0.8; 95% CI 0.7–0.9).ConclusionThe association between scabies and skin sores is highly significant and indicates a causal relationship. The public health importance of scabies in northern Australia is underappreciated and a concerted approach is required to recognise and eliminate scabies as an important precursor of skin sores.

Ending rheumatic heart disease in Australia: the evidence for a new approach

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Control Strategies for Scabies

“…Fourth, there is limited evidence to determine the magnitude of the association between scabies and its complications. Available epidemiologic data suggest that, in highly endemic settings, at least 40% of impetigo lesions can be attributed to scabies, and an even higher proportion among younger children (71% in one study) [ 17 , 20 , 21 , 22 ]. The high attributable risk observed in epidemiologic studies is supported by trials of community control of scabies, as outlined below, where impetigo prevalence has been shown to fall consistently and substantially with reductions in scabies prevalence.…”

Acute kidney injury in Indigenous Australians in the Kimberley: age distribution and associated diagnoses

“…We found that skin infections were among the most frequent principal diagnoses for Indigenous people in the Kimberley with an AKI event; in the national data, in contrast, the top ten diagnostic categories of principal diagnoses for hospitalisations in which AKI was an additional diagnosis did not include skin conditions . A large burden of skin disease in Indigenous Australians has been reported, but mainly in children; we found that the negative impact of skin infections extends into adulthood. Indigenous communities with housing problems and overcrowding as environmental risk factors are more likely to report skin conditions as health problems, and streptococcal skin infections are associated with acute post‐infectious glomerulonephritis and CKD .…”