Melioidosis in Papua New Guinea and Oceania

Melioidosis has only been sporadically reported throughout Melanesia and the Pacific region since the first report from Guam in 1946; therefore, its contribution to the disease burden in this region is largely unknown. However, the outcome of a small number of active surveillance programs, serological surveys, and presumptive imported cases identified elsewhere provide an insight into its epidemiology and potential significance throughout the region. Both clinical cases and environmental reservoirs have been described from the rural district of Balimo in the Western Province of Papua New Guinea and from the Northern Province of New Caledonia. In both these locations the incidence of disease is similar to that described in tropical Australia and Burkholderia pseudomallei isolates are also phylogenetically linked to Australian isolates. Serological evidence and presumptive imported cases identified elsewhere suggest that melioidosis exists in other countries throughout the Pacific. However, the lack of laboratory facilities and clinical awareness, and the burden of other infections of public health importance such as tuberculosis, contribute to the under-recognition of melioidosis in this region

Intensity of Rainfall and Severity of Melioidosis, Australia

In a 12-year prospective study of 318 culture-confirmed cases of melioidosis from the Top End of the Northern Territory of Australia, rainfall data for individual patient locations were correlated with patient risk factors, clinical parameters, and outcomes. Median rainfall in the 14 days before admission was highest for those dying with melioidosis (211 mm), in comparison to 110 mm for those surviving (p = 0.0002). Median 14-day rainfall was also significantly higher for those admitted with pneumonia. On univariate analysis, a prior 14-day rainfall of ≥125 mm was significantly correlated with pneumonia (odds ratio [OR] 1.70 [confidence interval [CI] 1.09 to 2.65]), bacteremia (OR 1.93 [CI 1.24 to 3.02]), septic shock (OR 1.94 [CI 1.14 to 3.29]), and death (OR 2.50 [CI 1.36 to 4.57]). On multivariate analysis, rainfall in the 14 days before admission was an independent risk factor for pneumonia (p = 0.023), bacteremic pneumonia (p = 0.001), septic shock (p = 0.005), and death (p < 0.0001). Heavy monsoonal rains and winds may cause a shift towards inhalation of Burkholderia pseudomallei

Infectious diseases in Northern Australia

[Extract] This issue of Microbiology Australia covers biomedical research and workforce training in Northern Australia and our northern neighbouring countries. The north of Australia is a tropical region and has a larger representation of Australian First Nations peoples than other States and Territories of Australia. In Australia, Aboriginal and Torres Strait Islander people represent 3.2% of the total Australian population. However, in the Northern Territory, the Australian census (2021) shows that approximately 26.3% of the total population identify as Aboriginal and Torres Strait Islander. This underpins the need for Northern Australia to have continued funding to enable health research, workforce training and health and community services that address the currently unmet and still growing needs of this population demographic

First documentation of in vivo and in vitro ivermectin resistance in Sarcoptes scabiei

Ivermectin is increasingly being used to treat scabies, especially crusted (Norwegian) scabies. However, treatment failures, recrudescence, and reinfection can occur, even after multiple doses. Ivermectin resistance has been documented for some intestinal helminths in animals with intensive ivermectin exposure. Ivermectin resistance has also been induced in arthropods in laboratory experiments but, to date, has not been documented among arthropods in nature. We report clinical and in vitro evidence of ivermectin resistance in 2 patients with multiple recurrences of crusted scabies who had previously received 30 and 58 doses of ivermectin over 4 and 4.5 years, respectively. As predicted, ivermectin resistance in scabies mites can develop after intensive ivermectin us