A review of diarrhoea aetiology in Papua New Guinea, 1995-2012.

The large contribution of diarrhoea to morbidity and mortality rates in Papua New Guinea (PNG) warrants a significant response to diagnosing aetiology, determining appropriate management and reducing risk factors that facilitate transmission of enteric pathogens. We conducted a review of literature to assess the extent of research published on the aetiology of diarrhoea in PNG between 1995 and 2012. Of 54 peer-reviewed articles that were selected for review, 25 pertained to aetiology. While the majority of articles described typhoid fever and non-typhoid salmonellosis, shigellosis, rotavirus, pigbel and cholera were also represented in the literature reviewed.

Antibiotic resistant Shigella is a major cause of diarrhoea in the Highlands of Papua New Guinea.

INTRODUCTION: Diarrhoea remains a major cause of illness in Papua New Guinea (PNG); however, little is known about its aetiology. As a result of the cholera outbreak that spread throughout PNG in 2009-2011, we conducted diarrhoeal surveillance in Eastern Highlands Province. METHODOLOGY: Following informed consent and a brief questionnaire, participants provided a stool sample or duplicate rectal swabs. Samples were tested for common bacterial pathogens Salmonella spp., Shigella spp., Vibrio spp., Campylobacter spp. and Yersinia enterocolitica using established culture methods. Enteric parasites were detected using microscopy. RESULTS: A total of 216 participants were enrolled; where age was recorded, 42% were under 5 years of age, 6.7% were 5 to 17 years of age and 51.3% ≥18 years of age. One or more pathogens were detected in 68 (31.5%) participants, with Shigella (primarily S. flexneri) being the most commonly isolated (47 of 216 participants). Enteric parasites were detected in 23 of the 216 participants, occurring as a co-infection with another pathogen in 12 of 23 cases. No Vibrio cholerae was detected. Shigella isolates were commonly resistant to ampicillin, tetracycline, co-trimoxazole and chloramphenicol. CONCLUSIONS: Shigellae, specifically S. flexneri, are important pathogens in the highlands of PNG. While most studies in low-income settings focus on childhood aetiology, we have demonstrated the importance of Shigella in both children and adults. Enteric parasites remain present and presumably contribute to the burden of gastrointestinal illness. While improvements in sanitation and hygiene would help lower the burden of all aetiologies of infectious diarrhoea, additional control strategies targeting Shigella may also be warranted.