Cholera in Papua New Guinea: observations to date and future considerations

Cholera is a severe diarrhoeal illness caused by infection with the bacterium Vibrio cholerae. From July 2009 to late 2011 Papua New Guinea (PNG) experienced thefirst outbreak of cholera ever reported in this country. During this time > 15,000 cases of cholera were reported, resulting in approximately 500 deaths. The origin of this outbreak is unknown, but considering the remote location of the initial outbreak an infected international traveller is unlikely to be the source. In this paper we review the characteristics of the PNG cholera outbreak and discuss the ongoing threat of cholera to the country and the region.

Evaluation of a rapid immunochromatographic assay for the detection of rotavirus, norovirus and adenovirus from children hospitalized with acute watery diarrhoea

We evaluated the IP-Triple I immunochromatographic rapid test for the detection of rotavirus, norovirus and adenovirus using stool samples from children with diarrhoea. The detection of norovirus and adenovirus was poor compared to polymerase chain reaction assays. However, high sensitivity (92%) and specificity (99%) were obtained for the detection of rotavirus.

Isolation of Vibrio cholerae and other enteric microbiota from patients

When cholera was first detected in Papua New Guinea (PNG) in mid-2009, national diagnostic capacity faced many challenges. This was in part due to the non-endemic status of the outbreak, resulting in few local staff experienced in Vibrio cholerae detection and poor access to the required consumables. The PNG Institute of Medical Research conducted culture on specimens from suspected cholera patients in Madang Province, with presumptive V. cholerae isolates sent to Goroka for confirmation. Of 98 samples analysed 15 were culture positive, with V. cholerae detected by polymerase chain reaction (PCR) in an additional 3 samples. Further analyses were conducted to identify other pathogenic bacteria from thiosulphate citrate bile salt sucrose (TCBS) agar. Molecular-based assays detected enteropathogenic (n = 1) and enterotoxigenic (n = 1) strains of Escherichia coli. No other major enteric pathogens were detected. The low detection rate of V. cholerae at the provincial level reflects challenges in the laboratory diagnosis of cholera and in-country challenges in responding to an outbreak of a non-endemic disease, such as lack of in-country diagnostic expertise and available consumables in the early stages. It also suggests that full aetiological investigations are warranted in future outbreaks of acute watery diarrhoea in PNG to fully elucidate the potentially complex aetiology, which could in turn guide diagnostic, treatment and prevention measures.