Until recently cholera had never been reported in Papua New Guinea despite the close proximity of cholera-endemic countries and the presence of environmental and social characteristics that are considered risk factors for cholera outbreaks. The current outbreak began in July 2009 and rapidly spread throughout the coastal regions of the country. Initial characterization studies using variable-number tandem repeat analysis indicate that the outbreak was a recent clonal incursion from South-East Asia. By mid-2011 the outbreak had resulted in the reporting of more than 15 500 cases of cholera and over 500 deaths: a case fatality ratio (CFR) of approximately 3.2%. Following an outbreak of cholera, interventions such as the introduction of oral rehydration therapy aim to reduce the CFR to below 1%. This elevated CFR is likely a reflection of the inaccessibility of much of the country, the lack of health care services available in remote regions and the general unpreparedness for an outbreak of this kind. This premise is supported by the differences in CFRs between the relatively well-serviced National Capital District (0.1%) and more remote regions such as the Western Province (8.8%).

Arboviruses (arthropod-borne viruses) are important emerging pathogens in many tropical and developing countries of the world. The Southeast Asian and Western Pacific regions have recently experienced large outbreaks of dengue, Japanese encephalitis and chikungunya fever. In Papua New Guinea (PNG) serological surveys and mosquito isolation experiments suggest that arboviruses are prevalent throughout the country. However, the lack of surveillance and clinical reporting means that the distribution and prevalence of these diseases is unknown. In this paper we review the most important arboviruses with regard to human health in the PNG region.

The Oceania region, which includes Australia, New Zealand, Papua New Guinea and the islands of the tropical Pacific Ocean, has historically been free from chikungunya. However, the 2011 outbreak in New Caledonia and the ongoing outbreak in Papua New Guinea have highlighted the risk to other communities in Oceania where there are competent mosquito vectors and permissive social factors and environmental conditions. In this article we discuss the threat to this region that is posed by the recent evolution of the E1:A226V mutant strains of chikungunya virus (CHIKV).

Cholera was first detected in Papua New Guinea in July 2009, caused by Vibrio cholerae O1 El Tor serotype Ogawa. By late 2011, 15 500 cases had been reported throughout lowland Papua New Guinea with a case fatality rate of 3.2%. The epidemic has since slowed, with only sporadic cases reported in Western Province and the Autonomous Region of Bougainville (ARB). Accurate and timely diagnosis is a critical element of the public health response to cholera, yet in low-income countries where the burden of cholera is the greatest, diagnostic services are often limited. Here we report on the diagnostic challenges and the logistical factors that impacted on diagnosis during the first reported outbreak of cholera in Papua New Guinea.

We investigated the circulation of avian influenza viruses in poultry populations throughout Papua New Guinea to assess the risk to the poultry industry and human health. Oropharyngeal swabs, cloacal swabs and serum were collected from 537 poultry from 14 provinces of Papua New Guinea over an 11–month period (June 2011 through April 2012). Virological and serological investigations were undertaken to determine the prevalence of avian influenza viruses. Neither influenza A viruses nor antibodies were detected in any of the samples. This study demonstrated that avian influenza viruses were not circulating at detectable levels in poultry populations in Papua New Guinea during the sampling period. However, avian influenza remains a significant risk to Papua New Guinea due to the close proximity of countries having previously reported highly pathogenic avian influenza viruses and the low biosecurity precautions associated with the rearing of most poultry populations in the country.

Objective:The objective of this study was to investigate a large outbreak of shigellosis in Papua New Guinea that began in a camp for internally displaced persons before spreading throughout the general community.Methods:Outbreak mitigation strategies were implemented in the affected area to curtail the spread of the disease. Data were collected from the surveillance system and analysed by time, place and person. Rectal swab samples were tested by standard culture methods and real-time polymerase chain reaction to determine the etiology of the outbreak.Results:Laboratory analysis at two independent institutions established that the outbreak was caused by Shigella sp., with one strain further characterized as Shigella flexneri serotype 2. Approximately 1200 suspected cases of shigellosis were reported in a two-month period from two townships in Morobe Province, Papua New Guinea. The outbreak resulted in at least five deaths, all in young children.Discussion:This outbreak of shigellosis highlights the threat of enteric diseases to vulnerable populations such as internally displaced persons in Papua New Guinea, as has been observed in other global settings.

Objective: To establish seasonal and alert thresholds and transmission intensity categories for influenza to provide timely triggers for preventive measures or upscaling control measures in Cambodia. Methods: Using Cambodia’s influenza-like illness (ILI) and laboratory-confirmed influenza surveillance data from 2009 to 2015, three parameters were assessed to monitor influenza activity: the proportion of ILI patients among all outpatients, proportion of ILI samples positive for influenza and the product of the two. With these parameters, four threshold levels (seasonal, moderate, high and alert) were established and transmission intensity was categorized based on a World Health Organization alignment method. Parameters were compared against their respective thresholds. Results: Distinct seasonality was observed using the two parameters that incorporated laboratory data. Thresholds established using the composite parameter, combining syndromic and laboratory data, had the least number of false alarms in declaring season onset and were most useful in monitoring intensity. Unlike in temperate regions, the syndromic parameter was less useful in monitoring influenza activity or for setting thresholds. Conclusion: Influenza thresholds based on appropriate parameters have the potential to provide timely triggers for public health measures in a tropical country where monitoring and assessing influenza activity has been challenging. Based on these findings, the Ministry of Health plans to raise general awareness regarding influenza among the medical community and the general public. Our findings have important implications for countries in the tropics/subtropics and in resource-limited settings, and categorized transmission intensity can be used to assess severity of potential pandemic influenza as well as seasonal influenza.

Diarrhoeal diseases still affect many people, especially children living in impoverished and under-developed settings. In Papua New Guinea (PNG) diarrhoea remains one of the leading causes of hospitalization and a major cause of death. Here, we focus on the role of Shigella in diarrhoeal illness in PNG, and provide an overview of the causative organism and the illness. A review of the available data on the aetiology of diarrhoea in PNG suggests that shigellosis is a major cause of diarrhoeal illness. Since shigellosis can cause protracted and life-threatening illness an appreciation of the burden of shigellosis is important to aid in the development of optimal prevention and control strategies. Treatment strategies for all cases of moderate-severe diarrhoeal illness should centre on rehydration, but where antimicrobial treatment is required consideration should be given to the increasing antimicrobial resistance observed in Shigella isolates in PNG.
Shigellosis ; Diseases ; Infection prevention

Abstract Diarrhoeal diseases are among the leading causes of morbidity and mortality in the Western Pacific Region. However, data on the major causes of infectious diarrhoea are limited in many countries within the Region, including Papua New Guinea. In 2013–2014, we conducted surveillance for acute diarrhoeal illness in four provinces in Papua New Guinea. One rural health clinic from each province participated in the surveillance activity. Samples were sent to central laboratories and batch analysed for bacterial and viral gastrointestinal pathogens that are commonly associated with diarrhoea. Across the four sites, the most commonly detected pathogens were Shigella spp., Campylobacter spp. and rotavirus. In this paper, we report the results of the surveillance activity and the challenges that we faced. The lessons learnt may be applicable to other parts of the Region with a similar socioeconomic status.