Papua New Guinea Research Articles

“Sanguma Em I Stap” (Sanguma Is Real)

In Papua New Guinea (PNG), citizenship rests on one’s capacity to translate oneself. Political participation takes place in cultural contact zones, and public discourse circulates only when people create interfaces between disparate languages, systems of knowledge, and values. Yet these translations are not treated equally in mass print media. The uniquely ethnographic citizenship of PNG demands that people decide how their social identities relate to their political agency yet without a guarantee that their solutions will be validated. Just as the national creole language Tok Pisin is subject to competing ideological evaluations of multilingualism, Tok Pisin public discourse is characterized by competing tendencies toward epistemic inclusion and exclusion, particularly when sorcery and other occult topics are discussed. In each case, discussion of the occult involves both an openness to differences in knowledge and a tendency to treat particular knowledge claims as beliefs (bilip) to be overcome. While bilip has become the dominant way to constrain public discourse on the occult, I also show that the bilip can be reinterpreted to index a moral stance of mutual recognition of differences.

National-Scale Geochemical Baseline and Anomalies of Chromium in Papua New Guinea

Papua New Guinea (PNG) is located at the convergence edge of the Pacific Plate and the Indo-Australian Plate, consisting of three units. There are three chromium mineralization types in PNG. Based on national-scale geochemical mapping in PNG during 2015–2018, 1399 samples of stream sediments were collected from Highland Region, Papua Peninsula, and New Guinea Islands. This paper preliminarily studied chromium’s geochemical background, spatial distribution characteristics, and geochemical anomalies. The chromium concentration ranged from 3 ppm to 74,600 ppm, with a median value of 145 ppm, which was higher than the upper crustal abundance of chromium and the chromium geochemical baseline of Europe, Australia, North America, and China. In terms of stream sediment samples in different tectonic units, as mafic–ultramafic magmatic rocks are widely developed, the median chromium values of the New Guinea Orogen, including the Papuan Fold Belt, the New Guinea Thrust Belt, the Finisterre Terrane, the Aure Fold Belt, the Eastern Fold Belt, and the Eastern Papuan Composite Terrane, were higher than the value of the Melanesian Arc. The ophiolitic complexes, such as the April ophiolite, the Marum ophiolite, and the Papua ultramafic belt, significantly correlated with the higher chromium concentration. Eleven chromium high anomalies with mineralization potential were delineated, including three laterite and podiform prospecting areas and eight placer prospecting areas. Based on the chromium–nickel integrated anomaly map, comprehensive exploration and exploitation of nickel and chromium can be carried out in 1 and 11 high anomaly areas related to lateritic mineralization.

Prevalence of Barmah Forest Virus, Chikungunya Virus and Ross River Virus Antibodies among Papua New Guinea Military Personnel before 2019.

Barmah Forest virus (BFV), Chikungunya virus (CHIKV) and Ross River virus (RRV) belong to the Alphavirus genus of the family Togaviridae. All three virus infections have been reported in Papua New Guinea (PNG) previously, but the exact prevalence and distribution of these three alphaviruses in PNG has not been established. Sera collected from 204 PNG Military Personnel (PNGMP) study participants in April 2019 was tested for the presence of anti-BFV, anti-CHIKV and anti-RRV immunoglobulin G (IgG) antibodies using commercially available enzyme-linked immunosorbent assay (ELISA) IgG detection kits, as well as for specific neutralizing antibodies (NAb) against individual viruses. Overall, sero-positivity of the sera was anti-BFV IgG 12.3% (25/204), anti-BFV NAb 8.3% (17/204); anti-CHIKV IgG 47.1% (96/204), anti-CHIKV NAb 34.8% (71/204); and anti-RRV IgG 93.1% (190/204), anti-RRV NAb 56.4% (115/204), respectively. Of the 137/204 participants that were Nab-positive for at least one virus, we identified 4 BFV, 40 CHIKV and 73 RRV single infections, and 9 RRV+CHIKV and 11 BFV+RRV double infections. The lower proportion of NAb sero-positive compared to the ELISA IgG sero-positive assay samples suggests that the currently available commercial ELISA detection kits for these three alphaviruses may not be suitable for diagnostic/surveillance purposes in endemic areas such as PNG, due to serological cross-reactivity among these three alphaviruses. Laboratory testing using known positive control sera indicated no cross-neutralization between BFV and RRV; however, some RRV or BFV single infection human sera demonstrated low-level cross-neutralization against CHIKV (the ratio of RRV/CHIKV NAb titers or BFV/CHIKV ≥ 4). Our preliminary results indicate that the majority of PNGMP have previously been exposed to RRV, with mild exposure to CHIKV and low-level exposure to BFV, suggesting that multiple alphaviruses have been circulating among PNGMP. The transmission landscapes of these three alphaviruses across PNG should be prioritized for further investigation, including identification of specific vectors and hosts that mediate human spillover in order to mitigate future outbreaks. Ongoing education regarding precautionary and protective measures are needed to better protect individuals who travel to PNG.

The impacts of a culturally relevant book flood on early literacy in Papua New Guinea

Determining the most effective means to improve literacy rates in low resource educational environments remains an important challenge. We explored literacy impacts of a book flood of culturally relevant reading books in Papua New Guinea (PNG) through teacher training and distributing 25,240 copies of 126 culturally relevant books to 150 schools. The project also included 150 control schools. We sampled Elementary 1 and 2 level cohorts in 79 schools at baseline and 79 Elementary 2 level schools at follow up - over 1,100 children at each stage - and found statistically significantly greater improvements in the intervention group’s reading comprehension. Our analysis indicates that the flood of culturally relevant books was the principal reason.

Assessment of indium prospecting potential in national-scale geochemical perspective, Papua New Guinea

The spatial distribution and statistics of indium in stream sediments from Papua New Guinea (PNG) were studied based on the results of Papua New Guinea National-Scale Geochemical Baseline (PNG-NGB) project (2015–2018). 1399 samples were collected covering approximately 128,000 km2 with sample density of approximately 1.1 site/100 km2. Indium concentration in the stream sediments of PNG ranged from 0.003 μg/g to 0.24 μg/g with a baseline (median) value of 0.067 μg/g, a value of slightly higher than the upper crustal abundance of indium and Europe, North America, Australia and China. 64 indium anomalies are decided by cumulative – frequency method and contrast value, 39 anomalies are associated with porphyry, VMS, skarn, bauxite, and epithermal deposits and occurrences while porphyry and VMS mineralization is the most important type for indium prospecting and exploration. Parent rock type is also an important factor that controls the geochemical pattern of the indium distribution in stream sediments of PNG.

Testing Geology with Biology: Plate Tectonics and the Diversification of Microhylid Frogs in the Papuan Region.

Studies of the Papuan region have provided fundamental insights into the evolutionary processes generating its exceptional biodiversity, but the influence of geological processes merits further study. Lying at the junction of five tectonic plates, this region has experienced a turbulent geological history that has not only produced towering mountains allowing elevational specialization and island archipelagos with varying degrees of isolation promoting vicariance, but also active margins where land masses have collided and been subsequently rifted apart creating a mosaic of intermixed terranes with vastly different geological histories. Asterophryine frogs are a hyperdiverse clade representing half the world's microhylid diversity (over 360 species) centered on New Guinea and its satellite islands. We show that vicariance facilitated by geological history explains this far and wide distribution of a clade that should have poor dispersal abilities. We recovered a mainland tectonic unit, the East Papua Composite Terrane (EPCT), as the center of origin for Asterophryinae and no fewer than 71 instances of what appear to be long-distance dispersal events, 29 of which are between mainland regions, with 42 from the mainland to the islands, some presently as far as 200km away from source populations over open ocean. Furthermore, we find strong support for a "Slow and Steady" hypothesis for the formation of the northern margin of New Guinea by many separate accretion events during the Miocene, over other major geological alternatives, consistent with the 20M year age of the clade and arrival via the EPCT. In addition, the historical biogeography of our frogs strongly supports an affiliation of the Louisiade Archipelago and Woodlark Island with the Owen Stanley Range on the EPCT, and the recent proximity of the large New Britain Island. Our results show that Asterophryinae did not have to repeatedly and independently disperse across large ocean barriers to the offshore islands, against the predictions of island biogeography theory, but that the current distribution can be explained through vicariance and short-distance oceanic dispersal as historical land connections disappeared and islands slowly became separated from each other. We show that islands have a life history, changing in distance from other land masses, with consequent opportunities for dispersal, isolation, and cladogenesis of their biotas. More broadly, we can begin to see how the geological history of the Papuan region can result in the rapid accumulation and staggering number of extant species.

Challenges of establishing an emergency medical team in Papua New Guinea.

Papua New Guinea (PNG) is situated in the Pacific Ocean and has experienced multiple natural disasters and disease outbreaks. However, PNG lacks the ability to rapidly and systematically deploy trained personnel to provide surge capacity in response to major national disasters. It was therefore decided to establish a national emergency medical team (EMT) in PNG. PNG's responses to the 2018 earthquake in the Highlands Region and the coronavirus disease (COVID-19) pandemic required assistance from international EMTs. PNG began developing its own EMT in 2019, coinciding with the development of other Pacific EMTs. PNG's EMT project was initiated in 2019 with the creation of a technical working group. By 2021, a focal point had been identified, standard operating procedures had been drafted and training of EMT members had been completed. Pilot deployments of the national EMT members contributed to the COVID-19 response during 2021. Four major challenges were identified during the early phase of PNG's national EMT development: introducing the concept of EMTs in an EMT-naïve landscape; integrating the national EMT into existing PNG National Department of Health organizational structures; assembling adequate members at short notice to respond to disasters; and securing funding for deployment. Solutions identified for these challenges included strengthening stakeholder involvement through engagement in the development process and participation in technical working groups and consultative group discussions, offering exposure to other Pacific-based EMTs, and creating incentive schemes for EMT members and their place of employment.

РОЛЬ ЗЕМЛЕВЛАДЕЛЬЦЕВ В ОСВОЕНИИ ПРИРОДНЫХ РЕСУРСОВ ПАПУА – НОВОЙ ГВИНЕИ

The article analyzes the role of Papua New Guinea landowners in the distribution of profits from mining on the ancestral lands of clans (communities), their interaction with business in the implementation of major resource extraction projects, and provides an overview of the mineral resources sector of the Independent State of Papua New Guinea (PNG). Mining continues to drive the economic development of Papua New Guinea to this day. Large-scale extraction of natural resources in the country began after the country gained independence from Australia in 1975. The country with a population of about 10 million people, of whom about 87% live in rural areas, has largely preserved centuries-old traditions, as well as the right to land handed down to them by their ancestors. At the present stage, landowners and local communities are directly involved in the development of the country’s rich subsoil, having a certain share in resource projects, with the support of the government of Papua New Guinea, which is taking measures to legislate the rights of landowners to participate in resource extraction projects.

Prevalence of Salmonella and Campylobacter in Chicken among the Different Farming Systems in Papua New Guinea (PNG)

Prevalence of Salmonella and Campylobacter in Chicken among the Different Farming Systems in Papua New Guinea (PNG)

Leading causes of deaths in the mortality transition in Papua New Guinea: evidence from the Comprehensive Health and Epidemiological Surveillance System.

Changing causes of deaths in the mortality transition in Papua New Guinea (PNG) are poorly understood. This study analysed community-level data to identify leading causes of death in the population and variations across age groups and sexes, urban-rural sectors and provinces. Mortality surveillance data were collected from 2018-20 as part of the Comprehensive Health and Epidemiological Surveillance System (CHESS), using the World Health Organization 2016 verbal autopsy (VA) instrument. Data from 926 VA interviews were analysed, using the InterVA-5 cause of death analytical tool to assign specific causes of death among children (0-14 years), those of working age (15-64 years) and the elderly (65+ years). Nearly 50% of the total deaths were attributed to non-communicable diseases (NCDs), followed by infectious and parasitic diseases (35%), injuries and external causes (11%) and maternal and neonatal deaths (4%). Leading causes of death among children were acute respiratory tract infections (ARTIs) and diarrhoeal diseases, each contributing to 13% of total deaths. Among the working population, tuberculosis (TB) contributed to 12% of total deaths, followed by HIV/AIDS (11%). TB- and HIV/AIDS-attributed deaths were highest in the age group 25-34 years, at 20% and 18%, respectively. These diseases killed more females of working age (n = 79, 15%) than males (n = 52, 8%). Among the elderly, the leading causes of death were ARTIs (13%) followed by digestive neoplasms (10%) and acute cardiac diseases (9%). The variations in leading causes of death across the populations in PNG suggest diversity in mortality transition. This requires different strategies to address specific causes of death in particular populations.

Protecting Australian Protected Persons

This article examines the changing concepts of racialised citizenship in two intertwined nations: the Independent State of Papua New Guinea (‘PNG’) and the Commonwealth of Australia (‘Australia’), PNG’s former colonial ruler, as the latter sought to shake off the legacies of its recently abandoned ‘White Australia’ policy. It examines the historical intersection between PNG’s developing citizenship criteria, with its racialised articulation of who was ‘in’ and who was ‘out’, and Australia’s efforts to recast its image on the international stage as a multi-racial, non-racist and anti-imperial nation. Specifically, it demonstrates how the intersection of these policy choices impacted on a particular cohort of so-called ‘Australian Protected Persons’ (‘APPs’). APPs who happened also to fall outside PNG’s citizenship criteria were left stateless at PNG’s independence. Drawing on newly released Australian archival material, this article casts light on the particular historical moment that allowed for this outcome.

Genomic Sequencing of Dengue Virus Strains Associated with Papua New Guinean Outbreaks in 2016 Reveals Endemic Circulation of DENV-1 and DENV-2.

Over the past decade, the Pacific region has experienced many arboviral outbreaks, including dengue, chikungunya, and Zika viruses. Papua New Guinea (PNG) has a high burden of arboviral diseases, but there is a paucity of knowledge about the epidemiology and circulation of these viruses in the country. In this study, we report investigations into suspected arboviral outbreaks of febrile disease in PNG from December 2015 to June 2017. DENV-1 and DENV-2 were the mostly commonly detected viruses, and low circulation of DENV-3 and ZIKV was also detected. DENV-4 and CHIKV were not detected during this period. Full genome sequencing of selected positive samples revealed that circulation was dominated by endemic indigenous strains belonging to DENV-1 (genotype IV) and DENV-2 (genotype C) that have been present in the country for up to a decade. A DENV-2 sublineage was also identified that has been associated with outbreaks of severe dengue in both PNG and the Solomon Islands.

Predictors of unfavourable treatment outcome in patients diagnosed with drug-resistant tuberculosis in the Torres Strait / Papua New Guinea border region.

Drug-resistant tuberculosis (DR-TB) is an ongoing challenge in the Torres Strait Islands (TSI) / Papua New Guinea (PNG) border region. Treatment success rates have historically been poor for patients diagnosed with DR-TB, leading to increased transmission. This study aimed to identify variables associated with unfavourable outcome in patients diagnosed with DR-TB to inform programmatic improvements. A retrospective study of all DR-TB cases who presented to Australian health facilities in the Torres Strait between 1 March 2000 and 31 March 2020 was performed. This time period covers four distinct TB programmatic approaches which reflect Australian and Queensland Government decisions on TB management in this remote region. Univariate and multivariate predictors of unfavourable outcome were analysed. Unfavourable outcome was defined as lost to follow up, treatment failure and death. Successful outcome was defined as cure and treatment completion. In total, 133 patients with resistance to at least one TB drug were identified. The vast majority (123/133; 92%) of DR-TB patients had pulmonary involvement; and of these, 41% (50/123) had both pulmonary and extrapulmonary TB. Unfavourable outcomes were observed in 29% (39/133) of patients. Patients living with human immunodeficiency virus, renal disease or diabetes (4/133; 4/133; 3/133) had an increased frequency of unfavourable outcome (p <0.05), but the numbers were small. Among all 133 DR-TB patients, 41% had a low lymphocyte count, which was significantly associated with unfavourable outcome (p <0.05). We noted a 50% increase in successful outcomes achieved in the 2016-2020 programmatic period, compared to earlier periods (OR 5.3, 95% Confidence Interval [1.3, 20.4]). Being a close contact of a known TB case was associated with improved outcome. While DR-TB treatment outcomes have improved over time, enhanced surveillance for DR-TB, better cross border collaboration and consistent diagnosis and management of comorbidities and other risk factors should further improve patient care and outcomes.

Carl Schmitt and Chinese political thought: Relevance for Papua New Guinea and the Pacific

This article considers the relevance of the theories of German jurist Carl Schmitt for understanding Papua New Guinea (PNG) politics and international relations, with a focus on relations with China. In pursuing this analysis, the text gives particular emphasis to Schmitt’s friend–enemy distinction. In order to understand the regional context in which China has a growing presence, this article initially highlights the preoccupation of Chinese intellectuals with the ideas of Schmitt. It proceeds to mention the use of Schmitt’s ideas in supporting the particular ideological positions of Chinese liberals, the New Leftists, those who articulate the China Path and even the Chinese state. Through a comparative analysis I both compare how Schmittian ideas have been used by Chinese intellectuals to critique the economic inequality in Chinese society and alternatively the relevance of such critiques to the issues of social inequality in PNG. The discussion subsequently focuses on PNG’s international relations and China’s increasing economic and political influence. While the United States and its regional partner Australia appear to be alarmed by an expanding Chinese presence, others do not necessarily believe that Beijing has overreaching ambitions of global dominance. The article considers the suggestion that Chinese thinking on international relations has been influenced by Schmitt’s concept of the Großraum, an alternative to the Westphalian system, in which international relations are marked by a dominant hegemon and self-contained regional blocks consisting of constellated nations. As PNG finds itself in a critical position and subject to pressures from both the West and China, the text considers PNG sovereignty within a possible regional system in which China serves as the dominant hegemon.

Cigarette smoking during breastfeeding in Papua New Guinea: Prevalence and demographic and socio-economic predictors.

Cigarette smoking during breastfeeding is reported to contribute to significant changes in the composition of breast milk not only by reducing its protective features but also affecting infants' response to breastfeeding and breast milk. However, studies on the prevalence of cigarette smoking and associated factors during breastfeeding are limited in Papua New Guinea (PNG). This study estimates the prevalence of cigarette smoking and its association with demographic and economic factors among breastfeeding women in PNG. We used weighted survey data from the 2016-2018 PNG Demographic and Health Survey (PNGDHS). A weighted sample of 3,822 women who were breastfeeding during the survey were included in the study. The outcome variable in the present study is current cigarette smoking. A multiple logistic regression analysis was used to estimate the association between current cigarette smoking status and socio-demographic and economic variables of breastfeeding women. The regression analysis results were reported using adjusted odds ratios (aOR) with their respective 95% confidence intervals (CIs). From the weighted sample, the prevalence of cigarette smoking among breastfeeding women was 21.9%; of which 60.8% smoked daily. The mean number of cigarettes smoked in the last 24 hours preceding the survey was 6.05(SD = 5.99). Multiple logistic regression analysis revealed that breastfeeding women who were from the Momase (aOR: 2.337, CI: 1.786-3.058, p<0.001) and Highlands (AOR: 1.589, CI: 1.213-2.082, p = 0.001), had no religious affiliation (aOR: 3.665, CI: 1.235-10.877, p = 0.019), and households with daughters as household heads (aOR: 1.901, CI: 1.231-2.935, p = 0.004) and being in more than one union (aOR: 2.374, CI: 1.805-3.123, p<0.001) were significantly more likely to smoke cigarette compared to women from southern region, those affiliated to Anglican church, those with husband as household heads, and being in one union respectively. Cigarette smoking among breastfeeding women in PNG is relatively high, and region of residence, religion, relationship to household head, and the number of unions remain independent predictors. Interventions should target the individual socio-economic and cultural contexts within which breastfeeding occurs.

Currents off the Papua New Guinea Coast During and After the El Niño of 2015–2016

AbstractInterannual variation of New Guinea Coastal Undercurrent (NGCUC) along the Papua New Guinea (PNG) coast was investigated using mooring observations during 2015–2019 combined with eddy‐resolving simulations of the Ocean General Circulation Model for the Earth Simulator (OFES) during 1980–2019. Strong interannual variation appears in the upper 800 m of the currents recorded by the mooring, which is well reproduced by OFES outputs. On the interannual time scale, a relatively larger proportion (1.1 Sv) of the transport signals related to El Niño/Southern Oscillation (ENSO) in the Solomon Sea is transmitted through the Solomon Strait, while about 0.84 Sv of ENSO signal is through the Vitiaz Strait due to the topography constraint. As the NGCUC flows along the PNG coast, the mean transport above 400 m gradually increases while its relationship with ENSO rapidly weakens. This weakening is due to its merging with the westward South Equatorial Current (SEC). The westward SEC weakens (strengthens) during El Niño (La Niña) events, which weakens the interannual signal of NGCUC. The interannual variations of the currents above and below the thermocline off the PNG coast are opposite: a clockwise anomalous circulation straddling the equator appears above the thermocline, while a counterclockwise anomalous circulation appears below the thermocline during El Niño, which is connected to the recharge‐discharge oscillation during ENSO cycle.

The relationship between fathers' heavy episodic drinking and fathering involvement in five Asia-Pacific countries: Anindividual participant data meta-analysis.

This study aims to increase understanding of the relationship between heavy episodic drinking (HED) and fathers' involvement in parenting in five countries. The potential moderating effect of fathers' experiences of childhood trauma is also studied, controlling for the possible confounding of the effect of HED by father's attitudes toward gender equality, father's age and father's education. United Nations Multi-Country Study on Men and Violence (UNMCS) survey data from 4562 fathers aged 18-49 years from Cambodia, China, Indonesia and Papua New Guinea (PNG) and Sri Lanka were used to assess the relationship between fathering involvement (e.g., helping children with their homework) and self-reported HED of 6+ drinks in one occasion vs. non-HED and abstaining. Moderating effects of a 13-item fathers' childhood trauma (FCT) scale were tested and analyses were adjusted for gender-inequitable attitudes using the Gender-Equitable Men scale score. Bivariate and adjusted individual participant meta-analyses were used to determine effect estimates for each site and across all sites. Fathers' HED was associated with less positive parental involvement after adjusting for gender-equitable attitudes, FCT, age and education. No overall interaction between HED and FCT was identified. Gender equitable attitudes were associated with fathering involvement in some countries but not overall (p=0.07). Heavy episodic drinking was associated with reduced positive fathering involvement. These findings suggest that interventions to increase fathers' involvement in parenting should include targeting reductions in fathers' HED. Structural barriers to fathers' involvement should be considered alongside HED in future studies of fathers' engagement with their children.

Coating formulation change leads to inferior performance of long-lasting insecticidal nets in Papua New Guinea

BackgroundLong-lasting insecticidal nets (LLINs) play a key role in reducing malaria transmission in endemic countries. In a previous study, the authors demonstrated a substantial decrease in the bioefficacy of LLINs for malaria prevention delivered to Papua New Guinea (PNG) between 2013 and 2019. This coincided with a rise in malaria cases in the country. The present study was aimed at determining the underlying cause of the reduced bioefficacy observed in these LLINs. The main hypothesis was that a change in the coating formulation of the respective LLIN product was responsible, and had led to significantly altered product properties and performance.MethodsA set of PermaNet® 2.0 LLIN samples (n = 12) manufactured between 2007 and 2019 was subjected to combustion ion chromatography in order to understand the chemistry of the LLIN polymer coating formulation. In addition, World Health Organization (WHO) LLIN standard wash tests and cone bioassays were conducted to further characterize the change in product performance that occurred between 2012 and 2013.ResultsHigh polymer fluorine content (average 3.2 g/kg) was measured in PermaNet® 2.0 manufactured up to 2012, whereas nets which were manufactured after 2012 contained very little polymer fluorine (average 0.04 g/kg) indicating a coating formulation change from a fluorocarbon (FC)-based to a non-FC-based formulation. The coating formulation change as part of the manufacturing process thus resulted in a significant reduction in bioefficacy. In addition, the manufacturing change affected wash resistance leading to a faster reduction in 24 h mosquito mortality in the non-FC-coated product with consecutive washes.ConclusionA change in coating formulation of PermaNet® 2.0 resulted in reduced product performance in PNG. Post-2012 PermaNet® 2.0 LLINs should not be considered to be the same product as PermaNet® 2.0 LLINs produced prior to and in 2012. Coating formulation changes should be validated to not impact LLIN product performance.

Stratification of malaria incidence in Papua New Guinea (2011-2019): Contribution towards a sub-national control policy.

Malaria risk in Papua New Guinea (PNG) is highly heterogeneous, between and within geographical regions, which is operationally challenging for control. To enhance targeting of malaria interventions in PNG, we investigated risk factors and stratified malaria incidence at the level of health facility catchment areas. Catchment areas and populations of 808 health facilities were delineated using a travel-time accessibility approach and linked to reported malaria cases (2011-2019). Zonal statistics tools were used to calculate average altitude and air temperature in catchment areas before they were spatially joined with incidence rates. In addition, empirical Bayesian kriging (EBK) was employed to interpolate incidence risk strata across PNG. Malaria annual incidence rates are, on average, 186.3 per 1000 population in catchment areas up to 600 m, dropped to 98.8 at (800-1400) m, and to 24.1 cases above 1400 m altitude. In areas above the two altitudinal thresholds 600m and 1400m, the average annual temperature drops below 22°C and 17°C, respectively. EBK models show very low- to low-risk strata (<100 cases per 1000) in the Highlands, National Capital District and Bougainville. In contrast, patches of high-risk (>200 per 1000) strata are modelled mainly in Momase and Islands Regions. Besides, strata with moderate risk (100-200) predominate throughout the coastal areas. While 35.7% of the PNG population (estimated 3.33 million in 2019) lives in places at high or moderate risk of malaria, 52.2% (estimated 4.88 million) resides in very low-risk areas. In five provinces, relatively large proportions of populations (> 50%) inhabit high-risk areas: New Ireland, East and West New Britain, Sandaun and Milne Bay. Incidence maps show a contrast in malaria risk between coastal and inland areas influenced by altitude. However, the risk is highly variable in low-lying areas. Malaria interventions should be guided by sub-national risk levels in PNG.

Insecticide resistance in malaria and arbovirus vectors in Papua New Guinea, 2017–2022

BackgroundInsecticide resistance (IR) monitoring is essential for evidence-based control of mosquito-borne diseases. While widespread pyrethroid resistance in Anopheles and Aedes species has been described in many countries, data for Papua New Guinea (PNG) are limited. Available data indicate that the local Anopheles populations in PNG remain pyrethroid-susceptible, making regular IR monitoring even more important. In addition, Aedes aegypti pyrethroid resistance has been described in PNG. Here, Anopheles and Aedes IR monitoring data generated from across PNG between 2017 and 2022 are presented.MethodsMosquito larvae were collected in larval habitat surveys and through ovitraps. Mosquitoes were reared to adults and tested using standard WHO susceptibility bioassays. DNA from a subset of Aedes mosquitoes was sequenced to analyse the voltage-sensitive sodium channel (Vssc) region for any resistance-related mutations.ResultsApproximately 20,000 adult female mosquitoes from nine PNG provinces were tested. Anopheles punctulatus sensu lato mosquitoes were susceptible to pyrethroids but there were signs of reduced mortality in some areas. Some Anopheles populations were also resistant to DDT. Tests also showed that Aedes. aegypti in PNG are resistant to pyrethroids and DDT and that there was also likelihood of bendiocarb resistance. A range of Vssc resistance mutations were identified. Aedesalbopictus were DDT resistant and were likely developing pyrethroid resistance, given a low frequency of Vssc mutations was observed.ConclusionsAedes aegypti is highly pyrethroid resistant and also shows signs of resistance against carbamates in PNG. Anopheles punctulatus s.l. and Ae. albopictus populations exhibit low levels of resistance against pyrethroids and DDT in some areas. Pyrethroid-only bed nets are currently the only programmatic vector control tool used in PNG. It is important to continue to monitor IR in PNG and develop proactive insecticide resistance management strategies in primary disease vectors to retain pyrethroid susceptibility especially in the malaria vectors for as long as possible.Graphic abstract