Pulsed-field gel electrophoresis (PFGE) of XbaI-digested chromosomal DNA was performed on 133 strains of Salmonella enterica serovar Typhi obtained from Papua New Guinea, with the objective of assessing the temporal variation of these strains. Fifty-two strains that were isolated in 1992 and 1994 were of one phage type, D2, and only two predominant PFGE profiles, X1 and X2, were present. Another 81 strains isolated between 1997 and 1999 have shown divergence, with four new phage types, UVS I (n = 63), UVS (n = 5), VNS (n = 4), and D1 (n = 9), and more genetic variability as evidenced by the multiple and new PFGE XbaI profiles (21 profiles; Dice coefficient, F = 0.71 to 0.97). The two profiles X1 and X2 have remained the stable, dominant subtypes since 1992. Cluster analysis based on the unweighted pair group method using arithmetic averages algorithm identifies two main clusters (at 87% similarity), indicating that the divergence of the PFGE subtypes was probably derived from some genomic mutations of the X1 and X2 subtypes. The majority of isolates were from patients with mild and moderate typhoid fever and had various XbaI profiles. A single isolate from a patient with fatal typhoid fever had a unique X11 profile, while four of six isolates from patients with severe typhoid fever had the X1 pattern. In addition, 12 paired serovar Typhi isolates recovered from the blood and fecal swabs of individual patients exhibited similar PFGE patterns, while in another 11 individuals paired isolates exhibited different PFGE patterns. Three pairs of isolates recovered from three individuals had different phage types and PFGE patterns, indicating infection with multiple strains. The study reiterates the usefulness of PFGE in assessing the genetic diversity of S. enterica serovar Typhi for both long-term epidemiology and in vivo stability and instability within an individual patient.
Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) mediates parasite sequestration to the cerebral microvasculature via binding of DBLβ domains to intercellular adhesion molecule 1 (ICAM1) and is associated with severe cerebral malaria. In a cohort of 187 young children from Papua New Guinea (PNG), we examined baseline levels of antibody to the ICAM1-binding PfEMP1 domain, DBLβ3PF11_0521, in comparison to four control antigens, including NTS-DBLα and CIDR1 domains from another group A variant and a group B/C variant. Antibody levels for the group A antigens were strongly associated with age and exposure. Antibody responses to DBLβ3PF11_0521 were associated with a 37% reduced risk of high-density clinical malaria in the follow-up period (adjusted incidence risk ratio [aIRR] = 0.63 [95% confidence interval {CI}, 0.45 to 0.88; P = 0.007]) and a 25% reduction in risk of low-density clinical malaria (aIRR = 0.75 [95% CI, 0.55 to 1.01; P = 0.06]), while there was no such association for other variants. Children who experienced severe malaria also had significantly lower levels of antibody to DBLβ3PF11_0521 and the other group A domains than those that experienced nonsevere malaria. Furthermore, a subset of PNG DBLβ sequences had ICAM1-binding motifs, formed a distinct phylogenetic cluster, and were similar to sequences from other areas of endemicity. PfEMP1 variants associated with these DBLβ domains were enriched for DC4 and DC13 head structures implicated in endothelial protein C receptor (EPCR) binding and severe malaria, suggesting conservation of dual binding specificities. These results provide further support for the development of specific classes of PfEMP1 as vaccine candidates and as biomarkers for protective immunity against clinical P. falciparum malaria.
Distal renal tubular acidosis (dRTA) caused by mutations of the SLC4A1 gene encoding the erythroid and kidney isoforms of anion exchanger 1 (AE1 or band 3) has a high prevalence in some tropical countries, particularly Thailand, Malaysia, the Philippines and Papua New Guinea (PNG). Here the disease is almost invariably recessive and can result from either homozygous or compound heterozygous SLC4A1 mutations.
Nipah virus is a recently emergent paramyxovirus that is capable of causing severe disease in both humans and animals. The first outbreak of Nipah virus occurred in Malaysia and Singapore in 1999 and, more recently, outbreaks were detected in Bangladesh. In humans, Nipah virus causes febrile encephalitis with respiratory syndrome that has a high mortality rate. The reservoir for Nipah virus is believed to be fruit bats, and humans are infected by contact with infected bats or by contact with an intermediate animal host such as pigs. Person to person spread of the virus has also been described. Nipah virus retains many of the genetic and biologic properties found in other paramyxoviruses, though it also has several unique characteristics. However, the virologic characteristics that allow the virus to cause severe disease over a broad host range, and the epidemiologic, environmental and virologic features that favor transmission to humans are unknown. This review summarizes what is known about the virology, epidemiology, pathology, diagnosis and control of this novel pathogen.
BACKGROUND: There is a surgical workforce shortage in Papua New Guinea (PNG), the Pacific and Timor Leste. Previously, Pacific Island specialists who trained overseas tended to migrate.
METHODS: A narrative review was undertaken of the training programmes delivered through the University of Papua New Guinea and Fiji National University's Fiji School of Medicine, and support provided through Australian Aid and the Royal Australasian College of Surgeons (RACS), including scholarships and visiting medical teams.
RESULTS: The Fiji School of Medicine MMed programme, which commenced in 1998, has 39 surgical graduates. Sixteen of 22 Fijians, nine of ten Solomon Islanders and four of five in Vanuatu currently reside and/or work in-country. Surgical training in PNG began in 1975, and now has 104 general surgical graduates, 11 of whom originate from the Pacific Islands or Timor Leste. The PNG retention rate of local graduates is 97 per cent, with 80 per cent working in the public sector. Twenty-two surgeons have also undertaken subspecialty training. Timor Leste has trained eight surgical specialists in PNG, Fiji, Indonesia or Malaysia. All have returned to work in-country. The RACS has managed Australian Aid programmes, providing pro bono visiting medical teams to support service delivery and, increasingly, capacity building in the region. The RACS has funded scholarships and international travel grants to further train or sustain the surgical specialists.
CONCLUSION: The local MMed programmes have been highly successful in retaining specialists in the region. Partnerships with Australian Aid and RACS have been effective in ensuring localization of the faculty and ongoing professional development.
Public concern about the adverse environmental and human health impacts of organochlorine contaminants led to strict regulations on their use in developed nations two decades ago. Nevertheless, DDT and several other organochlorine insecticides are still being used for agriculture and public health programs in developing countries in Asia and the South Pacific. As a consequence, humans in this region are exposed to greater dietary levels of organochlorines. In this review, published information on organochlorine concentrations in foodstuffs from South and Southeast Asia and Oceanic countries has been compiled. Foodstuffs that contribute to human exposures and dietary intakes of organochlorines were examined, and the data compared with those reported from more developed nations. Among various developing countries in Asia, considerable information on organochlorines in foodstuffs has been available from India since the late 1960s. DDT and HCH were the major insecticides in Indian foodstuffs. Concentrations of these insecticides have declined more than two orders of magnitude in farm products, such as food grains and vegetables, in two decades. Milk and milk products are the major sources of dietary exposure to DDT and HCH in India. The residues of these insecticides in dairy products were close to or above the MRLs of the FAO/WHO. Dietary intake of DDT and HCH by Indians was > 100 fold that in more developed nations. Sporadic incidences of greater concentrations (> 1 microgram/g) of aldrin, dieldrin, and heptachlor have been measured in Indian vegetables. Untreated surface waters could be a potential source of DDT and HCH exposure. In most Southeast Asian countries DDT was the common contaminant in animal origin foodstuffs. The higher percentage of p,p'-DDT in meat and fish from Southeast Asian countries, except Japan and Korea, indicated the recent use of DDt in vector control operations. Dietary intakes of DDt and HCH in Southeast Asia were an order of magnitude less than those of Indians but 5- to 10 fold greater than in more developed nations. In addition to DDT, aldrin and dieldrin were prominent in meat collected from Thailand and Malaysia. Aquatic food products from more industrialized countries, such as Japan, South Korea, Hong Kong, and Taiwan, contained significant levels of PCBs. In South Pacific countries, particularly in Australia and New Zealand, chlordanes and PCBs were the most prevalent organochlorines in foodstuffs. Food contamination by DDT, HCH, aldrin, and dieldrin was less than in developing countries in Asia but greater than in the U.S. and Japan. Intake of PCBs in Australia was greater than in the U.S. Meat and fish were the major sources of organochlorine exposure by Australians. Human dietary intake of organochlorines has been declining more slowly in developing countries in Asia. Current intakes were at least 5- to 100 fold greater than those in more developed nations, suggesting a greater risk from organochlorine exposure. Factors such as malnutrition, common among rural poor in developing nations, can increase these risks. Of greatest concern is the magnitude of exposure to organochlorines to which infants and children are subjected through human and dairy milk. The estimated intake of DDT by infants was at least 100 fold greater than the ADI of the FAO/WHO. In addition to DDT, excessive exposures to HCH and dieldrin may cause potential health effects in infants because they are more vulnerable to toxic effects. The design and implementation of appropriate epidemiological studies and their integration with monitoring of human, food, and environmental samples would be a major step in assessing the risks of organochlorine residues in foods and controlling or eliminating them. With the continued globalization of trade in food products, and the concomitant risk that food contaminated through point-source pollution may be widely distributed, identification of sources and their control should be matters of
Chloroquine-resistant Plasmodium vivax was originally reported in Papua, New Guinea by Reickman in 1989.1 In the same year, in Colombia, South America, Arias and Corredor2 reported relapses of 11 patients suffering from vivax malaria, following a chloroquine-primaquine regimen. Garavelli and Corti3 suggested chloroquine-resistant Plasmodium vivax may be present in Brazil following these therapeutic relapses. Further therapeutic failures in returned travelers from South America were reported by Moore et al (1994).4 We report vivax malaria in a group of expeditioners visiting Guyana who, whereas compliant with antimalarial chemoprophylaxis, developed clinical malaria, adding evidence to the presence of chloroquine-resistant Plasmodium vivax in South America. Raleigh International is a youth development charity that undertakes environmental and community projects around the world. These are usually in remote locations. Nine expeditions in countries such as Chile, Belize, Zimbabwe, Uganda, and Malaysia are organized annually. A project manager and a medical officer are placed at each site, along with approximately 10 venturers (age 17-25.) Participants are of all nationalities, but, at present, they are predominantly British.
One new species and two new subspecies of fleas are described. These are S. sulawesiensis n. sp. from North and Central Sulawesi, S. alticola pilosus n. ssp. from Central Sulawesi, and S. alticola crassinavis n. ssp. from North Sulawesi. All three of these new taxa are ectoparasites of native, endemic murine rodents. Two of the new taxa, S. sulawesiensis and S. alticola crassinavis, coexist on the same mountain, Gunung Moajat, in North Sulawesi. The related S. alticola alticola, which becomes the nominate subspecies, parasitises the murine rodent Maxomys alticola in northern Borneo (Sabah) and it is hypothesized that Sigmactenus first colonized Sulawesi as an ectoparasite of ancestral Maxomys, or perhaps Rattus, as these murines dispersed from southeast Asia to Sulawesi; 15 endemic murine rodent species belonging to these two genera are known to currently inhabit Sulawesi. An identification key and distribution map are included for all known species and subspecies of Sigmactenus. In addition to the three new taxa and S. a. alticola, these include: S. celebensis from South Sulawesi, S. timorensis from Timor, S. toxopeusi from New Guinea, and S. werneri from the Philippines (Mindanao and Negros).
Persistent organochlorines in air, river water and sediment samples were analysed from eastern and southern Asia (India, Thailand, Vietnam, Malaysia, Indonesia) and Oceania (Papua New Guinea and Solomon Islands) to elucidate their geographical distribution in tropical environment. The concentrations of organochlorines in these abiotic samples collected from Taiwan, Japan and Australia were also monitored for comparison. Atmospheric and hydrospheric concentrations of HCHs (hexachlorocyclohexanes) and DDTs (DDT and its metabolites) in the tropical developing countries were apparently higher than those observed in the developed nations, suggesting extensive usage of these chemicals in the lower latitudes. CHLs (chlordane compounds) and PCBs (polychlorinated biphenyls) were also occasionally observed at higher levels in the tropics, implying that their usage area is also expanding southward. Distribution patterns of organochlorines in sediments showed smaller spatial variations on global terms, indicating that the chemicals released in the tropical environment are dispersed rapidly through air and water and retained less in sediments. The ratios of organochlorine concentrations in sediment and water phases were positively correlated with the latitude of sampling, suggesting that persistent and semivolatile compounds discharged in the tropics tend to be redistributed on a global scale.
Ovalocytosis, an hereditary condition in which most erythrocytes are oval in shape, is a polymorphism that occurs in up to 20% or more of the population in Papua New Guinea and Malaysia. Due to the geographical correlation of the trait with endemic malaria, the possibility of a selective advantage in resistance to malaria has been raised. In a study of 202 individuals with greater than or equal to 50% oval red cells matched by age, sex and village of residence with controls having less than or equal to 30% oval cells, ovalocytic subjects had blood films negative for Plasmodium vivax (P = 0.009), for P. falciparum (P = 0.044), and for all species of malaria parasites (P = 0.013), more often than controls. Among individuals parasitaemic at any time there were no clear differences in density of parasitaemia. However, in children 2 to 4 years old, parasite densities of both species were lower in ovalocytic subjects than in controls (0.01 less than P less than 0.025). The differential susceptibility to malaria infection suggested by this study has implications for the evaluation of interventions, including possible future vaccine field trials, in populations where high-frequency ovalocytosis is present.
Needle-fish are slender silvery fish with long pointed beaks. They are commonly seen swimming beneath the surface near fringing reefs in the Indo-Pacific area. Such areas are also frequented by Melanesian villagers. The speed of needle-fish, together with their tendency to leap out of the water when bright lights are used for fishing and at other times, occasionally result in deep, penetrating injuries to swimmers, waders, and, in particular, to fishermen who are working at night from small canoes. Injuries from needle-fish are a relatively common occupational hazard of subsistence village life in Oceania, and probably also for some fishermen in other coastal environments, such as those in Japan and Malaysia.
A hypothesis suggested in this paper is that pigbel, or enteritis necroticans was a common disease in mediaeval Europe when human habitats, food hygiene, protein deficiency and periodic meat feasting formed the basics of village life as they do in many Third World cultures today. Based on the Papua New Guinea experience with pigbel, it is suggested that health authorities should look closely at the epidemiology of the acute surgical abdomen in such communities. Enteritis necroticans may be the important predisposing lesion to mid-gut volvulus, jejunal and ileal ileus and other forms of small bowel strangulation in communities where protein deprivation, poor food hygiene, epochal meat feasting and staple diets containing trypsin inhibitors co-exist. Such human habitats occur in Central South America, Western Pacific, Asian and South-East Asian cultures. Isolated outbreaks of necrotising enteritis have been reported from Uganda, Malaysia and Indonesia but as yet no systematic epidemiological studies of the prevalence of small bowel strangulations have been described in the surgical literature of Third World countries. Now that enteritis necroticans is preventable by vaccination such studies should be undertaken.
The complete mitochondrial genome of a highland freshwater crayfish, Cherax monticola, was recovered by shotgun sequencing. The mitogenome consists of 15,917 base pairs containing 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs and a non-coding AT-rich region. The base composition of C. monticola is 33.46% for T, 21.48% for C, 33.71% for A and 11.35% for G, with an AT bias of 67.17%.
The small pseudoscorpion family Pseudochiridiidae Chamberlin, 1923 comprises two genera and 12 extant species recorded from Asia (Burma, Christmas Island, Indonesia, India, Nepal, Malaysia, New Guinea, Philippines, Nicobars and Sumba), eastern, central and southern Africa (Chad, D.R. Congo, Kenya, South Africa, Tanzania), Madagascar, Seychelles (Aldabra), North America (Florida) and the Caribbean Islands of Dominican Republic and Cuba (Harvey 2013, Barba & Barroso 2013); one unidentified species is mentioned for the fauna of Mexico (Ceballos 2004). A fossil species has been described from Dominican amber by Judson (2007), who predicted the presence of this family in South America.
The Oriental, Australasian and Oceanian genus Caiusa Surcouf, 1920 is revised, species concepts being based on male and female genitalia. A key to males for all known species, and a key to females for all except one are given. All relevant types still in existence have been studied, complete synonymies given and the geographical distribution reconsidered. The eight species included in the genus are: Caiusa borneoensis sp. nov. (Malaysia, Thailand, Vietnam); Caiusa coomani Séguy, 1948 (China, Malaysia, Singapore, Thailand, Vietnam); Caiusa indica Surcouf, 1920 (Australia, Cambodia, India, Indonesia, Malaysia, Papua New Guinea, Philippines, Singapore, Solomon Islands, Sri Lanka, Thailand, Vietnam); Caiusa karrakerae sp. nov. (Malaysia, Thailand); Caiusa kurahashii sp. nov. (Indonesia, Japan, Philippines); Caiusa pooae sp. nov. (Thailand); Caiusa testacea Senior-White, 1923 (India, Nepal, Sri Lanka) and Caiusa violacea Séguy, 1925, stat. rev. (Cambodia, China, Laos, Malaysia, Taiwan, Thailand, Vietnam). A lectotype is designated for Caiusa indica to fix the interpretation of the name. Caiusa nigronitens Senior-White, 1923, syn. nov. and Caiusa surcoufi Bezzi, 1927, syn. nov. are established as junior synonyms of Caiusa indica. Caiusa violacea is correctly diagnosed and errors in the original description of the female holotype are pointed out. Caiusa dubiosa Villeneuve, 1927 is established as a junior synonym of C. violacea, syn. nov. Seven Caiusa species have been reared from the egg mass of various species of frogs. The reproductive mode of the eighth species, i.e., C. indica, is unknown. Five species, i.e., C. borneoensis, C. coomani, C. karrakerae, C. kurahashii and C. violacea have been reared from one or more of the foam nesting frog species Chiromantis nongkhorensis (Cochran, 1927), Polypedates leucomystax (Gravenhorst, 1927), Polypedates megacephalus Hallowell, 1861, Rhacophorus annamensis Smith, 1924, Rhacophorus dulitensis Boulenger, 1892, Rhacophorus kio Ohler & Delorme, 2005 and Rhacophorus owstoni (Stejneger, 1907) all belonging in the family Rhacophoridae in Anura. These five Caiusa species all have a specialised ovipositor tip, with small spine-like setae on the ST8 and the hypoproct, probably enabling the flies to oviposit on a foam nest with a hardened outer surface. They form a monophyletic group on account of these features of the ovipositor, unique in the Oestroidea. The sixth species, C. testacea, has been reared from a frog egg mass, the frog species being unknown. Its ovipositor structure is also unknown. The seventh species, C. pooae, has been reared once from the jelly-like egg mass of Feihyla hansenae (Cochran, 1927), also in Rhacophoridae. Caiusa pooae females do not have spine-like setae on the ovipositor, a fact correlated with the soft outer surface of the jelly-like egg mass on which a C. pooae female had oviposited. The extreme rarity of C. pooae oviposition on Feihyla hansenae egg masses may indicate that this fly perhaps has another, unknown, regular oviposition substrate. Caiusa pooae and C. indica make up a second monophyletic group within Caiusa. Caiusa indica, the most common and most widespread species of the genus, has an ovipositor structure similar to C. pooae. Its breeding substrate is unknown and it occurs both within and outside the distributional area of Rhacophoridae. Possibly both C. indica and C. pooae share a regular oviposition substrate that has still to be discovered. The holotype female of Plinthomyia emimelania Rondani, 1875 from Sarawak is established as a member of the genus Bengalia Robineau-Desvoidy, 1830, thus Plinthomyia Rondani, 1875 becomes a junior synonym of Bengalia Robineau-Desvoidy, 1830, syn. nov. It is removed from the synonymy of Phumosia Robineau-Desvoidy, 1830.
New taxonomic and faunistic data for nine species of Paraphloeostiba Steel, 1960 and one species of Xanthonomus Bernhauer, 1926 (X. guineensis Shavrin, 2024) from the eastern Palaearctic, Oriental and Papuan regions are provided. Three new species of Paraphloeostiba are described and illustrated: P. acrolochaoides sp. nov. and P. brevicula sp. nov. from Papua New Guinea, and P. zingiberiphila sp. nov. from Malaysia (Sabah). Four species are recorded for the first time: P. gayndanensis (MacLeay, 1873) from Guangxi Province of China, Laos and Japan (Amami-Ōshima), P. papuana (Cameron, 1931) and P. riedeli Shavrin, 2024 from Papua New Guinea, and P. steeli Shavrin, 2024 from Indonesia (Sulawesi).
New Guinea is the world's largest tropical island and has fascinated naturalists for centuries1,2. Home to some of the best-preserved ecosystems on the planet3 and to intact ecological gradients-from mangroves to tropical alpine grasslands-that are unmatched in the Asia-Pacific region4,5, it is a globally recognized centre of biological and cultural diversity6,7. So far, however, there has been no attempt to critically catalogue the entire vascular plant diversity of New Guinea. Here we present the first, to our knowledge, expert-verified checklist of the vascular plants of mainland New Guinea and surrounding islands. Our publicly available checklist includes 13,634 species (68% endemic), 1,742 genera and 264 families-suggesting that New Guinea is the most floristically diverse island in the world. Expert knowledge is essential for building checklists in the digital era: reliance on online taxonomic resources alone would have inflated species counts by 22%. Species discovery shows no sign of levelling off, and we discuss steps to accelerate botanical research in the 'Last Unknown'8.