Prehistoric birds from New Ireland, Papua New Guinea: extinctions on a large Melanesian island.
At least 50 species of birds are represented in 241 bird bones from five late Pleistocene and Holocene archaeological sites on New Ireland (Bismarck Archipelago, Papua New Guinea). The bones include only two of seabirds and none of migrant shorebirds or introduced species. Of the 50 species, at least 12 (petrel, hawk, megapode, quail, four rails, cockatoo, two owls, and crow) are not part of the current avifauna and have not been recorded previously from New Ireland. Larger samples of bones undoubtedly would indicate more extirpated species and refine the chronology of extinction. Humans have lived on New Ireland for ca. 35,000 years, whereas most of the identified bones are 15,000 to 6,000 years old. It is suspected that most or all of New Ireland's avian extinction was anthropogenic, but this suspicion remains undetermined. Our data show that significant prehistoric losses of birds, which are well documented on Pacific islands more remote than New Ireland, occurred also on large, high, mostly forested islands close to New Guinea. (+info)
Ability to pay for health care: concepts and evidence.
In many developing countries people are expected to contribute to the cost of health care from their own pockets. As a result, people's ability to pay (ATP) for health care, or the affordability of health care, has become a critical policy issue in developing countries, and a particularly urgent issue where households face combined user fee burdens from various essential service sectors such as health, education and water. Research and policy debates have focused on willingness to pay (WTP) for essential services, and have tended to assume that WTP is synonymous with ATP. This paper questions this assumption, and suggests that WTP may not reflect ATP. Households may persist in paying for care, but to mobilize resources they may sacrifice other basic needs such as food and education, with serious consequences for the household or individuals within it. The opportunity costs of payment make the payment 'unaffordable' because other basic needs are sacrificed. An approach to ATP founded on basic needs and the opportunity costs of payment strategies (including non-utilization) is therefore proposed. From the few studies available, common household responses to payment difficulties are identified, ranging from borrowing to more serious 'distress sales' of productive assets (e.g. land), delays to treatment and, ultimately, abandonment of treatment. Although these strategies may have a devastating impact on livelihoods and health, few studies have investigated them in any detail. In-depth longitudinal household studies are proposed to develop understanding of ATP and to inform policy initiative which might contribute to more affordable health care. (+info)
To contract or not to contract? Issues for low and middle income countries.
Many low and middle income countries have inherited publicly funded and provided health services, often operating at relatively low levels of technical efficiency. Changing ideas about the management of the public sector, in particular stemming from new public management theory, are spreading to these countries, whether directly or via the recommendations of multilateral and bilateral aid agencies. Pronouncements of agencies such as the World Bank imply that competitive contracting with the private sector is likely to improve the efficiency of services provision. However, very little evidence is available on whether this is likely to be the case, and in what circumstances delivery of services through contracts with the private sector is likely to be preferable to direct provision by the public sector. This paper draws on evidence from five country case-studies of contractual arrangements, in Bombay, Papua New Guinea, South Africa, Thailand and Zimbabwe, done through collaborative research between the LSHTM Health Economics and Financing Programme and local researchers in each country. A common evaluative framework was applied in each country to selected, existing contractual arrangements. Services provided under contract and evaluated included catering, cleaning, security, diagnostic services and whole hospitals. Information is presented on the design of contracts, the process of agreeing contracts including the extent of competition, and the monitoring of contract performance. A variety of evidence, including information on the relative cost and quality of contracted out versus directly provided services in the case of South Africa, Thailand, and Bombay, is used to explore whether or not contracting out to the private sector represented a preferable means of service provision. This analysis, together with information on the capacity of the agency letting the contract, and on the wider environment including the level of development of the private sector, is used to identify which aspects of the contracting process and the context in which it takes place are important in influencing whether or not contracting with the private sector is a desirable means of service provision. (+info)
Protection of breastfeeding in Papua New Guinea.
In Papua New Guinea the bottle-feeding of babies has been increasing, predominantly among unemployed women of low educational status. Many women are unaware of their legal right to have breaks at work for the purpose of breastfeeding, and a high proportion of workplaces have no facilities for mothers who wish to breastfeed their children. The laws on the feeding of infants should be updated and implemented, and an effort is needed to explain the benefits of breastfeeding and the rights of working mothers. (+info)
Aggregation and distribution of strains in microparasites.
Recent research has shown that many parasite populations are made up of a number of epidemiologically distinct strains or genotypes. The implications of strain structure or genetic diversity for parasite population dynamics are still uncertain, partly because there is no coherent framework for the interpretation of field data. Here, we present an analysis of four published data sets for vector-borne microparasite infections where strains or genotypes have been distinguished: serotypes of African horse sickness (AHS) in zebra; types of Nannomonas trypanosomes in tsetse flies; parasite-induced erythrocyte surface antigen (PIESA) based isolates of Plasmodium falciparum malaria in humans, and the merozoite surface protein 2 gene (MSP-2) alleles of P. falciparum in humans and in anopheline mosquitoes. For each data set we consider the distribution of strains or types among hosts and any pairwise associations between strains or types. Where host age data are available we also compare age-prevalence relationships and estimates of the force of infection. Multiple infections of hosts are common and for most data sets infections have an aggregated distribution among hosts with a tendency towards positive associations between certain strains or types. These patterns could result from interactions (facilitation) between strains or types, or they could reflect patterns of contact between hosts and vectors. We use a mathematical model to illustrate the impact of host-vector contact patterns, finding that even if contact is random there may still be significant aggregation in parasite distributions. This effect is enhanced if there is non-random contact or other heterogeneities between hosts, vectors or parasites. In practice, different strains or types also have different forces of infection. We anticipate that aggregated distributions and positive associations between microparasite strains or types will be extremely common. (+info)
Prevention of cerebral malaria in children in Papua New Guinea by southeast Asian ovalocytosis band 3.
Southeast Asian ovalocytosis (SAO) occurs at high frequency in malarious regions of the western Pacific and may afford a survival advantage against malaria. It is caused by a deletion of the erythrocyte membrane band 3 gene and the band 3 protein mediates the cytoadherence of parasitized erythrocytes in vitro. The SAO band 3 variant may prevent cerebral malaria but it exacerbates malaria anemia and may also increase acidosis, a major determinant of mortality in malaria. We undertook a case-control study of children admitted to hospital in a malarious region of Papua New Guinea. The SAO band 3, detected by the polymerase chain reaction, was present in 0 of 68 children with cerebral malaria compared with six (8.8%) of 68 matched community controls (odds ratio = 0, 95% confidence interval = 0-0.85). Median hemoglobin levels were 1.2 g/dl lower in malaria cases with SAO than in controls (P = 0.035) but acidosis was not affected. The remarkable protection that SAO band 3 affords against cerebral malaria may offer a valuable approach to a better understanding of the mechanisms of adherence of parasitized erythrocytes to vascular endothelium, and thus of the pathogenesis of cerebral malaria. (+info)
Peopling of Sahul: mtDNA variation in aboriginal Australian and Papua New Guinean populations.
We examined genetic affinities of Aboriginal Australian and New Guinean populations by using nucleotide variation in the two hypervariable segments of the mtDNA control region (CR). A total of 318 individuals from highland Papua New Guinea (PNG), coastal PNG, and Aboriginal Australian populations were typed with a panel of 29 sequence-specific oligonucleotide (SSO) probes. The SSO-probe panel included five new probes that were used to type an additional 1,037 individuals from several Asian populations. The SSO-type data guided the selection of 78 individuals from Australia and east Indonesia for CR sequencing. A gene tree of these CR sequences, combined with published sequences from worldwide populations, contains two previously identified highland PNG clusters that do not include any Aboriginal Australians; the highland PNG clusters have coalescent time estimates of approximately 80,000 and 122,000 years ago, suggesting ancient isolation and genetic drift. SSO-type data indicate that 84% of the sample of PNG highlander mtDNA belong to these two clusters. In contrast, the Aboriginal Australian sequences are intermingled throughout the tree and cluster with sequences from multiple populations. Phylogenetic and multidimensional-scaling analyses of CR sequences and SSO types split PNG highland and Aboriginal Australian populations and link Aboriginal Australian populations with populations from the subcontinent of India. These mtDNA results do not support a close relationship between Aboriginal Australian and PNG populations but instead suggest multiple migrations in the peopling of Sahul. (+info)
Polymorphism at the merozoite surface protein-3alpha locus of Plasmodium vivax: global and local diversity.
Allelic diversity at the Plasmodium vivax merozoite surface protein-3alpha (PvMsp-3alpha) locus was investigated using a combined polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) protocol. Symptomatic patient isolates from global geographic origins showed a high level of polymorphism at the nucleotide level. These samples were used to validate the sensitivity, specificity, and reproducibility of the PCR/RFLP method. It was then used to investigate PvMsp3alpha diversity in field samples from children living in a single village in a malaria-endemic region of Papua New Guinea, with the aim of assessing the usefulness of this locus as an epidemiologic marker of P. vivax infections. Eleven PvMsp-3alpha alleles were distinguishable in 16 samples with single infections, revealing extensive parasite polymorphism within this restricted area. Multiple infections were easily detected and accounted for 5 (23%) of 22 positive samples. Pairs of samples from individual children provided preliminary evidence for high turnover of P. vivax populations. (+info)