Author : Laurens Aarnoud Manning
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (93 download)
Book Synopsis The Impact of Malaria on Severe Illness and Mortality in Papua New Guinean Children by : Laurens Aarnoud Manning
Download or read book The Impact of Malaria on Severe Illness and Mortality in Papua New Guinean Children written by Laurens Aarnoud Manning and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: [Truncated abstract] In Papua New Guinea (PNG), nearly 10% of children will die before their 5th birthday. The absence of contemporary data and the lack of vital reporting mechanisms in PNG result in substantial uncertainty in the overall estimates of mortality. This uncertainty is compounded when cause- or pathogen-specific mortality is estimated. This thesis focuses on malaria, caused by the parasites Plasmodium falciparum and P. vivax that are endemic to many coastal areas of PNG, and its impact on severe childhood illness and mortality. Official estimates suggest that malaria accounts for 15% of deaths in children older than 1 month across the country. However, the studies on which mortality estimates are based were performed in areas without intense malaria transmission. Therefore they may not accurately reflect the true impact of malaria in coastal populations, where transmission is hyperendemic and P. vivax is co-transmitted with P. falciparum. As in African settings, where malaria transmission is also high, the burden of severe malarial disease and subsequent mortality in PNG's coastal populations is primarily borne by young children and pregnant women. In PNG, P. vivax is also transmitted intensely and is an important difference with malaria in Africa where P. falciparum accounts for the vast majority of malaria morbidity. P. vivax itself is recognised as a cause of severe illness and mortality, whilst published data on mixed infections with P. vivax are conflicting, with studies describing abrogated, or augmented clinical effects in patients with both species present. Another key difference between the spectrum of malaria disease in Africa when compared with PNG is that, although crude-mortality estimates and epidemiological data implicate malaria as an important factor in severe illness and mortality, previous community and hospital based observational studies in PNG and elsewhere in Oceania have reported very low mortality rates in children suffering from severe malaria. These apparently low severe malaria mortality rates have led to a number of explanations. Local genetic polymorphisms and possible cross-protective immunity provided by exposure to P. vivax during infancy have been suggested in previous studies. Some of the total genetic variability to malaria may be accounted for by alpha-thalassaemia and other known red blood cell polymorphisms such as South Asian Ovalocytosis commonly found in coastal Melanesians. The presence of such polymorphisms suggests that malaria has exerted a strong selective genetic effect on these populations. Equally, variation in the methods of clinical assessment, the quality of parasitological diagnosis of malaria or the extent to which other infectious diseases are excluded could also account for differences in malaria mortality rates. Finally over- or mis-diagnosis may be other factors accounting for this variability. Bacterial meningitis, viral encephalitis, pneumonia, bacterial sepsis and non-malarial severe anaemia have similar clinical features that overlap those of malaria such as coma, seizures, breathlessness, circulatory compromise and pallor. Consequently, where good quality laboratory or radiographic facilities are not available, over-diagnosis of severe malaria is the rule rather than the exception and other conditions are overlooked, leading to inappropriate management...
