Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024530 (malaria)
 44,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A survey of adult mosquitoes was done during 1986-1987 in an area undergoing irrigation development in the Mahaweli Project of Sri Lanka. The study encompassed two 12-mo phases of settlement and irrigation, respectively. Diurnal human bait catches yielded 1,427 female mosquitoes in 27 species. Nocturnal collections (human bait, CDC light traps, indoor resting catches) produced a total of 30,491 females in 67 species. Comparisons with an earlier survey in the predevelopment forest showed that the diurnal human biting abundance of Aedes albopictus (Skuse) remained stable, whereas the abundance of Ae. novalbopictus Barraud and Ae. w-albus Theobald declined drastically after development. Man-mosquito contact increased substantially for nocturnally active Anopheles annularis van der Wulp, An. subpictus Grassi, Mansonia uniformis (Theobald), Culex tritaeniorhynchus Giles, and Cx. quinefasciatus Say and decreased for Ma. annulifera (Theobald) and Cx. gelidus Theobald. A small increase occurred in An. culicifacies Giles, An. vagus Donitz, An. varuna lyengar, Cx. fuscocephala Theobald, and Cx. whitmorei (Giles); Cx. pseudovishnui Colless decreased. The effect of changes in mosquito abundance on the increased transmission of malaria and Japanese encephalitis is discussed.
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PMID:Survey of adult mosquitoes (Diptera: Culicidae) during irrigation development in the Mahaweli Project, Sri Lanka. 167 84

The incubation period for malaria parasites within the mosquito is exquisitely temperature-sensitive, so that temperature is a major determinant of malaria risk. Epidemiological models are increasingly used to guide allocation of disease control resources and to assess the likely impact of climate change on global malaria burdens. Temperature-based malaria transmission is generally incorporated into these models using mean monthly temperatures, yet temperatures fluctuate throughout the diurnal cycle. Here we use a thermodynamic malaria development model to demonstrate that temperature fluctuation can substantially alter the incubation period of the parasite, and hence malaria transmission rates. We find that, in general, temperature fluctuation reduces the impact of increases in mean temperature. Diurnal temperature fluctuation around means >21 degrees C slows parasite development compared with constant temperatures, whereas fluctuation around <21 degrees C speeds development. Consequently, models which ignore diurnal variation overestimate malaria risk in warmer environments and underestimate risk in cooler environments. To illustrate the implications further, we explore the influence of diurnal temperature fluctuation on malaria transmission at a site in the Kenyan Highlands. Based on local meteorological data, we find that the annual epidemics of malaria at this site cannot be explained without invoking the influence of diurnal temperature fluctuation. Moreover, while temperature fluctuation reduces the relative influence of a subtle warming trend apparent over the last 20 years, it nonetheless makes the effects biologically more significant. Such effects of short-term temperature fluctuations have not previously been considered but are central to understanding current malaria transmission and the consequences of climate change.
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PMID:Understanding the link between malaria risk and climate. 1970 96

Vector-borne diseases are particularly responsive to changing environmental conditions. Diurnal temperature variation has been identified as a particularly important factor for the development of malaria parasites within vectors. Here, we conducted a survey across France, screening populations of the house sparrow (Passer domesticus) for malaria (Plasmodium relictum). We investigated whether variation in remotely-sensed environmental variables accounted for the spatial variation observed in prevalence and parasitemia. While prevalence was highly correlated to diurnal temperature range and other measures of temperature variation, environmental conditions could not predict spatial variation in parasitemia. Based on our empirical data, we mapped malaria distribution under climate change scenarios and predicted that Plasmodium occurrence will spread to regions in northern France, and that prevalence levels are likely to increase in locations where transmission already occurs. Our findings, based on remote sensing tools coupled with empirical data suggest that climatic change will significantly alter transmission of malaria parasites.
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PMID:Predictions of avian Plasmodium expansion under climate change. 2335 33