No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

1. Drug resistant strains of <I>P. falciparum</I> are becoming increasingly prevalent in most malaria endemic areas of the world, complicating treatment and prophylaxis. The prevalence of <I>P. falciparum</I> was assessed in six villages in the Punjab, Pakistan. The study was carried out during the months of August-October, 1992. A total of 566 people was surveyed. Fifty blood samples from positive plasmodial cases were analysed. Overall <I>P. falciparum</I> comprised the highest proportion of cases (62.39%) followed by <I>P. vivax</I> (36.7%) and mixed infection (0.85%) and mixed infection (0.85%). The slide positivity rate was 20.6%. The prevalence rate of plasmodial infection in the combined population was 3.8/1000. This is higher than the reported national prevalence rate of 0.7/1000 (WHO, 1992). 2. Sensitivity to chloroquine of the cultured isolates was carried out by [³H]hypoxanthine incorporation and by microscopical assessment. 3. In mammalian cells mixed function oxidase systems of which cytochrome P450 is the terminal oxidase are responsible for the metabolism of a whole variety of structurally unrelated xenobiotics, which include antimalarial drugs. 4. An alternative method of resistance was investigated by examining the relationship between resistance and chloroquine accumulation and efflux in <I>P. falciparum</I> using [³H]chloroquine. 5. Verapamil, a calcium channel blocker has been shown to reverse completely chloroquine-resistance in chloroquine-resistant <I>P. falciparum</I> isolates. 6. The digestive vacuole is thought to be the site of action of chloroquine on the malarial parasite. 7. The ultimate target of chloroquine and related drugs remains unclear. Drug resistance may be a result of decreased vacuolar accumulation in chloroquine-resistant parasites.

Doctor of Philosophy / Department of Geography / Douglas G. Goodin / The malaria burden has decreased in Nepal between 1988 and 2013. However, there are challenges to completely eradicating the disease. Malaria patterns in a few endemic districts have not changed, and higher malaria case rates have been detected within districts which otherwise were categorized as low endemic areas. Underlying biophysical, socioeconomic, and behavioral factors influence malaria transmission and create region-specific patterns. This research employs various concepts, tools, and techniques to understand the geographic distribution of malaria in Nepal. In this research, malaria prevalence patterns were investigated at multiple spatial and temporal scales. The study identifies malaria hot spots, describes their characteristics and examines shifts in malaria hot spots between 1988 and 2013. Within that 26-year time span, 267,121 confirmed malaria cases were recorded. Thirty-nine of 75 districts were identified as malaria hot spots in Nepal. Based on the frequency, persistence and proportion of caseloads each year, the identified hotspots were grouped into five categories; stable, disappearing, emerging, reemerging, and intermittent. The research also investigated the relationship between climatic factors and malaria frequency, and found that temperature and precipitation during the monsoon and non-monsoon seasons played significant roles in determining the absence and presence of malaria and low and high frequency of malaria distribution at the district level. The dissertation also presents the findings of a study that investigated malaria–related knowledge, perceptions and practices among adults in Nepal, specifically knowledge about its signs, symptoms, consequences, and the availability and use of prevention tools. Although a significant portion of respondents had heard of malaria there was wide variation in their knowledge about specific information related to the disease. Locality, age, household size, education, and income were significantly associated with malaria–related knowledge.