Thesis (M. Phil.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 150-157).

Zugl.: Konstanz, Univ., Diss., 2007

Emerging diseases are an increasingly important public health problem. This research investigates space-time disease surveillance for emerging infectious diseases. A system was developed in Sri Lanka monitoring clinical diagnoses in cattle, poultry and buffalo. Veterinarians submitted surveys using mobile phones and GPS. This surveillance system proved to be both feasible and acceptable and provided timely information on animal health patterns in Sri Lanka. A critical review of software and methods for space-time disease surveillance provides guidance on the selection and implementation of appropriate analytic methods for surveillance data. For the data collected in this research, a hidden Markov model is developed which estimates region-specific prevalence estimates after controlling for sentinel-level factors. The use of cluster detection methods in surveillance research is demonstrated using data from an outbreak of suspected leptospirosis in Sri Lanka in 2005-2009. / Graduate

No description available.

published_or_final_version / abstract / Ecology and Biodiversity / Doctoral / Doctor of Philosophy

Ph. D. : Hist. : Yale University (Conn.) : 198? / Texte remanié de : Doct.-Diss. : Philosophy : New Haven, Yale university : 1980. Bibliogr. p. 371-382 Notes bibliogr. Index.

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Anopheles species composition and relative seasonal abundance were measured in an irrigated division (low historical malaria incidence) and in a rain-fed division (high historical malaria incidence) of southern Sri Lanka. Twelve species of anophelines were represented in adult and larval collections with Anopheles vagus Donitz being the most abundant. In cattle-baited net trap collections, Anopheles adults were significantly more abundant in the irrigated division than in the rain-fed division. In pyrethrum-spray sheet collections, cattle-baited but trap collections and larval collections, Anopheles abundance was significantly greater in the rain-fed division. Houses were of poorer construction in the rain-fed division, where pyrethrum-spray sheet collections consisted mainly of Anopheles subpictus Grassi (98%) and Anopheles culicifacies Giles (2%). Hut trap collections also consisted mainly of An. subpictus (88%) and An. culicifacies (7%). Net trap collections consisted mainly of An. vagus (43%) and Anopheles peditaeniatus Leicester (31%). Larval collections also consisted of An. peditaeniatus (24%) and An. vagus (21%). Weak associations were found between species abundance and environmental factors explored in this study (e.g., vegetation, water quality, sunlight exposure). The greater malaria risk in the rain-fed division is due in part to the occurrence of potential vectors in relatively higher numbers.

No description available.

This study was conducted to understand the interactions between irrigation water management and water quality (agro-ecological interactions). The Uda Walawe basin, in Southern Sri Lanka was chosen as the study area. Fluctuations in water quality, especially microbiological water quality, affect human health. Since the source of domestic water (drinking and washing) in this region is from the irrigation system, there is a concern for the human health effects. All the potential water sources and the water use habits of the community were identified. The water quality of these sources was then monitored for a period of 5 months (August--December 2000). Second, the water management of the Uda Walawe irrigation system was linked to the differences in water quality. The best quality water was found to come from the shallow wells (seepage water from the irrigation system). Both quantity and quality of the water were shown to fluctuate with canal construction (earthen or concrete) and irrigation water management.