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The mosquito-borne disease (malaria) imposes significant challenges on human health, healthcare systems, and economic growth/productivity in many countries. This study develops and analyzes a model to understand the interplay between malaria dynamics, economic growth, and transient events. It uncovers varied effects of malaria and economic parameters on model outcomes, highlighting the interdependence of the reproduction number () on both malaria and economic factors, and a reciprocal relationship where malaria diminishes economic productivity, while higher economic output is associated with reduced malaria prevalence. This emphasizes the intricate interplay between malaria dynamics and socio-economic factors. The study offers insights into malaria control and underscores the significance of optimizing external aid allocation, especially favoring an even distribution strategy, with the most significant reduction observed in an equal monthly distribution strategy compared to longer distribution intervals. Furthermore, the study shows that controlling malaria in high mosquito biting areas with limited aid, low technology, inadequate treatment, or low economic investment is challenging. The model exhibits a backward bifurcation implying that sustainability of control and mitigation measures is essential even when is slightly less than one. Additionally, there is a parameter regime for which long transients are feasible. Long transients are critical for predicting the behavior of dynamic systems and identifying factors influencing transitions; they reveal reservoirs of infection, vital for disease control. Policy recommendations for effective malaria control from the study include prioritizing sustained control measures, optimizing external aid allocation, and reducing mosquito biting.
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Puddles, creeks, and drainage: connected histories of water and malaria in Zanzibar, 1910–2021
Abstract This article draws on a combination of archival and oral sources in order to highlight the connected histories of water and malaria on the Indian Ocean island of Zanzibar (Unguja) over the past century. We argue that in both the past and the present, water and malaria have been deeply connected, through the lifecycle of the disease, through control measures enacted, and in how Zanzibari residents continue to talk about the relationship between rain, puddles, stagnant water, and disease. Archival sources show that between roughly 1913 and 1957, the British colonial government managed malaria by managing water. That entailed a focus on watery breeding sites that included attention to both the micro: cattle hoofprints, and the macro: a multi-decade drainage of the tidal creek and surrounding swamp. These water-based malaria control efforts were limited in their efficacy by being geographically restricted to urban Zanzibar Town, and often limited to just the Stone Town area. 98 interviews conducted with Zanzibaris about malaria indicate that people continue to draw strong connections between malaria and the environment (mazingira), and that they most commonly discuss water’s relationship with malaria in terms of puddles (dimbwi/madimbwi), small puddles (kidimbwi/vidimbwi) and stagnant water (maji yaliyotuama).
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- Award ID(s):
- 1844715
- PAR ID:
- 10532922
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Water History
- Volume:
- 16
- Issue:
- 1
- ISSN:
- 1877-7236
- Format(s):
- Medium: X Size: p. 65-95
- Size(s):
- p. 65-95
- Sponsoring Org:
- National Science Foundation
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