Paying for urban services : a study of water vending and willingness to pay for water in Onitsha, Nigeria

This paper presents a case study of water vending in Onitsha, Nigeria, one of the most important market towns in West Africa. It illustrates that a rapid reconnaissance survey of water vending activities and the willingness of households to pay for improved water services can yield valuable information for water supply planning and unexpected policy insights. The vast majority of Onitsha obtains its water from an elaborate and well-organized water vending system which has been created and is operated by the private sector. Approximately 275 tanker trucks purchase water from about 20 private boreholes and then sell it to households and businesses equipped with water storage facilities. Many of the households which purchase water from tanker trucks resell the water by the bucket to individuals who cannot afford large storage tanks or who cannot be reached by tanker trucks. During the dry season households obtain approximately 2.96 million gallons per day (mgd) from the water vending system, for which they pay about US$28,000. In 1987 the public water utility was supplying about 1.5 mgd during the dry season and only managed to collect US$1,100 in revenues. In the rainy season the revenues from water vendor sales were still several times higher than the water utility. On an annual basis, households in Onitsha are already paying water vendors over twice the operation and maintenance costs of a piped distribution system.Town Water Supply and Sanitation,Water Supply and Sanitation Governance and Institutions,Water and Industry,Water Conservation,Water Use

An economic reappraisal of the Melamchi water supply project – Kathmandu, Nepal

This paper examines whether the benefits of the Melamchi water supply project in Nepal are likely to exceed its costs, assuming that high-quality municipal water services can be delivered to households and firms in the urbanized part of the Kathmandu Valley. Monte Carlo simulations are used to explore the sensitivity of the net present value and economic internal rate of return calculations to a wide range of assumptions and input parameters.We find that extreme assumptions are not required to generate large differences in economic feasibility; quite plausible differences in the values of some key parameters can lead to large differences in the economic attractiveness of the project. The results reveal that the three most important influences on net present value and economic internal rate of return are: (i) the discount rate and discounting procedure; (ii) the magnitude of monthly benefits for households connected to the new water system; and (iii) the annual growth rate in monthly benefits of connected households after the project comes on line. Our contribution lies in illustrating, with an actual case study in a developing country, the degree to which cost-benefit calculations of large infrastructure projects are influenced by key economic modeling assumptions and input parameters.info:eu-repo/semantics/publishedVersio

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

Selecting Optimal Prices and Outpost Locations for Rural Vaccination Campaigns

A contingent valuation survey (willingness-to-pay study) was conducted in 2004 to measure household demand for typhoid vaccines in a rural township in China with approximately 54,000 people living in 141 villages. The results showed that travel distance to vaccination sites and vaccination price affected the private demand for typhoid fever vaccinations. The number and location of vaccination outposts are thus important decision variables for a new vaccination campaign that is under consideration. This article develops and applies an optimization model for planning vaccination programs. The model determines what price to charge, how many vaccination outposts to use, where to locate them, and what capacities they need. The model uses demand information from the contingent valuation survey and cost information from similar vaccination campaigns in China and assumes that costs must be covered by user fees. The model determined that the number of outposts to use for maximizing coverage was fourteen, which would make average one-way travel distance for users about 0.6 km. The optimal vaccination price was USD 1.25, and about 87 percent of the population would be vaccinated. A suboptimal solution of the model showed that only 6 outposts instead of 14 would probably vaccinate about 83 percent of the population, and the price could be reduced to USD 0.83. The model is easy to use and solve and can be applied to different size regions. </jats:p