136 research outputs found

    Role of environmental poliovirus surveillance in global polio eradication and beyond

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    Environmental poliovirus surveillance (ENV) means monitoring of poliovirus (PV) transmission in human populations by examining environmental specimens supposedly contaminated by human faeces. The rationale is based on the fact that PV-infected individuals, whether presenting with disease symptoms or not, shed large amounts of PV in the faeces for several weeks. As the morbidity:infection ratio of PV infection is very low, this fact contributes to the sensitivity of ENV which under optimal conditions can be better than that of the standard acute flaccid paralysis (AFP) surveillance. The World Health Organization has included ENV in the new Strategic Plan of the Global Polio Eradication Initiative for years 2010-2012 to be increasingly used in PV surveillance, supplementing AFP surveillance. In this paper we review the feasibility of using ENV to monitor wild PV and vaccine-derived PV circulation in human populations, based on global experiences in defined epidemiological situation

    Treatment of Travel Expenses by Golf Course Patrons: Sunk or Bundled Costs and the First and Third Laws of Demand

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    To attract golf patrons, sport managers must understand consumption patterns of the golfer. Importantly, the treatment of travel costs must be understood. According to the Alchian-Allen (1964) theorem, golfers treat travel costs as bundled costs (third law of economic demand) whereas classical consumer theory indicates that golfers treat travel costs as sunk costs (first law of economic demand). The purpose of this study was to determine if golf patrons treated travel costs as sunk costs or if they treated travel costs as a bundled cost. Data from a survey of course patrons in Ohio support the treatment of travel costs as bundled costs by golf course patrons, especially those classified as tourists. The strong, positive correlation found between distance traveled and the cost of greens fees enables managers to utilize geographic segmentation in choosing to whom to market their course based upon their product’s price compared to area competitors

    Adaptive Management and the Value of Information: Learning Via Intervention in Epidemiology

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    Optimal intervention for disease outbreaks is often impeded by severe scientific uncertainty. Adaptive management (AM), long-used in natural resource management, is a structured decision-making approach to solving dynamic problems that accounts for the value of resolving uncertainty via real-time evaluation of alternative models. We propose an AM approach to design and evaluate intervention strategies in epidemiology, using real-time surveillance to resolve model uncertainty as management proceeds, with foot-and-mouth disease (FMD) culling and measles vaccination as case studies. We use simulations of alternative intervention strategies under competing models to quantify the effect of model uncertainty on decision making, in terms of the value of information, and quantify the benefit of adaptive versus static intervention strategies. Culling decisions during the 2001 UK FMD outbreak were contentious due to uncertainty about the spatial scale of transmission. The expected benefit of resolving this uncertainty prior to a new outbreak on a UK-like landscape would be £45–£60 million relative to the strategy that minimizes livestock losses averaged over alternate transmission models. AM during the outbreak would be expected to recover up to £20.1 million of this expected benefit. AM would also recommend a more conservative initial approach (culling of infected premises and dangerous contact farms) than would a fixed strategy (which would additionally require culling of contiguous premises). For optimal targeting of measles vaccination, based on an outbreak in Malawi in 2010, AM allows better distribution of resources across the affected region; its utility depends on uncertainty about both the at-risk population and logistical capacity. When daily vaccination rates are highly constrained, the optimal initial strategy is to conduct a small, quick campaign; a reduction in expected burden of approximately 10,000 cases could result if campaign targets can be updated on the basis of the true susceptible population. Formal incorporation of a policy to update future management actions in response to information gained in the course of an outbreak can change the optimal initial response and result in significant cost savings. AM provides a framework for using multiple models to facilitate public-health decision making and an objective basis for updating management actions in response to improved scientific understanding

    Understanding the Impact of Male Circumcision Interventions on the Spread of HIV in Southern Africa

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    BACKGROUND: Three randomised controlled trials have clearly shown that circumcision of adult men reduces the chance that they acquire HIV infection. However, the potential impact of circumcision programmes--either alone or in combination with other established approaches--is not known and no further field trials are planned. We have used a mathematical model, parameterised using existing trial findings, to understand and predict the impact of circumcision programmes at the population level. FINDINGS: Our results indicate that circumcision will lead to reductions in incidence for women and uncircumcised men, as well as those circumcised, but that even the most effective intervention is unlikely to completely stem the spread of the virus. Without additional interventions, HIV incidence could eventually be reduced by 25-35%, depending on the level of coverage achieved and whether onward transmission from circumcised men is also reduced. However, circumcision interventions can act synergistically with other types of prevention programmes, and if efforts to change behaviour are increased in parallel with the scale-up of circumcision services, then dramatic reductions in HIV incidence could be achieved. In the long-term, this could lead to reduced AIDS deaths and less need for anti-retroviral therapy. Any increases in risk behaviours following circumcision, i.e. 'risk compensation', could offset some of the potential benefit of the intervention, especially for women, but only very large increases would lead to more infections overall. CONCLUSIONS: Circumcision will not be the silver bullet to prevent HIV transmission, but interventions could help to substantially protect men and women from infection, especially in combination with other approaches

    A Model of Multidestination Travel: Implications for Marketing Strategies

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    Because tourists derive utility from the enjoyment of destination characteristics, Lancaster's approach is putatively appropriate to address the particular structure of the tourism industry. Most research efforts regarding tourism destination, including those applying Lancaster's model, specifically address the choice of a single destination. This article is intended to explain multiple destination choice using Lancaster's characteristics model and a discussion of model implications of some marketing strategies for destinations as well as for tour operators. The model developed herein explains that packages of multiple destinations can create preferable combinations of characteristics for certain travelers. Furthermore, the model provides useful strategies for tour operators in Combining destinations into a travel menu or package

    Pricing and the psychology of consumption

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    Most executives know how pricing influences the demand for a product, but few of them realize how it affects the consumption of a product. In fact, most companies don't even believe they can have an effect on whether customers use products they have already paid for. In this article, the authors argue that the relationship between pricing and consumption lies at the core of customer strategy. The extent to which a customer uses a product during a certain time period often determines whether he or she will buy the product again. So pricing tactics that encourage people to use the products they've paid for help companies build long-term relationships with customers. The link between pricing and consumption is clear: People are more likely to consume a product when they are aware of its cost. But for many executives, the idea that they should draw consumers' attention to the price that was paid for a product or service is counterintuitive. Companies have long sought to mask the costs of their goods and services in order to boost sales. And rightly so - if a company fails to make the initial sale, it won't have to worry about consumption. So to promote sales, health club managers encourage members to get the payment out of the way early; HMOs encourage automatic payroll deductions; and cruise lines bundle small, specific costs into a single, all-inclusive fee. The problem is, by masking how much a buyer has spent on a given product, these pricing tactics decrease the likelihood that the buyer will actually use it. This article offers some new approaches to pricing - how and when to charge for goods and services-that may boost consumption
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