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Strongyloides stercoralis has one of the most complex life cycles of the human-infecting nematodes. A common misconception in medical and public health professions is that S. stercoralis in its biology is akin to other intestinal nematodes, such as the hookworms. Despite original evidence provided by medical and veterinary research about this unique helminth, many assumptions have entered the scientific literature. This helminth is set apart from others that commonly affect humans by (a) the internal autoinfective cycle with autoinfective larvae randomly migrating through tissue, parthenogenesis, and the potential for lifelong infection in the host, the profound pathology occurring in hyperinfection and systemic manifestations of strongyloidiasis, and (b) a limited external cycle with a single generation of free-living adults. This paper aims to review and discuss original research on the unique life cycle of S. stercoralis that distinguishes it from other helminths and highlight areas where increased understanding of the parasite’s biology might lead to improved public health prevention and control strategies.

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Community-based health promotion often emphasizes elements of empowerment, participation, multidisciplinary collaboration, capacity building, equity and sustainable development. Such an emphasis may be viewed as being in opposition to equally powerful notions of evidence-based decision making and accountability, and with funders' and government decision-makers' preoccupation with measuring outcomes. These tensions may be fuelled when community practitioners and lay participants feel evaluations are imposed upon them in a manner that fails to appreciate the uniqueness of their community, its programme, and practitioners' skills and experience. This paper attempts to provide an approach that depicts evaluation as being mutually beneficial to both funders/government and practitioners. First, a values stance for health promotion, termed a 'salutogenic' orientation, is proposed as a foundation for the evaluation of community-based health promotion. Secondly, we discuss possible objects of interest, the first component of an evaluation. We then discuss the spirit of the times and its implications for community-based health promotion. Finally, we address the key question of setting standards. A typology of standards is presented. Arbitrary, experiential and utility standards are based on perceived needs and priorities of practitioners, lay participants or professional decision-makers. Historical, scientific and normative standards are driven by empirical, objective data. Propriety and feasibility standards are those wherein the primary concern is for consideration of resources, policies, legislation and administrative factors. The 'model' standards approach is presented as an exemplar of a combined approach that incorporates elements of each of the other standards. We argue that the 'optimal' standard for community-based health promotion depends on the setting and the circumstances. There is no 'magic bullet', 'one-size-fits-all' or 'best' standard. Further, we argue that standards should be set from an inclusive, salutogenic orientation. This approach offers a means of creating a situation in which policy-makers and funders are more supportive of evaluation designs that fit with community realities, and community stakeholders are more capable and consistent in rigorously evaluating community-based health promotion programmes and policies.