Environmental Change and Human Health Case Studies I

The World Health Organization (WHO) has become increasingly concerned about effect of global environmental change on human health.1 In addition to climate change, biodiversity and natural disasters, there are a number of human interventions that are direct drivers of environmental change, such as land and agricultural practices, irrigation and dams and human behaviour.1 Impacts can be modified or exacerbated by a local population’s current vulnerability, such as population movement into an endemic area for a disease for which they have no immunity. Global changes, including an increase in trade and global warming, which act on the environment, are likely to impact on the evolution of pathogens and hence of diseases. For example, it is likely that climate change is likely to alter the geography of infectious diseases and pests, including the distribution of vector-borne diseases, such as Rift Valley fever, yellow fever, malaria, dengue and Chikungunya, which are highly sensitive to climatic conditions.1 Other diseases may also be influenced by climate, such as meningitis and cholera.2 Also, we have seen how changes to irrigation and dams have previously affected the distribution of diseases, such as schistosomiasis. This present book, Environmental Change and Human Health: Case Studies I, is a significant contribution to addressing these challenges. The Editor, Deon Canyon, presents a unique publication that is sure to assist professionals and students working in public health and environmental health, as well as related areas such as tropical health or environmental engineering. The main components of the book are an introductory chapter on “Biodiversity, environmental change and the web of life” and a series of case studies, which illustrate and inform the reader about these issues. The cases relate to diverse interests including cholera outbreaks globally, water quality and nutrient loading in the USA, schistosomiasis in China, neurocystercercosis in China, Nipah virus and Malaysia, Hantavirus and Argentina, pneumonic plague and the Congo, skin cancer and Mackay in Australia, the Toowoomba water crisis, schistosomiasis and Ghana, Chikungunya and the west Indian Ocean islands, Chagas’ disease and Guatemala. The major advantage as always with electronically published monographs is the full colour illustrations. This is an important online publication to add to your list of website bookmarks

A systematic review of research on outrigger canoe paddling and racing

Purpose: Research on outrigger canoe paddling performance is in its infancy and only began in the late 1990s. This paper systematically identified and reviewed previously published peer-reviewed articles and theses, and summarized the findings with the aim of defining the current state of knowledge on the sport. Method: Using a systematic review, searches were conducted on PubMed MEDLINE, Academic Search Premier, Cochrane Library databases and Google Scholar for articles published up to June 2014. A standard systematic review process was applied to sift abstracts and full texts to obtain and extract data on study characteristics, measurements and recommendations. Results: Twenty-seven articles by eleven lead authors were identified. There was fairly close consensus on anthropometrics, peak physiological measurements, stroke variables, injury prevalence and paddle design. Most non-injury studies relied on small data sets and had limited statistical power. Conclusions: The results identified in this review provide a starting point for more systematic research that identifies and quantifies performance predictors in outrigger canoe racing

A systematic review of research on outrigger canoe paddling and racing

Purpose: Research on outrigger canoe paddling performance is in its infancy and only began in the late 1990s. This paper systematically identified and reviewed previously published peer-reviewed articles and theses, and summarized the findings with the aim of defining the current state of knowledge on the sport. Method: Using a systematic review, searches were conducted on PubMed MEDLINE, Academic Search Premier, Cochrane Library databases and Google Scholar for articles published up to June 2014. A standard systematic review process was applied to sift abstracts and full texts to obtain and extract data on study characteristics, measurements and recommendations. Results: Twenty-seven articles by eleven lead authors were identified. There was fairly close consensus on anthropometrics, peak physiological measurements, stroke variables, injury prevalence and paddle design. Most non-injury studies relied on small data sets and had limited statistical power. Conclusions: The results identified in this review provide a starting point for more systematic research that identifies and quantifies performance predictors in outrigger canoe racing

Aquatic insect predators and mosquito control

Mosquitoes are serious biting pests and obligate vectors of many vertebrate pathogens. Their immature larval and pupal life stages are a common feature in most tropical and many temperate water bodies and often form a significant proportion of the biomass. Control strategies rely primarily on the use of larvicides and environmental modification to reduce recruitment and adulticides during periods of disease transmission. Larvicides are usually chemical but can involve biological toxins, agents or organisms. The use of insect predators in mosquito control has been exploited in a limited fashion and there is much room for further investigation and implementation. Insects that are recognized as having predatorial capacity with regard to mosquito prey have been identified in the Orders Odonata, Coleoptera, Diptera (primarily aquatic predators), and Hemiptera (primarily surface predators). Although their cpacity is affected by certain biological and physical factors, they could play a major role in mosquito control. Furthermore, better understanding for the mosquitoes-predators relationship(s) could probably lead to satisfactory reduction of mosquito-borne diseases by utilizing either these predators in control programs, for instance biological and/or integrated control, or their kairomones as mosquitoes’ovipoisting repellents. This review covers the predation of different insect species on mosquito larvae, predatorprey- habitat relationships, co-habitation developmental issues, survival and abundance, oviposition avoidance, predatorial capacity and integrated vector control

Deficient crisis-probing practices and taken-for-granted assumptions in health organisations

The practice of crisis-probing in proactive organisations involves meticulous and sustained investigation into operational processes and management structures for potential weaknesses and flaws before they become difficult to resolve. In health organisations, crisis probing is a necessary part of preparing to manage emerging health threats. This study examined the degree of pre-emptive probing in health organisations and the type of crisis training provided to determine whether or not they are prepared in this area. This evidence-based study draws on cross-sectional responses provided by executives from chiropractic, physiotherapy, and podiatry practices; dental and medical clinics; pharmacies; aged care facilities; and hospitals. The data show a marked lack of mandatory probing and a generalised failure to reward crisis reporting. Crisis prevention training is poor in all organisations except hospitals and aged care facilities where it occurs at an adequate frequency. However this training focuses primarily on natural disasters, fails to address most other crisis types, is mostly reactive and not designed to probe for and uncover key taken-for-granted assumptions. Crisis-probing in health organisations is inadequate, and improvements in this area may well translate into measurable improvements in preparedness and response outcomes

Community-based environmental health: should health be integrated with environment?

This publication does not have an abstrac

The effectiveness of deet and phytochemical repellents in the prevention of head lice (Pediculus capitis) transmission

Purpose of Study: With increasing global prevalence and awareness of pediculosis, the number of head lice repellents and preventatives has increased dramatically without quality assurance or control. Synthetic chemicals require scrutiny before they reach the market, however, phytochemicals are not covered by USEPA legislation and require no testing. This study compares the efficacy of several phytochemicals against DEET and lubricant controls to determine their efficacy in preventing head lice infestations.\ud \ud Methods: The efficacy of 10 repellents was assessed in 3 experiments. Experiment 1 investigated the likelihood that a louse would transfer from an untreated hair onto a passing hair (26 reps). Experiment 2 investigated irritancy in terms of tropotaxis, klinokinesis and orthokinesis (20 reps). This involved placing lice on the center of a hair that was coated in repellent on both ends. Experiment 3 investigated repellent and antifeedant properties of repellents applied to human skin. Adult lice (610) recently harvested from school children and maintained on blood were used. \ud \ud Results & Discussion: Chi-square exact tests showed overall models in all experiments were significant (p<0.01). In Experiment 1, application of repellent to hair inhibited lice transfer by 35-65% with lubrication responsible for 40%. In Experiment 2, tropotaxis in response to repellent treated hair was minimal except to coconut oil. Orthokinesis and klinokinesis were similar for most repellents with coconut, neem and scalp oil performing well. In Experiment 3, most repellents applied on skin did not inhibit louse movement with most lice remaining on treated skin and bloodfeeding. Tea tree oil was the most effective repelling 55%. Less effective repellents were Lavender, Scalp Oil, Coconut, DEET Peppermint (10-35%).\ud \ud Side-effect - dispersal Lice are thought to use activity-related human hosts as “rooms in their house” rather than to prefer a particular host (Speare and Canyon, unpublished). Repellents can shorten the residency period and increase dispersal within the “room” or between “rooms”.\ud \ud Antifeedant Efficacy: Will lice bloodfeed in the presence of a repellent? Most repellents were not effective with most lice bloodfeeding. Some inhibition of feeding was caused by lavender (35%) tea tree (25%) and neem/citronella (5%)\ud \ud All the so-called repellents tested failed to act as repellents in any significant degree.\ud \ud Several phytochemical oils outperformed DEET in every experiment indicating some promise.\ud \ud Future research will focus on discovery of novel phytochemical repellents.\u

Head lice repellents

[Extract]\ud The failure of pediculicide products in many countries\ud (Chapter 6.4.) has resulted in increased consideration of preventative methods, which most commonly involve the use of repellents. In general, insect repellents are used as a means of personal protection against biting arthropods. At\ud present, one of the most effective methodologies to prevent transmission of insect-borne disease is to use repellents, which over-sensitise the chemoreceptive organs of the vector and disorient it from seeking a blood meal from a human host. Lice repellents were thus initially drawn from the arsenal of chemicals commonly found to be effective\ud against other insects such as mosquitoes and biting flies; however little empirical evidence exists. Herbal lore often promotes the use of essential oils, however, in most cases, little more than anecdotal evidence exists and empirical evidence does not tend to substantiate claims of efficacy or is contradictory. With increasing global prevalence of pediculosis and accompanying increasing awareness, the number of head lice repellents and preventatives available over the counter has increased dramatically without any quality assurance or control. Although synthetic chemicals require scrutiny before they reach the market, botanical formulations and phytochemicals require no testing for either efficacy or toxicity