Katherine Pond

An assessment of the costs and benefits of interventions aimed at improving rural community water supplies in developed countries

We report a cost benefit analyses (CBA) for water interventions in rural populations of developed country sub-regions. A Bayesian belief network was used to estimate the cost benefit ratio using Monte Carlo simulation. Where possible we used input data from recently published primary research or systematic reviews. Otherwise variables were derived from previous work in the peer-reviewed or grey literature. For these analyses we considered the situation of people with small and very small community supplies that may not be adequately managed. For the three developed country sub-regions Amr-A (America region A), Eur-A (European region A) and Wpr-A (Western Pacific region A), we estimate the costs of acute diarrhoeal illness associated with small community supplies to be U

Risk factors for transmission of Ebola or Marburg virus disease: a systematic review and meta-analysis

4671 million (95% CI 1721-9592), the capital costs of intervention to be USD 13703 million (95% CI 6670-20735), additional annual maintenance to be USD 804 million (95%CI 359-1247) and the CB ratio to be 2.78 (95%CI 0.86-6.5). However, we also estimated the cost of post infectious irritable bowel syndrome (IBS) following drinking water-associated acute gastroenteritis to be USD 11896 million (95%CI 3118-22657). When the benefits of reduced IBS are added to the analysis the CB ratio increases to 9.87 (95%CI 3.34-20.49). The most important driver of uncertainty was the estimate of the cost of illness. However, there are very few good estimates of costs in improving management of small rural supplies in the literature. Investments in drinking-water provision in rural settings are highly cost beneficial in the developed world. In the developed world, the CB ratio is substantially positive especially once the impact of IBS is included.

The effect of two mechanical beach grooming strategies on Escherichia coli density in beach sand at a southwestern Lake Michigan beach

Abstract Background: The Ebola virus disease outbreak that started in Western Africa in 2013 was unprecedented because it spread within densely populated urban environments and affected many thousands of people. As a result, previous advice and guidelines need to be critically reviewed, especially with regard to transmission risks in different contexts. Methods: Scientific and grey literature were searched for articles about any African filovirus. Articles were screened for information about transmission (prevalence or odds ratios especially). Data were extracted from eligible articles and summarized narratively with partial meta-analysis. Study quality was also evaluated. Results: A total of 31 reports were selected from 6552 found in the initial search. Eight papers gave numerical odds for contracting filovirus illness; 23 further articles provided supporting anecdotal observations about how transmission probably occurred for individuals. Many forms of contact (conversation, sharing a meal, sharing a bed, direct or indirect touching) were unlikely to result in disease transmission during incubation or early illness. Among household contacts who reported directly touching a case, the attack rate was 32% [95% confidence interval (CI) 26–38%]. Risk of disease transmission between household members without direct contact was low (1%; 95% CI 0–5%). Caring for a case in the community, especially until death, and participation in traditional funeral rites were strongly associated with acquiring disease, probably due to a high degree of direct physical contact with case or cadaver. Conclusions: Transmission of filovirus is unlikely except through close contact, especially during the most severe stages of acute illness. More data are needed about the context, intimacy and timing of contact required to raise the odds of disease transmission. Risk factors specific to urban settings may need to be determined.

Presence and Persistence of Ebola or Marburg Virus in Patients and Survivors: A Rapid Systematic Review

The influence of indicator bacteria associated with beach sands on recreational water quality has become increasingly recognized. Constant wave action may serve as a transport mechanism for delivering bacterial organisms to surface waters resulting in an increased frequency of dry weather advisories. The ability to reduce the concentration of these organisms may serve to improve recreational water quality. To date, few researchers have explored anthropogenic factors affecting the content of Escherichia coli in beach sands. This study explored the influence of mechanical beach grooming on in situ populations of Escherichia coli at a southwestern Lake Michigan beach to determine if an alteration in current beach management practices would serve to reduce the number of dry weather advisories in this community. Preliminary studies conducted during 2001 demonstrated that professional grooming significantly increased Escherichia coli content in beach sands relative to non-groomed or hand raked plots (p < 0.001). This data also suggested that deeper grooming might reduce differences between groomed and non-groomed areas. Subsequently, two mechanical grooming techniques were compared at Racine, WI in 2002: groomed to a depth of 5 to 7 cm with leveling of beach sands and groomed to a depth of 7 to 10 cm without leveling. Escherichia coli content between treatments were significantly correlated (p < 0.009). The density of the bacterium in deeper groomed/unleveled sands was significantly lower in visibly moist or wet but not dry sands (p = 0.038). In 2003, the manner in which beach sands were maintained using the mechanical beach groomer was altered and a follow-up study conducted. A 30 percent reduction in the number of poor water quality advisories due to dry weather events was achieved as a result of these measures. These results demonstrate that mechanical beach grooming may affect Escherichia coli content in beach sands, a potential source of non-point pollution to recreational waters.

Safe Management of Shellfish and Harvest Waters

Background The 2013–15 Ebola outbreak was unprecedented due to sustained transmission within urban environments and thousands of survivors. In 2014 the World Health Organization stated that there was insufficient evidence to give definitive guidance about which body fluids are infectious and when they pose a risk to humans. We report a rapid systematic review of published evidence on the presence of filoviruses in body fluids of infected people and survivors. Methods Scientific articles were screened for information about filovirus in human body fluids. The aim was to find primary data that suggested high likelihood of actively infectious filovirus in human body fluids (viral RNA). Eligible infections were from Marburg virus (MARV or RAVV) and Zaire, Sudan, Taï Forest and Bundibugyo species of Ebola. Cause of infection had to be laboratory confirmed (in practice either tissue culture or RT-PCR tests), or evidenced by compatible clinical history with subsequent positivity for filovirus antibodies or inflammatory factors. Data were extracted and summarized narratively. Results 6831 unique articles were found, and after screening, 33 studies were eligible. For most body fluid types there were insufficient patients to draw strong conclusions, and prevalence of positivity was highly variable. Body fluids taken >16 days after onset were usually negative. In the six studies that used both assay methods RT-PCR tests for filovirus RNA gave positive results about 4 times more often than tissue culture. Conclusions Filovirus was reported in most types of body fluid, but not in every sample from every otherwise confirmed patient. Apart from semen, most non-blood, RT-PCR positive samples are likely to be culture negative and so possibly of low infectious risk. Nevertheless, it is not apparent how relatively infectious many body fluids are during or after illness, even when culture-positive, not least because most test results come from more severe cases. Contact with blood and blood-stained body fluids remains the major risk for disease transmission because of the known high viral loads in blood.

Microbiological analysis of selected coastal bathing waters in the U.K., Greece, Italy and Spain

Developed from an expert workshop convened by the World Health Organization and US Environmental Protection Agency, Safe Management of Shellfish and Harvest Waters provides a thorough review of the issues surrounding public health concerns associated with shellfish consumption. The trade and consumption of bivalve shellfish is a global industry and is increasing. Human illness caused by infectious agents transmitted through animal or human sources through shellfish consumption has been recognized for many years. Safe Management of Shellfish and Harvest Waters addresses contaminant sources and means of transmission to bivalve shellfish and where possible, identifies options to interrupt the cycle. The efficacy of current practices is discussed with the aid of case studies written by practitioners working in the field from a number of developed and developing countries. The need for the deployment of new approaches to protect human health from infectious diseases associated with the consumption of contaminated bivalve shellfish is discussed, focusing specifically on water management aspects and strategies. Safe Management of Shellfish and Harvest Waters provides valuable information on the real health risks posed by shellfish consumption. It distills worldwide experience; identifies the challenges and opportunities that face the industry and suggests responses to those challenges. It provides the scientific basis for regulation and associated monitoring and risk reduction programmes to enable health agencies, water quality and shellfish regulatory agencies and other stakeholders worldwide to control and reduce the existing and potential future infectious disease problems through better management of shellfish waters. Safe Management of Shellfish and Harvest Waters will be invaluable for health agencies, water quality and shellfish regulatory agencies, and other environmental professionals working in the shellfish industry. Access the OECD area on the IWA WaterWiki here: http://www.iwawaterwiki.org/xwiki/bin/view/Articles/UsefulResourcesforDevelopingCountries_0

Comparison of Multiple Point and Composite Sampling for Monitoring Bathing Water Quality

Abstract The study was undertaken to assess the performance of a selected range of holiday destinations against the microbiological determinants of the European Union (EU) bathing water Directive [Council directive of 8 December 1975 concerning the quality of bathing waters. Official Journal L,31, 1–7. 76/160/EEC.]. The destinations were situated in three Mediterranean countries —Greece, Spain and Italy— and in the U.K. itself. The Mediterranean destinations were chosen on the basis of their popularity with British visitors, the U.K. beaches on a fairly random basis. All the beaches in all countries were EU designated bathing waters, several holding the prestigious European Blue Flag award. Summary findings indicate that the five beaches sampled in Spain were all of very good microbiological quality for the ten days of sampling. Four of the beaches examined in Crete were of similar good quality. The fifth, at Malia, was of much poorer quality. The five Italian beaches all failed at least one of the Mandatory standards for either total or thermotolerant (faecal) coliforms. All these failures occurred on the same two days, coincident with heavy rainfall. The six U.K. beaches surveyed all passed Mandatory standards for total coliforms but one beach did not comply with the Mandatory standard for thermotolerant coliforms. The fact that several of the Mediterranean and U.K. beaches examined in the study were European Blue Flag beaches and that, on occasion, their water quality failed to meet the criteria for that award, suggests that such award schemes should clearly indicate that the guarantee of bather safety is far from absolute.

Workgroup report : developing environmental health indicators for European children: World Health Organization Working Group

Abstract The United States Environmental Protection Agencys Beaches Environmental Assessment and Coastal Health Act (BEACH Act) requires states to develop monitoring and notification programs for recreational waters using approved bacterial indicators. Implementation of an appropriate monitoring program can, under some circumstances, be expensive. This study explored the use of composite sampling at two Racine, Wisconsin beaches over a four month period (n = 68 days) to determine whether compositing can provide a valid, unbiased, and cost-effective measure of water quality. Multiple point sampling occurred throughout the bathing season, with water samples collected daily from three or four fixed locations along each beach. From each individual sample, well-mixed aliquots were combined to form a composite sample. Individual and composite samples were assayed identically for Escherichia coli using Colilert-18 and Quanti-Tray 2000 (IDEXX Laboratories, Inc., Westbrook, ME). Results from this study indicate a reasonable expectation of a simple 1:1 ratio between the composite samples and the arithmetic mean of the individual samples. Additionally, log variance of the composite sample results did not differ significantly from that of the single sample averages (p > 0.2). Empirical values for log standard deviations varied by no more than 7% between the composite sample and individually assayed samples. Thus compositing, as performed in this study, appears to introduce neither significant bias nor additional variability into the monitoring results and stands as a reasonable alternative to data sets derived from single-sample methods. Regulatory programs adopting this approach could maintain sample integrity while reducing costs associated with recreational water quality assessment.

Use of IDEXX Colilert-18® and Quanti-Tray/2000 as a Rapid and Simple Enumeration Method for the Implementation of Recreational Water Monitoring and Notification Programs

A working group coordinated by the World Health Organization developed a set of indicators to protect children’s health from environmental risks and to support current and future European policy needs. On the basis of identified policy needs, the group developed a core set of 29 indicators for implementation plus an extended set of eight additional indicators for future development, focusing on exposure, health effects, and action. As far as possible, the indicators were designed to use existing information and are flexible enough to be developed further to meet the needs of policy makers and changing health priorities. These indicators cover most of the priority topic areas specified in the Children’s Environment and Health Action Plan for Europe (CEHAPE) as adopted in the Fourth Ministerial Conference on Health and Environment in 2004, and will be used to monitor the implementation of CEHAPE. This effort can be viewed as an integral part of the Global Initiative on Children’s Environmental Health Indicators, launched at the World Summit on Sustainable Development in 2002.

Workshop Report: Developing Pollution Source Tracking for Recreational and Shellfish Waters

Abstract The Beaches Environmental Assessment and Coastal Health Act of 2002 (BEACH Act) requires the implementation and/or expansion of routine recreational water quality monitoring programs in all United States coastal recreational waters, including the Great Lakes, to be adopted by 2004. While the standardization of sample collection and laboratory testing protocols is essential, the ability to provide timely public notification is an equally important element. In preparation for the implementation of the BEACH Act in Wisconsin the communities of Milwaukee and Racine investigated the use of IDEXX Colilert-18, Quanti-Tray/2000 (IDEXX) as a means to reduce the time necessary for public notification of recreational water quality while still providing accurate and consistent test results. Conducted over a 2-year period, this study compared two methods, IDEXX and an approved USEPA membrane filtration method (m-Tec agar), for the quantitative determination of Escherichia coli in split samples from fresh water beaches. ANOVA analysis of regression relation indicated no significant difference between the data sets obtained using these methodologies (p < 0.001). Parallel studies conducted in the United Kingdom produced similar results. The fact that IDEXX decreases the time from sample collection to public notification by over six hours coupled with its ease of use and consistent results make this method an attractive choice for the implementation of fresh water and marine beach management programs.