Residential buildings provide unique conditions for opportunistic premise plumbing pathogen (OPPP) exposure via aerosolized water droplets produced by showerheads, faucets, and tubs. The objective of this review was to critically evaluate the existing literature that assessed the impact of potentially enhancing conditions to OPPP occurrence associated with residential plumbing and to point out knowledge gaps. Comprehensive studies on the topic were found to be lacking. Major knowledge gaps identified include the assessment of OPPP growth in the residential plumbing, from building entry to fixtures, and evaluation of the extent of the impact of typical residential plumbing design (e.g., trunk and branch and manifold), components (e.g., valves and fixtures), water heater types and temperature setting of operation, and common pipe materials (copper, PEX, and PVC/CPVC). In addition, impacts of the current plumbing code requirements on OPPP responses have not been assessed by any study and a lack of guidelines for OPPP risk management in residences was identified. Finally, the research required to expand knowledge on OPPP amplification in residences was discussed.

Legionella is an opportunistic premise plumbing pathogen and causative agent of a severe pneumonia called Legionnaires\' Disease (LD). Cases of LD have been on the rise in the U.S. and globally. Although Legionella was first identified 45 years ago, it remains an \'emerging pathogen.\" Legionella is part of the normal ecology of a public water system and is frequently detected in regulatory-compliant drinking water. Drinking water utilities, regulators and public health alike are increasingly required to have a productive understanding of the evolving issues and complex discussions of the contribution of the public water utility to Legionella exposure and LD risk. This review provides a brief overview of scientific considerations important for understanding this complex topic, a review of findings from investigations of public water and LD, including data gaps, and recommendations for professionals interested in investigating public water utilities. Although the current literature is inconclusive in identifying a public water utility as a sole source of an LD outbreak, the evidence is clear that minimizing growth of Legionella in public water utilities through proper maintenance and sustained disinfectant residuals, throughout all sections of the water utility, will lead to a less conducive environment for growth of the bacteria in the system and the buildings they serve.

Opportunistic premise (i.e., building) plumbing pathogens (OPPPs, e.g., Legionella pneumophila, Mycobacterium avium complex, Pseudomonas aeruginosa, Acanthamoeba, and Naegleria fowleri) are a significant and growing source of disease. Because OPPPs establish and grow as part of the native drinking water microbiota, they do not correspond to fecal indicators, presenting a major challenge to standard drinking water monitoring practices. Further, different OPPPs present distinct requirements for sampling, preservation, and analysis, creating an impediment to their parallel detection. The aim of this critical review is to evaluate the state of the science of monitoring OPPPs and identify a path forward for their parallel detection and quantification in a manner commensurate with the need for reliable data that is informative to risk assessment and mitigation. Water and biofilm sampling procedures, as well as factors influencing sample representativeness and detection sensitivity, are critically evaluated with respect to the five representative bacterial and amoebal OPPPs noted above. Available culturing and molecular approaches are discussed in terms of their advantages, limitations, and applicability. Knowledge gaps and research needs towards standardized approaches are identified.

The problems related to hydrogen sulfide in terms of deterioration of sewer networks, toxicity and odor nuisance have become very clear to the network stakeholders and the public. The hydraulic and (bio)chemical phenomena and parameters controlling sulfide formation, emission and their incidences in sewer networks are very complex. Recent research studies have been developed in gravity and pressure sewers and some transfer models have been published. Nevertheless, the models do not take into account all the physical phenomena influencing the emission process. After summing up the main scientific knowledge concerning the production, oxidation, transfer and emission processes, the present review includes: (i) a synthetic analysis of sulfide and hydrogen sulfide emission models in sewer networks, (ii) an estimation of their limit, (iii) perspectives to improve the modelling approach. It shows that sulfide formation and uptake models still need refinements especially for some phenomena such as liquid to gas mass transfer. Transfer models that have been published so far are purposely simplified and valid for simple systems. More efforts have to be undertaken in order to better understand the mechanisms and the dynamics of hydrogen sulfide production and emission in real conditions.

OBJECTIVE: To synthesise and evaluate the evidence of the effectiveness of interventions to prevent scalds in children.
METHODS: An overview of systematic reviews (SR) and a SR of primary studies were performed evaluating interventions to prevent scalds in children. A comprehensive literature search was conducted covering various resources up to October 2012. Experimental and controlled observational studies reporting scald injuries, safety practices and safety equipment use were included.
RESULTS: Fourteen systematic reviews and 39 primary studies were included. There is little evidence that interventions are effective in reducing the incidence of scalds in children. More evidence was found that inventions are effective in promoting safe hot tap water temperature, especially when home safety education, home safety checks and discounted or free safety equipment including thermometers and thermostatic mixing valves were provided. No consistent evidence was found for the effectiveness of interventions on the safe handling of hot food or drinks nor improving kitchen safety practices.
CONCLUSIONS: Education, home safety checks along with thermometers or thermostatic mixing valves should be promoted to reduce tap water scalds. Further research is needed to evaluate the effectiveness of interventions on scald injuries and to disentangle the effects of multifaceted interventions on scald injuries and safety practices.

Opportunistic pathogens occurring in premise (i.e., building) plumbing systems, including strains of Legionella, Mycobacterium, Acanthamoeba, and Pseudomonas, are now frequently cited agents of waterborne disease outbreaks. Unlike traditional fecal pathogens, opportunistic pathogens are part of the drinking water microbial ecology and therefore require new paradigms for their control. With the onset of the \"microbiome era\", notions of eradicating all microbes in drinking water have proven unrealistic, making a probiotic concept worthy of consideration. Research is needed to better understand how engineering controls may individually, or in combination, select for a desirable microbiome, and how the microbiome itself may mediate proliferation of opportunistic pathogens. Ecological interactions such as competition, antagonism, and obligate parasite-host relationships offer potential targets for probiotic control of opportunistic pathogens. A probiotic approach may be defined as intentional inoculation of beneficial microbes or choosing conditions that select for a desirable microbiome. This critical review synthesizes the state of the knowledge of the factors governing opportunistic pathogen control in premise plumbing and potential opportunities for and barriers to implementation of a probiotic approach. Future effort is recommended to demonstrate the feasibility of the probiotic concept; to develop effective, practical, and safe protocols; and to engage relevant stakeholders in evaluating options and assessing corresponding risks.

Several bacterial species that are natural inhabitants of potable water distribution system biofilms are opportunistic pathogens important to sensitive patients in healthcare facilities. Waterborne healthcare-associated infections (HAI) may occur during the many uses of potable water in the healthcare environment. Prevention of infection is made more challenging by lack of data on infection rate and gaps in understanding of the ecology, virulence, and infectious dose of these opportunistic pathogens. Some healthcare facilities have been successful in reducing infections by following current water safety guidelines. This review describes several infections, and remediation steps that have been implemented to reduce waterborne HAIs.

The critical importance of unrestricted access to clean drinking water and basic sanitation for all is highlighted in Millennium Development Goal 7, which calls for the reduction by half of the proportion of people without such access by 2015. Unfortunately, little attention has been paid to the needs of such access for the one billion people living with a disability worldwide, despite the fact that the right to equal access for all international development initiatives is guaranteed in the new United Nations Convention on the Rights of Persons with Disabilities. In this paper, we review what is currently known about access to water and sanitation for persons with disabilities in low- and middle-income countries from the perspective of both international development and global health, and identify existing gaps in research, practice and policy that are of pressing concern if the water and sanitation needs of this large - and largely overlooked - population are to be addressed.

Like most cities in developing countries, Uganda\'s capital city, Kampala, is experiencing urbanisation leading to an increase in population, and rapid development of peri-urban (informal) settlements. More than 60% of the city\'s population resides in these settlements which have the lowest basic service levels (sanitation, water supply, solid waste collection, stormwater and greywater disposal). A review of earlier studies on infrastructure development and sustainability within Kampala\'s peri-urban settlements, field surveys in a typical peri-urban settlement in the city (Bwaise III Parish), and structured interviews with key personnel from the National Water and Sewerage Corporation (NWSC), Kampala City Council (KCC), and the National Environment Management Authority (NEMA) were undertaken. Findings on current environmental health practices as well as perspectives of local communities and interviewed institutions on problems, constraints and possible solutions to basic service provision are presented. The implications of these viewpoints for possible environmental health interventions are presented.

Introduction, consolidation and even standardization of expensive conventional aerobic systems for domestic wastewater treatment imposed significant financial constraints on the expansion of sanitary services including treatment in developing countries. A viable alternative is the sequential anaerobic-aerobic systems. If compared with the conventional aerobic technologies based on activated sludge processes, lower energy consumption and lower excess sludge production can be achieved with a high-rate anaerobic pre-treatment step. Particularly with concentrated sewage, the energy benefit of applying anaerobic pre-treatment will become very significant. This study aims on putting the effectiveness of sequential systems for treatment of domestic wastewater on view, through displaying results presented in literature on the performance of these systems.