scholarly journals A systematic review of waterborne disease burden methodologies from developed countries

2014 ◽  
Vol 12 (4) ◽  
pp. 634-655 ◽  
Author(s):  
H. M. Murphy ◽  
K. D. M. Pintar ◽  
E. A. McBean ◽  
M. K. Thomas

The true incidence of endemic acute gastrointestinal illness (AGI) attributable to drinking water in Canada is unknown. Using a systematic review framework, the literature was evaluated to identify methods used to attribute AGI to drinking water. Several strategies have been suggested or applied to quantify AGI attributable to drinking water at a national level. These vary from simple point estimates, to quantitative microbial risk assessment, to Monte Carlo simulations, which rely on assumptions and epidemiological data from the literature. Using two methods proposed by researchers in the USA, this paper compares the current approaches and key assumptions. Knowledge gaps are identified to inform future waterborne disease attribution estimates. To improve future estimates, there is a need for robust epidemiological studies that quantify the health risks associated with small, private water systems, groundwater systems and the influence of distribution system intrusions on risk. Quantification of the occurrence of enteric pathogens in water supplies, particularly for groundwater, is needed. In addition, there are unanswered questions regarding the susceptibility of vulnerable sub-populations to these pathogens and the influence of extreme weather events (precipitation) on AGI-related health risks. National centralized data to quantify the proportions of the population served by different water sources, by treatment level, source water quality, and the condition of the distribution system infrastructure, are needed.

2017 ◽  
Vol 15 (4) ◽  
pp. 475-489 ◽  
Author(s):  
S. Coly ◽  
N. Vincent ◽  
E. Vaissiere ◽  
M. Charras-Garrido ◽  
A. Gallay ◽  
...  

Hundreds of waterborne disease outbreaks (WBDO) of acute gastroenteritis (AGI) due to contaminated tap water are reported in developed countries each year. Such outbreaks are probably under-detected. The aim of our study was to develop an integrated approach to detect and study clusters of AGI in geographical areas with homogeneous exposure to drinking water. Data for the number of AGI cases are available at the municipality level while exposure to tap water depends on drinking water networks (DWN). These two geographical units do not systematically overlap. This study proposed to develop an algorithm which would match the most relevant grouping of municipalities with a specific DWN, in order that tap water exposure can be taken into account when investigating future disease outbreaks. A space-time detection method was applied to the grouping of municipalities. Seven hundred and fourteen new geographical areas (groupings of municipalities) were obtained compared with the 1,310 municipalities and the 1,706 DWN. Eleven potential WBDO were identified in these groupings of municipalities. For ten of them, additional environmental investigations identified at least one event that could have caused microbiological contamination of DWN in the days previous to the occurrence of a reported WBDO.


2019 ◽  
Vol 17 (6) ◽  
pp. 845-862 ◽  
Author(s):  
M. H. Akuno ◽  
G. Nocella ◽  
E. P. Milia ◽  
L. Gutierrez

Abstract The relationship between naturally fluoridated groundwater and dental fluorosis has received large attention from researchers around the world. Despite recognition that several factors influence this relationship, there is a lack of systematic studies analyzing the heterogeneity of these results. To fill such a gap, this study performs a systematic review and meta-analysis to understand which factors influence this relationship and how. Selected studies were sampled between 2007 and 2017 from Web of Science, PubMed, Google Scholar and Scopus using keywords and Boolean operators. Results of the systematic review show that dental fluorosis affects individuals of all ages, with the highest prevalence below 11, while the impact of other factors (gender, environmental conditions, diet and dental caries) was inconclusive. Meta-regression analysis, based on information collected through systematic review, indicates that both fluoride in drinking water and temperature influence dental fluorosis significantly and that these studies might be affected by publication bias. Findings show that fluoride negatively affects people's health in less developed countries. The conclusions discuss policy tools and technological innovations that could reduce fluoride levels below that of the World Health Organization (WHO) (<1.5 mg/L).


PLoS ONE ◽  
2015 ◽  
Vol 10 (10) ◽  
pp. e0141646 ◽  
Author(s):  
Wendy Pons ◽  
Ian Young ◽  
Jenifer Truong ◽  
Andria Jones-Bitton ◽  
Scott McEwen ◽  
...  

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Nusa Idaman Said

Water disinfection means the removal, deactivation or killing of pathogenic microorganisms. Microorganisms are destroyed or deactivated, resulting in termination of growth and reproduction. When microorganisms are not removed from drinking water, drinking water usage will cause people to fall ill. Chemical inactivation of microbiological contamination in natural or untreated water is usually one of the final steps to reduce pathogenic microorganisms in drinking water. Combinations of water purification steps (oxidation, coagulation, settling, disinfection, and filtration) cause (drinking) water to be safe after production. As an extra measure many countries apply a second disinfection step at the end of the water purification process, in order to protect the water from microbiological contamination in the water distribution system. Usually one uses a different kind of disinfectant from the one earlier in the process, during this disinfection process. The secondary disinfection makes sure that bacteria will not multiply in the water during distribution. This paper describes several technique of disinfection process for drinking water treatment. Disinfection can be attained by means of physical or chemical disinfectants. The agents also remove organic contaminants from water, which serve as nutrients or shelters for microorganisms. Disinfectants should not only kill microorganisms. Disinfectants must also have a residual effect, which means that they remain active in the water after disinfection. For chemical disinfection of water the following disinfectants can be used such as Chlorine (Cl2),  Hypo chlorite (OCl-), Chloramines, Chlorine dioxide (ClO2), Ozone (O3), Hydrogen peroxide etch. For physical disinfection of water the following disinfectants can be used is Ultraviolet light (UV). Every technique has its specific advantages and and disadvantages its own application area sucs as environmentally friendly, disinfection byproducts, effectivity, investment, operational costs etc. Kata Kunci : Disinfeksi, bakteria, virus, air minum, khlor, hip khlorit, khloramine, khlor dioksida, ozon, UV.


2002 ◽  
Vol 2 (1) ◽  
pp. 319-324
Author(s):  
M.M. Critchley ◽  
N.J. Cromar ◽  
N. McClure ◽  
H.J. Fallowfield

This study investigated the potential for distribution system biofilm bacteria to elevate copper concentrations in drinking water. Biofilms were sampled from household copper reticulation pipes and grown on R2A agar. Laboratory coupon experiments were used to determine the effect of single isolate biofilms on aqueous copper concentrations. The majority of biofilm bacteria did not affect copper concentrations in comparison to sterile controls. However, several bacteria including Acidovorax delafieldii, Cytophaga johnsonae and Micrococcus kristinae were shown to significantly elevate copper concentrations in drinking water. In contrast, the bacteria Rhodococcus sp. and Xanthomonas maltophilia were shown to significantly decrease copper levels in comparison to controls. The significance of biofilm bacteria to increase copper concentrations in drinking water has implications for public health by increasing concentrations to levels toxic to humans.


2008 ◽  
Vol 8 (4) ◽  
pp. 421-426
Author(s):  
J. Menaia ◽  
M. Benoliel ◽  
A. Lopes ◽  
C. Neto ◽  
E. Ferreira ◽  
...  

Concerns arise from the possible occurrence of pathogens in drinking water pipe biofilms and storage tank sediments. In these studies, biofilm samples from pipes and sediments from storage tanks of the Lisbon drinking water distribution system were analyzed. Protein determinations and heterotrophic counts on pipe biofilm samples were used to assess the Lisbon network sessile colonization intensity and distribution. Indicator and pathogenic microorganisms were analyzed in pipe biofilm samples, as well as in storage tanks biofilm and sediments, by using cultural methods and PCR, to assess risks. Results have shown that the Lisbon network sessile colonization is relatively weak in intensity. In addition, no meaningful hazards were apparent for both the network biofilm and the storage tanks biofilm and sediments.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Ariadna Huertas-Zurriaga ◽  
Patrick A. Palmieri ◽  
Joan E. Edwards ◽  
Sandra K. Cesario ◽  
Sergio Alonso-Fernandez ◽  
...  

Abstract Background Women living with HIV (WLH) lack evidence-based information about reproductive options while managing pressures from family, clinicians, and communities to give up the idea of having children. As the reproduction intentions of WLH are not well understood, stigmatizing behaviors force them to hide their disease to avoid rejection by their family, partner, and social networks. Compliance with social norms, fear of stigma, and discrimination influence their experience. Current research is individual qualitative studies lacking the synthesis perspective necessary to guide intervention development. The purpose of this study was to synthesize the evidence to explain the reproductive decision-making process for WLH in developed countries. Methods A systematic review with qualitative research synthesis was conducted through searches in 10 electronic databases (CINAHL, EMBASE, MEDLINE, Scopus, Social Science Citation Index, Web of Science, Google Scholar, Cuidatge, Cuiden Enfispo, and SciELO). Studies published in journals from 1995 to 2019 with qualitative data about reproductive decision-making among WLH in developed countries were eligible for inclusion. Developed country was operationalized by membership in the OECD for comparative conditions of social wellbeing and economic stability. The CASP and JBI checklists for qualitative research were used to assess study quality and methodological integrity. Thematic analysis and qualitative meta-summary techniques were used for the synthesis. Results Twenty studies from 12 developed countries were included in the synthesis. Findings were organized into 3 meta-themes from 15 themes and 45 subthemes, including: (1) Shattered identity, (2) Barriers, inequities, and misinformation, (3) Coping, resiliency, and support. Reproductive decision-making was perceived as a complex process influenced by facilitators and barriers. The facilitators helped WLH cope with their new situation to become more resilient, while the barriers made their situation more difficult to manage. Conclusion WLH encounter reproductive decision-making with knowledge deficits and limited social support. An integrated approach to holistic care with comprehensive multidisciplinary counseling is needed to support WLH. Clinicians could benefit from professional development to learn how to be authentically present for WLH, including engaging in conversations, demonstrating compassion, and understanding situations. Evidence-based clinical practice guidelines need to be tailored for the family planning and sexual health needs of WLH.


Author(s):  
Réka Vágvölgyi ◽  
Kirstin Bergström ◽  
Aleksandar Bulajić ◽  
Maria Klatte ◽  
Tânia Fernandes ◽  
...  

AbstractA considerable amount of the population in more economically developed countries are functionally illiterate (i.e., low literate). Despite some years of schooling and basic reading skills, these individuals cannot properly read and write and, as a consequence have problems to understand even short texts. An often-discussed approach (Greenberg et al. 1997) assumes weak phonological processing skills coupled with untreated developmental dyslexia as possible causes of functional illiteracy. Although there is some data suggesting commonalities between low literacy and developmental dyslexia, it is still not clear, whether these reflect shared consequences (i.e., cognitive and behavioral profile) or shared causes. The present systematic review aims at exploring the similarities and differences identified in empirical studies investigating both functional illiterate and developmental dyslexic samples. Nine electronic databases were searched in order to identify all quantitative studies published in English or German. Although a broad search strategy and few limitations were applied, only 5 studies have been identified adequate from the resulting 9269 references. The results point to the lack of studies directly comparing functional illiterate with developmental dyslexic samples. Moreover, a huge variance has been identified between the studies in how they approached the concept of functional illiteracy, particularly when it came to critical categories such the applied definition, terminology, criteria for inclusion in the sample, research focus, and outcome measures. The available data highlight the need for more direct comparisons in order to understand what extent functional illiteracy and dyslexia share common characteristics.


Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4133
Author(s):  
Alessandro Bosisio ◽  
Matteo Moncecchi ◽  
Andrea Morotti ◽  
Marco Merlo

Currently, distribution system operators (DSOs) are asked to operate distribution grids, managing the rise of the distributed generators (DGs), the rise of the load correlated to heat pump and e-mobility, etc. Nevertheless, they are asked to minimize investments in new sensors and telecommunication links and, consequently, several nodes of the grid are still not monitored and tele-controlled. At the same time, DSOs are asked to improve the network’s resilience, looking for a reduction in the frequency and impact of power outages caused by extreme weather events. The paper presents a machine learning GIS-based approach to estimate a secondary substation’s load profiles, even in those cases where monitoring sensors are not deployed. For this purpose, a large amount of data from different sources has been collected and integrated to describe secondary substation load profiles adequately. Based on real measurements of some secondary substations (medium-voltage to low-voltage interface) given by Unareti, the DSO of Milan, and georeferenced data gathered from open-source databases, unknown secondary substations load profiles are estimated. Three types of machine learning algorithms, regression tree, boosting, and random forest, as well as geographic information system (GIS) information, such as secondary substation locations, building area, types of occupants, etc., are considered to find the most effective approach.


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