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Legge H, Kazungo K, Muli S, Elson L, Mwongeli J, Halliday KE, Ochwal V, Oswald W, Dreibelbis R, Njomo D, Mwandawiro C, Fillinger U, Pullan R, Kepha S. Identifying Potential Determinants of Faecal Contamination on Domestic Floors in Three Settings in Rural Kenya: A Mixed Methods Analysis. ENVIRONMENTAL HEALTH INSIGHTS 2024; 18:11786302241246454. [PMID: 38737960 PMCID: PMC11088304 DOI: 10.1177/11786302241246454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 03/21/2024] [Indexed: 05/14/2024]
Abstract
Observational evidence suggests that household floors may be an important domain for the transmission of enteric and parasitic infections. However, little work has been done to investigate how household floors can become contaminated with human and animal faeces. This study uses a mixed methods approach to postulate the proximal and distal determinants of household floor contamination with faeces in groups of rural villages in 3 counties in Kenya (Bungoma, Kwale and Narok). Quantitative data was collected through a household census and analysed descriptively and using mixed effects logistic regression models. Qualitative data was collected through unstructured observations of daily routines and in-depth interviews. These data were analysed thematically with case memos produced for routine activities that were hypothesised to be determinants of floor contamination. Possible proximal determinants of floor contamination included; (1) animal contact with floors; (2) child faeces disposal, and; (3) floor cleaning routines. Distal determinants are suggested to be rooted in the socioeconomic, environmental, and cultural context in which households were located and included; (1) the type and number of animals owned by households; (2) presence/absence of dedicated shelters for housing animals at night, which impacted whether sleeping or cooking areas were exposed to animals; (3) Accessibility of inside spaces to poultry and other roaming animals; (4) ownership of an improved floor; (5) ability of animals to access neighbours compounds; (6) seasonal changes in weather. These results will be of use in identifying the contexts in which faecal contamination of domestic floors may be contributing towards transmission of enteric and parasitic infections and in designing effective interventions to prevent this exposure.
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Affiliation(s)
- Hugo Legge
- London School of Hygiene & Tropical Medicine, UK
| | - Karisa Kazungo
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Sharon Muli
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Lynne Elson
- KEMRI-Wellcome Trust, Nairobi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, UK
| | - Jacinta Mwongeli
- Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | | | - Victoria Ochwal
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - William Oswald
- London School of Hygiene & Tropical Medicine, UK
- Global Health Division, International Development Group, RTI International, Research Triangle Park, NC, USA
| | | | - Doris Njomo
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Charles Mwandawiro
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Ulrike Fillinger
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | | | - Stella Kepha
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
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Gizaw Z, Yalew AW, Bitew BD, Lee J, Bisesi M. Animal Handling Practice Among Rural Households in Northwest Ethiopia Increases the Risk of Childhood Diarrhea and Exposure to Pathogens From Animal Sources. ENVIRONMENTAL HEALTH INSIGHTS 2024; 18:11786302241245057. [PMID: 38596430 PMCID: PMC11003343 DOI: 10.1177/11786302241245057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024]
Abstract
Background In Ethiopia, domestic animals and their feces are not properly contained. However, the risk of exposure to zoonotic pathogens is not well documented. This study was conducted to assess animal handling practices and the risk of childhood diarrhea among rural households in northwest Ethiopia. Methods This study was done among 403 randomly selected households. Information on animal handling was collected using a questionnaire and spot-check observation. The occurrence of childhood diarrhea in 14 days prior to the survey was assessed based on the reports of female head of households. Multivariable binary logistic regression analysis was performed to identify the association between animal handling practices and childhood diarrhea. Results All the female head of households had contact with animal feces when preparing fuel disks and plastering the house components with animal dung. Domestic animals shared a corral within the living space of the humans in 20% of the households. Animals entered the human living quarters and accessed foods in 32% of the households. Moreover, 24% of the children aged 24 to 59 months had diarrhea in a 2-week period prior to the survey. Childhood diarrhea was associated with domestic animals sharing the same house as humans (AOR: 3.3, 95% CI: 1.3, 8.6), presence of animal excreta in child playing areas (AOR: 2.4, 95% CI: 1.2, 4.6), contact of domestic animals with stored foods (AOR: 3.5, 95% CI: 2.0, 5.9), trapped dirt under fingernails of female heads (AOR: 3.7, 95% CI: 1.9, 7.5), open defecation (AOR: 3.24, 95% CI: 1.8, 5.9), and unprotected sources (AOR: 4.2, 95% CI: 1.1, 15.3). Conclusion Domestic animals and their excreta are not hygienically contained in the area. Animal handling practices including their excreta and the hygiene behavior of female head of households (eg, handwashing and food handling practices) should be improved to prevent childhood diarrhea.
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Affiliation(s)
- Zemichael Gizaw
- Department of Environmental and Occupational Health and Safety, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
- Global One Health Initiative (GOHi), the Ohio State University, Columbus, OH, USA
| | | | - Bikes Destaw Bitew
- Department of Environmental and Occupational Health and Safety, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Jiyoung Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, USA
- Department of Food Science and Technology, the Ohio State University, Columbus, OH, USA
| | - Michael Bisesi
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, USA
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Barasa E, Indieka B, Shaviya N, Osoro E, Maloba G, Mukhongo D, Budambula V, Were T. Assemblages and Subassemblages of Giardia duodenalis in Rural Western, Kenya: Association with Sources, Signs, and Symptoms. J Parasitol Res 2024; 2024:1180217. [PMID: 38348444 PMCID: PMC10861282 DOI: 10.1155/2024/1180217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 01/02/2024] [Accepted: 01/16/2024] [Indexed: 02/15/2024] Open
Abstract
Background Giardia duodenalis causes sporadic or epidemic infections in humans. The parasite comprises assemblages A-H with A and B subdivided further into AI-IV and BI-IV subassemblages. Attempts aimed at linking these genotypes with sources and gastrointestinal manifestations of the infection are largely unexplored in rural communities. Methods In this cross-sectional study, G. duodenalis infection was genotyped and associated with sources, and gastrointestinal signs and symptoms of the disease among residents of Busia County, a rural setting in western Kenya. Demographic and clinical information were captured using standardized forms. Stool specimens were obtained from the patients and used for genotyping at glutamate dehydrogenase and triose-phosphate isomerase loci using the polymerase chain reaction and restriction fragment length polymorphism. Results Assemblage B (63.6%) was the most prevalent G. duodenalis infection, while A (20.5%) and mixed A/B (15.9%) were also detected. Among the subassemblages, AI (5.7%), AII (8.0%), AIII (3.4), BIII (30.7%), and BIV (17.0%) were diagnosed including the mixed AII/BIII (15.9%), BIII/BIV (15.9%), AI/AIII (2.3%), and AI/AII (1.1%) infections. Binary logistic regression indicated associations for assemblage A with stomach upset, history of nitroimidazole treatment, and residing in a homestead with cattle and B with age < 18 years, history of eating outdoors, vomiting, steatorrhea, and residing in a homestead with cattle, goats, and poultry (p < 0.05 for all). Among the subassemblages, associations were found for AI with residing in a homestead having cattle and history of nitroimidazole treatment, BIII with residing in a homestead having cattle and poultry, and BIV with steatorrhea (p < 0.05 for all). Altogether, this study illustrates that G. duodenalis assemblage B and subassemblage BIII are the most predominant and are linked to age < 18 years, gastrointestinal manifestations, and living in a homestead with domestic ruminants and poultry. Conclusion Targeted mass prophylactic treatment of domestic animals and utilization of gastrointestinal presentations, age < 18 years, and a history of nitroimidazole use are useful in the diagnosis and prevention of giardiasis among residents of rural communities.
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Affiliation(s)
- Erick Barasa
- Department of Medical Laboratory Sciences, Masinde Muliro University of Science and Technology, P. O. Box 190-50100, Kakamega, Kenya
| | - Briston Indieka
- Department of Biomedical Science and Technology, Maseno University, Postal address, Private Bag Maseno, Kenya
| | - Nathan Shaviya
- Department of Medical Laboratory Sciences, Masinde Muliro University of Science and Technology, P. O. Box 190-50100, Kakamega, Kenya
| | - Ezra Osoro
- Department of Medical Biochemistry, Masinde Muliro University of Science and Technology, P. O. Box 190-50100, Kakamega, Kenya
| | - Geofrey Maloba
- Department of Medical Biochemistry, Masinde Muliro University of Science and Technology, P. O. Box 190-50100, Kakamega, Kenya
| | - Denis Mukhongo
- Department of Biological Sciences, Alupe University, P. O. Box 845-50400, Busia, Kenya
| | - Valentine Budambula
- Department of Environment and Health, Technical University of Mombasa, Mombasa, Kenya
| | - Tom Were
- Department of Laboratory Medicine and Human Pathology, Masinde Muliro University of Science and Technology, Kakamega, Kenya
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Viana E, França Y, de Azevedo LS, Medeiros RS, Guiducci R, Guadagnucci S, Luchs A. Genotypic diversity and long-term impact of human bocavirus on diarrheal disease: Insights from historical fecal samples in Brazil. J Med Virol 2024; 96:e29429. [PMID: 38258346 DOI: 10.1002/jmv.29429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/11/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024]
Abstract
This study aimed to investigate the frequency and genotypic diversity of human bocavirus (HBoV) in historical fecal samples collected before 2005 in Brazil and understand its natural history in patients with diarrhea. Between 1998 and 2005, 3347 samples were tested for HBoV by RT-PCR, with a detection rate of 5.8% (195/3347). Coinfection with norovirus (NoV) and human adenovirus (HAdV) was found in 34.9% (68/195), indicating HBoV's potential role as a causative agent of diarrheal disease. The detection rate varied over the years (p < 0.05), suggesting natural oscillatory fluctuations. HBoV was more prevalent in fall and winter, with higher positivity in children ≤5 years (p < 0.05), reinforcing that HBoV is an important pathogen in childhood diarrhea. Genotyping (32.8%; 64/195) revealed the circulation of HBoV-1 (79.7%, 51/64), HBoV-3 (12.5%, 8/64), HBoV-2 (6.2%, 4/64), and the rare HBoV-4 (1.6%, 1/64). Difference in HBoV-1 and HBoV-2/-3 mono-infections prevalence (p < 0.05), suggests a potential role of HBoV-1 in the pathogenicity of diarrheal disease. The study highlights HBoV's lasting impact on viral gastroenteritis in Brazil and emphasizes its genotypic diversity. Recommending screening for HBoV in public health laboratories is crucial for understanding its role in gastrointestinal diseases. The data also contribute to understanding the molecular characterization of enteric viruses in historical fecal samples.
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Affiliation(s)
- Ellen Viana
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Yasmin França
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Lais S de Azevedo
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Roberta S Medeiros
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Raquel Guiducci
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Simone Guadagnucci
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Adriana Luchs
- Enteric Disease Laboratory, Virology Center, Adolfo Lutz Institute, Sao Paulo, Brazil
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Baker KK, Simiyu S, Busienei P, Gutema FD, Okoth B, Agira J, Amondi CS, Ziraba A, Kapanka AG, Osinuga A, Ouma C, Sewell DK, Gaire S, Tumwebaze IK, Mberu B. Protocol for the PATHOME study: a cohort study on urban societal development and the ecology of enteric disease transmission among infants, domestic animals and the environment. BMJ Open 2023; 13:e076067. [PMID: 38000826 PMCID: PMC10680014 DOI: 10.1136/bmjopen-2023-076067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 10/25/2023] [Indexed: 11/26/2023] Open
Abstract
INTRODUCTION Global morbidity from enteric infections and diarrhoea remains high in children in low-income and middle-income countries, despite significant investment over recent decades in health systems and water and sanitation infrastructure. Other types of societal development may be required to reduce disease burden. Ecological research on the influence of household and neighbourhood societal development on pathogen transmission dynamics between humans, animals and the environment could identify more effective strategies for preventing enteric infections. METHODS AND ANALYSIS The 'enteric pathome'-that is, the communities of viral, bacterial and parasitic pathogens transmitted from human and animal faeces through the environment is taxonomically complex in high burden settings. This integrated cohort-exposure assessment study leverages natural socioeconomic spectrums of development to study how pathome complexity is influenced by household and neighbourhood infrastructure and hygiene conditions. We are enrolling under 12-month-old children in low-income and middle-income neighbourhoods of two Kenyan cities (Nairobi and Kisumu) into a 'short-cohort' study involving repeat testing of child faeces for enteric pathogens. A mid-study exposure assessment documenting infrastructural, behavioural, spatial, climate, environmental and zoonotic factors characterises pathogen exposure pathways in household and neighbourhood settings. These data will be used to inform and validate statistical and agent-based models (ABM) that identify individual or combined intervention strategies for reducing multipathogen transmission between humans, animals and environment in urban Kenya. ETHICS AND DISSEMINATION The protocols for human subjects' research were approved by Institutional Review Boards at the University of Iowa (ID-202004606) and AMREF Health Africa (ID-ESRC P887/2020), and a national permit was obtained from the Kenya National Commission for Science Technology and Innovation (ID# P/21/8441). The study was registered on Clinicaltrials.gov (Identifier: NCT05322655) and is in pre-results stage. Protocols for research on animals were approved by the University of Iowa Animal Care and Use Committee (ID 0042302).
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Affiliation(s)
- Kelly K Baker
- Department of Occupational and Environmental Health, The University of Iowa College of Public Health, Iowa City, Iowa, USA
| | - Sheillah Simiyu
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
| | - Phylis Busienei
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
| | - Fanta D Gutema
- Department of Occupational and Environmental Health, The University of Iowa College of Public Health, Iowa City, Iowa, USA
| | - Bonphace Okoth
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
| | - John Agira
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
| | - Christine S Amondi
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
| | - Abdhalah Ziraba
- Division of Health and Wellbeing, African Population and Health Research Center, Nairobi, Kenya
| | - Alexis G Kapanka
- Department of Occupational and Environmental Health, The University of Iowa College of Public Health, Iowa City, Iowa, USA
| | - Abisola Osinuga
- Department of Occupational and Environmental Health, The University of Iowa College of Public Health, Iowa City, Iowa, USA
- The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | | | - Daniel K Sewell
- Department of Biostatistics, The University of Iowa College of Public Health, Iowa City, Iowa, USA
| | - Sabin Gaire
- Department of Biostatistics, The University of Iowa College of Public Health, Iowa City, Iowa, USA
| | - Innocent K Tumwebaze
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
| | - Blessing Mberu
- Division of Population Dynamics and Urbanization, African Population and Health Research Center, Nairobi, Kenya
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Mohammadi M, Jafari H, Etemadi M, Dalugoda Y, Mohtady Ali H, Phung H, Ahmadvand A, Dwirahmadi F, Barnes P, Chu C. Health Problems of Increasing Man-Made and Climate-Related Disasters on Forcibly Displaced populations: A Scoping Review on Global Evidence. Disaster Med Public Health Prep 2023; 17:e537. [PMID: 37994107 DOI: 10.1017/dmp.2023.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
Forcibly displaced populations are among the most vulnerable groups in disasters. They experience poorer health conditions compared with nondisplaced individuals. However, a clear picture is lacking regarding the overall health problems encountered by disaster-induced mid- to long-term displaced people. This study investigated these disorders prevalence and identified their correlates among long-settled displaced populations worldwide. The current scoping review follows the PRISMA-ScR guidelines; a systematic search was conducted on PubMed, Web of Science, and CINAHL and included original peer-reviewed studies, commentary, reviews, and grey literature published in English between January 1990 to June 2022. In the thematic and content analysis, the authors applied the narrative review approach to identify themes and sub-themes. Forty-eight documents were identified as fully relevant to this study. The largest number of published papers were from Asia, followed by the Middle East, the United States, and Europe. IDPs in developed countries were the most researched populations. Human-made disasters were addressed by 89% of the included studies. The four main thematic categories included were "physical health," "mental health," "inadequate facilities," and "lack of healthy behaviour." The worsening of noncommunicable diseases had the highest prevalence, followed by communicable diseases. Due to their condition, forcibly displaced migrants face a triple burden of communicable diseases and noncommunicable diseases such as mental health issues. Health-related research and policy need to consider the links among disasters, health problems, and forced migration as a determinant of health in the new era of climate change-driven displacements.
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Affiliation(s)
- Mahan Mohammadi
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD 4222, Australia
| | - Hamid Jafari
- Department of Medical Emergencies, School of Medical Sciences, Sirjan, Iran
- Health in Disasters and Emergencies Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran
| | - Manal Etemadi
- The National Institute for Health and Care Research Applied Research Collaboration West (NIHR ARC West) at University Hospitals Bristol and Weston NHS Foundation Trust, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, UK
| | - Yohani Dalugoda
- School of Public Health, The University of Queensland, Herston, QLD 4006, Australia
| | - Heba Mohtady Ali
- Cities Research Institute & School of Engineering and Built Environment, Griffith University, Gold Coast, Australia
| | - Hai Phung
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD 4222, Australia
| | - Alireza Ahmadvand
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD 4222, Australia
| | - Febi Dwirahmadi
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD 4222, Australia
| | - Paul Barnes
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD 4222, Australia
| | - Cordia Chu
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD 4222, Australia
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Belina D, Gobena T, Kebede A, Chimdessa M, Hailu Y, Hald T. Occurrence of Diarrheagenic Pathogens and Their Coinfection Profiles in Diarrheic Under Five Children and Tracked Human Contacts in Urban and Rural Settings of Eastern Ethiopia. Microbiol Insights 2023; 16:11786361231196527. [PMID: 37736061 PMCID: PMC10510352 DOI: 10.1177/11786361231196527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Accepted: 06/27/2023] [Indexed: 09/23/2023] Open
Abstract
Diarrheagenic Escherichia coli, Campylobacter, Nontyphoidal Salmonella, and Shigella are common cause of childhood diarrhea in countries like Ethiopia, but data on their sources and coinfection profiles is limited. A cross sectional study was conducted from November 2021 to January 2023 to determine the prevalence, coinfection, and monthly occurrence rates of major diarrheagenic bacteria in diarrheic under five children and asymptomatic contacts at urban and rural settings in Ethiopia. A total of 345 stool samples were collected from; 262 diarrheic children visiting Hiwot Fana Hospital, Kersa, and Adelle Health Centers; and 83 caretakers and siblings through case based contact tracing. Samples were analyzed using standard laboratory procedures and the overall prevalence of enteric pathogens was 26.96%, with the highest isolation rate during the winter and peaks of 73.91% in February. The occurrence of the pathogens in children and tracked contacts was 27.86 and 24.09%, respectively. In our study, 8.53% coinfection and 23.66% single pathogen infection was recorded in diarrheic children. The study also showed 4.51 and 3.88% of diarrhea in children from urban and rural had attributed to bacterial coinfection, respectively. The most prevalent pathogen in diarrheic children was Diarrheagenic E. coli (10.31%), and followed by Campylobacter. On the other hand, Diarrheagenic E. coli was the second dominant bacteria following Shigella in the traced contacts, with prevalence of 8.43% and 9.64%, respectively. Based on the study site, the prevalence of Diarrheagenic E. coli and Nontyphoidal Salmonella was higher in children from urban than those from rural. However, the occurrence of each pathogen had no significant differences (P > .05) between settings. The high pathogens occurrence rate in the current study indicates the need for strong control strategies and better child carrying and treatment of diarrheal diseases at both urban and rural settings. Further studies on possible sources and factors attributing to the occurrence of enteric pathogens in children are also recommended.
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Affiliation(s)
- Dinaol Belina
- College of Veterinary Medicine, Haramaya University, Dire Dawa, Ethiopia
- School of Biological Sciences and Biotechnology, Haramaya University, Dire Dawa, Ethiopia
| | - Tesfaye Gobena
- College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Ameha Kebede
- School of Biological Sciences and Biotechnology, Haramaya University, Dire Dawa, Ethiopia
| | - Meseret Chimdessa
- School of Biological Sciences and Biotechnology, Haramaya University, Dire Dawa, Ethiopia
| | - Yonas Hailu
- Teagasc Food Research Centre, Moorepark, Fermoy, County Cork, Ireland
| | - Tine Hald
- National Food Institute, Technical University of Denmark, Lyngby, Denmark
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Ngalo N, Thondhlana G. Illegal Solid-Waste Dumping in a Low-Income Neighbourhood in South Africa: Prevalence and Perceptions. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6750. [PMID: 37754610 PMCID: PMC10530688 DOI: 10.3390/ijerph20186750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/01/2023] [Accepted: 08/10/2023] [Indexed: 09/28/2023]
Abstract
Illegal solid-waste dumping (ISWD) is prevalent globally with adverse social and environmental impacts, particularly in poor communities. Understanding the extent, practices and perceptions of ISWD is needed to inform interventions. Using GIS techniques and household surveys, this study examined the prevalence of dumpsites, and perceptions of ISWD in a low-income neighbourhood of Komani, South Africa. A total of 120 dumpsites were encountered in green spaces, empty residential plots and street edges, suggesting illegal dumping of solid waste is widespread. More than half of the respondents (58%) disposed of household waste in undesignated sites or burnt it, attributing this to the non-collection of waste. Potential interventions suggested were largely technical, including regular collection of waste, and the provision of bins and plastic bags. The paper suggests approaches to addressing sustainable solid-waste management should consider the views of local communities, who are principal stakeholders in the solid-waste production and management mix.
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Affiliation(s)
| | - Gladman Thondhlana
- Department of Environmental Science, Rhodes University, P.O. Box 94, Makhanda 6140, South Africa
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Ballard AM, Laramee N, Haardörfer R, Freeman MC, Levy K, Caruso BA. Measurement in the study of human exposure to animal feces: A systematic review and audit. Int J Hyg Environ Health 2023; 249:114146. [PMID: 36868140 PMCID: PMC10044406 DOI: 10.1016/j.ijheh.2023.114146] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/31/2023] [Accepted: 02/23/2023] [Indexed: 03/05/2023]
Abstract
BACKGROUND Human exposure to animal feces is increasingly recognized as an important transmission route of enteric pathogens. Yet, there are no consistent or standardized approaches to measurement of this exposure, limiting assessment of the human health effects and scope of the issue. OBJECTIVE To inform and improve approaches to the measurement of human exposure to animal feces, we audited existing measurement in low- and middle-income countries. METHODS We systematically searched peer-reviewed and gray literature databases for studies with quantitative measures of human exposure to animal feces and we classified measures in two ways. First, using a novel conceptual model, we categorized measures into three 'Exposure Components' identified a priori (i.e., Animal, Environmental, Human Behavioral); one additional Component (Evidence of Exposure) inductively emerged. Second, using the exposure science conceptual framework, we determined where measures fell along the source-to-outcome continuum. RESULTS We identified 1,428 measures across 184 included studies. Although studies overwhelmingly included more than one single-item measure, the majority only captured one Exposure Component. For example, many studies used several single-item measures to capture the same attribute for different animals, all of which were classified as the same Component. Most measures captured information about the source (e.g. animal presence) and contaminant (e.g. animal-sourced pathogens), which are most distal from exposure on the source-to-outcome continuum. DISCUSSION We found that measurement of human exposure to animal feces is diverse and largely distal from exposure. To facilitate better assessment of the human health effects of exposure and scope of the issue, rigorous and consistent measures are needed. We recommend a list of key factors from the Animal, Environmental, and Human Behavioral Exposure Components to measure. We also propose using the exposure science conceptual framework to identify proximal measurement approaches.
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Affiliation(s)
- April M Ballard
- Gangarosa Department of Environmental Health, Emory University Rollins School of Public Health, Atlanta, GA, USA.
| | - Nicholas Laramee
- Hubert Department of Global Health, Emory University Rollins School of Public Health, Atlanta, GA, USA
| | - Regine Haardörfer
- Department of Behavioral, Social and Health Education Sciences, Emory University Rollins School of Public Health, Atlanta, GA, USA
| | - Matthew C Freeman
- Gangarosa Department of Environmental Health, Emory University Rollins School of Public Health, Atlanta, GA, USA
| | - Karen Levy
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, WA, USA
| | - Bethany A Caruso
- Gangarosa Department of Environmental Health, Emory University Rollins School of Public Health, Atlanta, GA, USA; Hubert Department of Global Health, Emory University Rollins School of Public Health, Atlanta, GA, USA
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High Burden of Co-Infection with Multiple Enteric Pathogens in Children Suffering with Diarrhoea from Rural and Peri-Urban Communities in South Africa. Pathogens 2023; 12:pathogens12020315. [PMID: 36839587 PMCID: PMC9959912 DOI: 10.3390/pathogens12020315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/22/2023] [Accepted: 01/30/2023] [Indexed: 02/17/2023] Open
Abstract
Infectious diarrhoea contributes to high morbidity and mortality in young children from sub-Saharan Africa. The aim of this study was to assess the prevalence of single and multiple diarrhoeal-causing pathogen combinations in children suffering from diarrhoea from rural and peri-urban communities in South Africa. A total of 275 diarrhoea stool specimens were collected between 2014 and 2016 from Hospitals and Primary Health Care clinics. The BioFire® FilmArray® Gastrointestinal panel was used to simultaneously detect 22 diarrhoea pathogens (viruses, bacteria, parasites) known to cause diarrhoea. A total of 82% (226/275) enteric pathogens were detected in the stool specimens. The two most detected bacterial, viral and parasitic pathogens each included: EAEC (42%), EPEC (32%), Adenovirus F40/41 (19%), Norovirus (15%), Giardia (8%) and Cryptosporidium (6%), respectively. Single enteric pathogen infections were recorded in 24% (65/275) specimens with EAEC, and Norovirus was found in 26% (17/65) and 14% (9/65) of the specimens, respectively. Multiple enteric pathogen combinations were recorded in 59% (161/275) of the stool specimens with 53% (85/161) containing two pathogens, 22% (35/161) containing three pathogens and 25% (41/161) containing four or more pathogens. The results from this study demonstrated the complex nature of pathogen co-infections in diarrhoeal episodes which could have an impact on treatment effectiveness.
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11
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Baker KK, Mumma JAO, Simiyu S, Sewell D, Tsai K, Anderson JD, MacDougall A, Dreibelbis R, Cumming O. Environmental and behavioural exposure pathways associated with diarrhoea and enteric pathogen detection in 5-month-old, periurban Kenyan infants: a cross-sectional study. BMJ Open 2022; 12:e059878. [PMID: 36316067 PMCID: PMC9628658 DOI: 10.1136/bmjopen-2021-059878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVES The aim of this study was to test whether household environmental hygiene and behavioural conditions moderated associations between diarrhoea and enteric pathogen detection in infants 5 months of age in Kenya and pathogen sources, including latrine access, domestic animal co-habitation and public food sources. DESIGN Cross-sectional study utilising enrolment survey data of households participating in the Safe Start cluster-randomised controlled trial . SETTING Kisumu, Kenya. PARTICIPANTS A total of 898 caregivers with 5-month (22 week ± 1 week) aged infants were enrolled in the study and completed the enrolment survey. PRIMARY AND SECONDARY OUTCOME MEASURES Outcomes were (1) caregiver-reported 7-day diarrhoea prevalence and (2) count of types of enteric viruses, bacteria and parasites in infant stool. Exposures and effect modifiers included water access and treatment, cohabitation with domestic animals, sanitation access, handwashing practices, supplemental feeding, access to refrigeration and flooring. RESULTS Reported handwashing after handling animals (adjusted odds ratio (aOR)=0.20; 95% CI=0.06 to 0.50) and before eating (aOR=0.44; 95% CI=0.26 to 0.73) were strongly associated with lower risk of caregiver-reported diarrhoea, while cohabitation with animals (aOR=1.54; 95% CI=1.01 to 2.34) living in a household with vinyl-covered dirt floors (aOR=0.60; 95% CI=0.45 to 0.87) were strongly associated with pathogen codetection in infants. Caregiver handwashing after child (p=0.02) or self-defecation (p=0.03) moderated the relationship between shared sanitation access and infant exposure to pathogens, specifically private latrine access was protective against pathogen exposure of infants in households, where caregivers washed hands after defecation. In the absence of handwashing, access to private sanitation posed no benefits over shared latrines for protecting infants from exposure. CONCLUSION Our evidence highlights eliminating animal cohabitation and improving flooring, postdefecation and food-related handwashing, and safety and use of cow milk sources as interventions to prevent enteric pathogen exposure of young infants in Kenya. TRIAL REGISTRATION NUMBER NCT03468114.
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Affiliation(s)
- Kelly K Baker
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa, USA
| | | | - Sheillah Simiyu
- African Population and Health Research Center, Nairobi, Kenya
| | - Daniel Sewell
- Department of Biostatistics, The University of Iowa, Iowa City, Iowa, USA
| | - Kevin Tsai
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa, USA
| | | | - Amy MacDougall
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Robert Dreibelbis
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Oliver Cumming
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
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12
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Glatz Brubakk K, Gjengedal ELF, Enger Ø, Sripada K. Ammunition Waste Pollution and Preliminary Assessment of Risks to Child Health from Toxic Metals at the Greek Refugee Camp Mavrovouni. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:10086. [PMID: 36011717 PMCID: PMC9408271 DOI: 10.3390/ijerph191610086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 08/03/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
The Mavrovouni refugee camp near the former Moria camp on the island of Lesvos, Greece, housed approximately 3000 asylum-seekers including children as of October 2021. The camp was built on the site of a military shooting range. This study aimed to characterize the soil contaminants and assess the risk of toxic environmental exposures for children living in Mavrovouni. Methods: Samples of surface soil (0−2 cm depth; particle size < 2 mm) from eight locations inside the camp were compared with two reference samples. Soil samples were microwave digested using a mixture of nitric and hydrofluoric acids and analyzed for lead (Pb), antimony (Sb), bismuth (Bi), and other metals using inductively coupled plasma mass spectrometry. These values were compared with action limits established by the Norwegian Environment Agency for kindergartens, playgrounds, and schools. Findings: Five of eight soil samples from inside the camp exceeded Pb levels of 100 mg/kg, which is currently the maximum acceptable value of Pb in soil for playgrounds in Norway. Two sites had extreme soil Pb levels of approximately 8000 mg/kg and 6000 mg/kg. The concen-tration of Sb and Bi in the surface soil of the firing range area strongly indicated environmental contamination, most likely from previous military activity and ammunition residue that has re-mained on the surface soil. Concentrations of arsenic (As), cadmium (Cd), copper (Cu), and zinc (Zn) in surface soil were lower than action limits. Discussion: Extremely high levels of Pb, together with high levels of Sb and Bi, were identified in soil where children live and play in the Mavrovouni refugee camp. This is the first independent study of environmental contamination at this camp and adds to the limited evidence base documenting Pb exposures prior to migrant and refugee reset-tlement. On top of the multiple existing public health crises and traumas that these asylum-seeking families face, exposure to toxic ammunition residues may have profound impacts on children’s development and health for years to come.
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Affiliation(s)
- Katrin Glatz Brubakk
- Department of Psychology, Out-Patient Clinic for Children and Adolescents, Norwegian University of Science and Technology (NTNU), NO-7034 Trondheim, Norway
| | - Elin Lovise Folven Gjengedal
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences (NMBU), NO-1432 Aas, Norway
| | - Øyvind Enger
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences (NMBU), NO-1432 Aas, Norway
| | - Kam Sripada
- Centre for Global Health Inequalities Research (CHAIN), Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
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13
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Delva S, Marseille B, Foronda CL, Solomon AY, Pfaff T, Baptiste DL. Hand hygiene practices in Caribbean and Latin American countries: An integrative review. J Clin Nurs 2022; 32:2140-2154. [PMID: 35773957 DOI: 10.1111/jocn.16415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 03/01/2022] [Accepted: 05/16/2022] [Indexed: 11/27/2022]
Abstract
AIM AND OBJECTIVE To explore what is known about knowledge, attitudes and beliefs that influence hand hygiene practices in in low- and middle-income Caribbean and Latin American countries. BACKGROUND With the emergence of infectious diseases such as the recent COVID-19 pandemic, handwashing is key to preventing communicable diseases as they disproportionately affect populations in low-income countries. While hand hygiene is known to be the single most effective method for avoiding the transmission of infection, little is known about the beliefs and practices of individuals in these regions. METHODS Following PRISMA 2020 Checklist, an integrative review of studies published from 2008-2020 was conducted (Preferred Reporting Items for Systematic Reviews and Meta-analyses). Whittemore and Knafl's method was used to review the literature. Six databases were searched, and the Johns Hopkins Evidence Based Rating Scale was used for study appraisal. RESULTS The review yielded 18 studies conducted across Latin America. Poor handwashing practices are influenced by various factors including inadequate education and training, cultural beliefs, lack of resources and substandard government regulations. Communicable diseases and other diarrheal illnesses were highly prevalent, especially after a major disease outbreak. CONCLUSION Future post-disaster campaigns aimed at improving hand hygiene and handwashing practices should focus on beliefs and attitudes to affect behaviour change since there was a higher disease susceptibility during those times. Barriers to proper hand hygiene include false attitudes such as, washing hands only after touching bodily fluids/patient contact or not washing hands at all after open defecation. RELEVANCE TO CLINICAL PRACTICE Researchers working with populations in Latin America and the Caribbean should partner with local community health workers to improve compliance to recommended hand hygiene practices.
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Affiliation(s)
- Sabianca Delva
- Boston College Connell School of Nursing, Chestnut Hill, Massachusetts, USA
| | | | - Cynthia L Foronda
- School of Nursing and Health Studies, University of Miami, Coral Gables, Florida, USA
| | | | - Teresa Pfaff
- Center for Global Initiatives, Department of Community-Public Health, Johns Hopkins University School of Nursing, Baltimore, Maryland, USA
| | - Diana-Lyn Baptiste
- Department of Nursing, Johns Hopkins School of Nursing, Baltimore, Maryland, USA
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14
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Sosa-Moreno A, Lee GO, Van Engen A, Sun K, Uruchima J, Kwong LH, Ludwig-Borycz E, Caruso BA, Cevallos W, Levy K, Eisenberg JNS. Characterizing Behaviors Associated with Enteric Pathogen Exposure among Infants in Rural Ecuador through Structured Observations. Am J Trop Med Hyg 2022; 106:tpmd211099. [PMID: 35405653 PMCID: PMC9209906 DOI: 10.4269/ajtmh.21-1099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 01/31/2022] [Indexed: 11/07/2022] Open
Abstract
The relative importance of environmental pathways that results in enteropathogen transmission may vary by context. However, measurement of contact events between individuals and the environment remains a challenge, especially for infants and young children who may use their mouth and hands to explore their environment. Using a mixed-method approach, we combined 1) semistructured observations to characterize key behaviors associated with enteric pathogen exposure and 2) structured observations using Livetrak, a customized software application, to quantify the frequency and duration of contacts events among infants in rural Ecuador. After developing and iteratively piloting the structured observation instrument, we loaded the final list of prompts onto a LiveTrak pallet to assess environmental exposures of 6-month infants (N = 19) enrolled in a prospective cohort study of diarrheal disease. Here we provide a detailed account of the lessons learned. For example, in our field site, 1) most mothers reported washing their hands after diaper changes (14/18, 77.8%); however only a third (4/11, 36.4%) were observed washing their hands; 2) the observers noted that animal ownership differed from observed animal exposure because animals owned by neighboring households were reported during the observation; and 3) using Livetrak, we found that infants frequently mouthed their hands (median = 1.9 episodes/hour, median duration: 1.6 min) and mouthed surroundings objects (1.8 episodes/hour, 1.9 min). Structured observations that track events in real time, can complement environmental sampling, quantitative survey data and qualitative interviews. Customizing these observations enabled us to quantify enteric exposures most relevant to our rural Ecuadorian context.
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Affiliation(s)
| | - Gwenyth O. Lee
- School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Amanda Van Engen
- School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Kelly Sun
- School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Jessica Uruchima
- School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Laura H. Kwong
- School of Public Health, University of California Berkeley, Berkeley, California
| | | | - Bethany A. Caruso
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | | | - Karen Levy
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington
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15
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Mwapasa T, Chidziwisano K, Lally D, Morse T. Hygiene in early childhood development centres in low-income areas of Blantyre, Malawi. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2022:1-17. [PMID: 35272551 DOI: 10.1080/09603123.2022.2048802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 02/26/2022] [Indexed: 06/14/2023]
Abstract
Diarrhoeal disease remains a leading cause of death in children in sub-Saharan Africa, attributed to environmental health factors such as inadequate water, sanitation and hygiene (WASH) and food hygiene. This formative study in low-income areas of Blantyre focussed on the practices in Early Childhood Development Centre (ECDCs) environments where children spend a significant amount of time. A mixed-methods approach was applied to identify key hygiene behaviours in ECDCs through; checklist and structured observations (n = 849 children; n = 33 caregivers), focus group discussions (n = 25) and microbiological sampling (n = 261) of drinking water, food handler's hands, and eating utensils. ECDCs had inadequate WASH infrastructure; coupled with poor hygiene practices and unhygienic environments increased the risk of faecal-oral disease transmission. Presence of E. coli in drinking water confirmed observed poor water handling habits by staff and children. Addressing undesired hygiene practices in ECDCs has the potential to improve the health outcomes of children in low-income settings.
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Affiliation(s)
- Taonga Mwapasa
- Centre for Water, Sanitation, Health and Appropriate Technology Development (WASHTED), University of Malawi - The Polytechnic, Blantyre, Malawi
| | - Kondwani Chidziwisano
- Centre for Water, Sanitation, Health and Appropriate Technology Development (WASHTED), University of Malawi - The Polytechnic, Blantyre, Malawi
- Department of Environmental Health, University of Malawi - The Polytechnic, Blantyre, Malawi
| | - David Lally
- Centre for Water, Sanitation, Health and Appropriate Technology Development (WASHTED), University of Malawi - The Polytechnic, Blantyre, Malawi
| | - Tracy Morse
- Centre for Water, Sanitation, Health and Appropriate Technology Development (WASHTED), University of Malawi - The Polytechnic, Blantyre, Malawi
- Department of Civil and Environmental Engineering, University of Strathclyde, Glasgow, UK
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16
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Haywood LK, Kapwata T, Oelofse S, Breetzke G, Wright CY. Waste Disposal Practices in Low-Income Settlements of South Africa. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18158176. [PMID: 34360468 PMCID: PMC8346154 DOI: 10.3390/ijerph18158176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/22/2021] [Accepted: 07/27/2021] [Indexed: 11/16/2022]
Abstract
Domestic solid waste is rapidly increasing due to accelerated population growth and urbanization. Improper waste disposal poses potential health risks and environmental concerns. Here, we investigated waste disposal practices in relation to household/dwelling characteristics in South African low-income communities. Data for 2014 to 2019 from a community-orientated primary care program were analyzed using logistic regression. Families who reported living in a shack were more likely to dump waste in the street. Households who reported using non-electric sources of fuel for heating/cooking, those who lacked proper sanitation, and those who did not have access to piped water inside the dwelling were more likely to dispose of waste by dumping it in the street/in the yard or burying it. Families living in low-income settlements are at risk of solid waste exposure and this situation is exacerbated by poor access to piped water, proper sanitation, and electricity.
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Affiliation(s)
- Lorren Kirsty Haywood
- Smart Places, Council of Scientific and Industrial Research (CSIR), Pretoria 0001, South Africa;
- Correspondence:
| | - Thandi Kapwata
- Environment and Health Research Unit, South African Medical Research Council, Johannesburg 2094, South Africa;
- Department of Environmental Health, Faculty of Health Sciences, University of Johannesburg, P.O. Box 524, Auckland Park 2006, South Africa
| | - Suzan Oelofse
- Smart Places, Council of Scientific and Industrial Research (CSIR), Pretoria 0001, South Africa;
- Unit for Environmental Science and Management, North West University, Pothchefstroom 2502, South Africa
| | - Gregory Breetzke
- Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria 0002, South Africa; (G.B.); (C.Y.W.)
| | - Caradee Yael Wright
- Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria 0002, South Africa; (G.B.); (C.Y.W.)
- Environment and Health Research Unit, South African Medical Research Council, Pretoria 0001, South Africa
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17
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Overgaard HJ, Dada N, Lenhart A, Stenström TAB, Alexander N. Integrated disease management: arboviral infections and waterborne diarrhoea. Bull World Health Organ 2021; 99:583-592. [PMID: 34354313 PMCID: PMC8319858 DOI: 10.2471/blt.20.269985] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 02/15/2021] [Accepted: 03/08/2021] [Indexed: 11/27/2022] Open
Abstract
Water-related diseases such as diarrhoeal diseases from viral, bacterial and parasitic organisms and Aedes-borne arboviral diseases are major global health problems. We believe that these two disease groups share common risk factors, namely inadequate household water management, poor sanitation and solid waste management. Where water provision is inadequate, water storage is essential. Aedes mosquitoes commonly breed in household water storage containers, which can hold water contaminated with enteric disease-causing organisms. Microbiological contamination of water between source and point-of-use is a major cause of reduced drinking-water quality. Inadequate sanitation and solid waste management increase not only risk of water contamination, but also the availability of mosquito larval habitats. In this article we discuss integrated interventions that interrupt mosquito breeding while also providing sanitary environments and clean water. Specific interventions include improving storage container design, placement and maintenance and scaling up access to piped water. Vector control can be integrated into sanitation projects that target sewers and drains to avoid accumulation of stagnant water. Better management of garbage and solid waste can reduce the availability of mosquito habitats while improving human living conditions. Our proposed integration of disease interventions is consistent with strategies promoted in several global health frameworks, such as the sustainable development goals, the global vector control response, behavioural change, and water, sanitation and hygiene initiatives. Future research should address how interventions targeting water, sanitation, hygiene and community waste disposal also benefit Aedes-borne disease control. The projected effects of climate change mean that integrated management and control strategies will become increasingly important.
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Affiliation(s)
- Hans J Overgaard
- Faculty of Science and Technology, Drøbakveien 31, Norwegian University of Life Sciences, NO - 1432 Ås, Norway
| | - Nsa Dada
- Faculty of Science and Technology, Drøbakveien 31, Norwegian University of Life Sciences, NO - 1432 Ås, Norway
| | - Audrey Lenhart
- Center for Global Health, United States Centers for Disease Control and Prevention, Atlanta, United States of America
| | - Thor Axel B Stenström
- Institute for Water and Wastewater Technology, Durban University of Technology, Durban, South Africa
| | - Neal Alexander
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, England
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18
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Kraay ANM, Man O, Levy MC, Levy K, Ionides E, Eisenberg JNS. Understanding the Impact of Rainfall on Diarrhea: Testing the Concentration-Dilution Hypothesis Using a Systematic Review and Meta-Analysis. ENVIRONMENTAL HEALTH PERSPECTIVES 2020; 128:126001. [PMID: 33284047 PMCID: PMC7720804 DOI: 10.1289/ehp6181] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/26/2020] [Accepted: 11/09/2020] [Indexed: 05/07/2023]
Abstract
BACKGROUND Projected increases in extreme weather may change relationships between rain-related climate exposures and diarrheal disease. Whether rainfall increases or decreases diarrhea rates is unclear based on prior literature. The concentration-dilution hypothesis suggests that these conflicting results are explained by the background level of rain: Rainfall following dry periods can flush pathogens into surface water, increasing diarrhea incidence, whereas rainfall following wet periods can dilute pathogen concentrations in surface water, thereby decreasing diarrhea incidence. OBJECTIVES In this analysis, we explored the extent to which the concentration-dilution hypothesis is supported by published literature. METHODS To this end, we conducted a systematic search for articles assessing the relationship between rain, extreme rain, flood, drought, and season (rainy vs. dry) and diarrheal illness. RESULTS A total of 111 articles met our inclusion criteria. Overall, the literature largely supports the concentration-dilution hypothesis. In particular, extreme rain was associated with increased diarrhea when it followed a dry period [incidence rate ratio ( IRR ) = 1.26 ; 95% confidence interval (CI): 1.05, 1.51], with a tendency toward an inverse association for extreme rain following wet periods, albeit nonsignificant, with one of four relevant studies showing a significant inverse association (IRR = 0.911 ; 95% CI: 0.771, 1.08). Incidences of bacterial and parasitic diarrhea were more common during rainy seasons, providing pathogen-specific support for a concentration mechanism, but rotavirus diarrhea showed the opposite association. Information on timing of cases within the rainy season (e.g., early vs. late) was lacking, limiting further analysis. We did not find a linear association between nonextreme rain exposures and diarrheal disease, but several studies found a nonlinear association with low and high rain both being associated with diarrhea. DISCUSSION Our meta-analysis suggests that the effect of rainfall depends on the antecedent conditions. Future studies should use standard, clearly defined exposure variables to strengthen understanding of the relationship between rainfall and diarrheal illness. https://doi.org/10.1289/EHP6181.
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Affiliation(s)
- Alicia N. M. Kraay
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Olivia Man
- Department of Epidemiology, University of Michigan–Ann Arbor, Ann Arbor, Michigan, USA
| | - Morgan C. Levy
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
- School of Global Policy and Strategy, University of California San Diego, La Jolla, California, USA
| | - Karen Levy
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington, USA
| | - Edward Ionides
- Department of Epidemiology, University of Michigan–Ann Arbor, Ann Arbor, Michigan, USA
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19
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Fuhrmeister E, Ercumen A, Pickering AJ, Jeanis KM, Crider Y, Ahmed M, Brown S, Alam M, Sen D, Islam S, Kabir MH, Islam M, Rahman M, Kwong LH, Arnold BF, Luby SP, Colford JM, Nelson KL. Effect of Sanitation Improvements on Pathogens and Microbial Source Tracking Markers in the Rural Bangladeshi Household Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:4316-4326. [PMID: 32167305 PMCID: PMC7144219 DOI: 10.1021/acs.est.9b04835] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 05/19/2023]
Abstract
Diarrheal illnesses from enteric pathogens are a leading cause of death in children under five in low- and middle-income countries (LMICs). Sanitation is one way to reduce the spread of enteric pathogens in the environment; however, few studies have investigated the effectiveness of sanitation in rural LMICs in reducing pathogens in the environment. In this study, we measured the impact of a sanitation intervention (dual-pit latrines, sani-scoops, child potties delivered as part of a randomized control trial, WASH Benefits) in rural Bangladeshi household compounds by assessing prevalence ratios, differences, and changes in the concentration of pathogen genes and host-specific fecal markers. We found no difference in the prevalence of pathogenic Escherichia coli, norovirus, or Giardia genes in the domestic environment in the sanitation and control arms. The prevalence of the human fecal marker was lower on child hands and the concentration of animal fecal marker was lower on mother hands in the sanitation arm in adjusted models, but these associations were not significant after correcting for multiple comparisons. In the subset of households with ≥10 individuals per compound, the prevalence of enterotoxigenic E. coli genes on child hands was lower in the sanitation arm. Incomplete removal of child and animal feces or the compound (versus community-wide) scale of intervention could explain the limited impacts of improved sanitation.
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Affiliation(s)
- Erica
R. Fuhrmeister
- Department
of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Ayse Ercumen
- School
of Public Health, University of California, Berkeley, California 94720, United States
- Department
of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Amy J. Pickering
- Civil
and Environmental Engineering, Tufts University, Medford, Massachusetts 02153, United States
| | - Kaitlyn M. Jeanis
- Department
of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Yoshika Crider
- Energy
and Resources Group, University of California, Berkeley, California 94720, United States
| | - Mahaa Ahmed
- Department
of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Sara Brown
- Department
of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Mahfuja Alam
- Infectious
Disease Division, International Centre for
Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Debashis Sen
- Infectious
Disease Division, International Centre for
Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Sharmin Islam
- Infectious
Disease Division, International Centre for
Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Mir Himayet Kabir
- Infectious
Disease Division, International Centre for
Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Mahfuza Islam
- Infectious
Disease Division, International Centre for
Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Mahbubur Rahman
- Infectious
Disease Division, International Centre for
Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Laura H. Kwong
- Department
of Civil and Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Benjamin F. Arnold
- School
of Public Health, University of California, Berkeley, California 94720, United States
| | - Stephen P. Luby
- Woods
Institute for the Environment, Stanford
University, Stanford, California 94305, United States
| | - John M. Colford
- School
of Public Health, University of California, Berkeley, California 94720, United States
| | - Kara L. Nelson
- Department
of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
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20
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Chard AN, Levy K, Baker KK, Tsai K, Chang HH, Thongpaseuth V, Sistrunk JR, Freeman MC. Environmental and spatial determinants of enteric pathogen infection in rural Lao People's Democratic Republic: A cross-sectional study. PLoS Negl Trop Dis 2020; 14:e0008180. [PMID: 32267881 PMCID: PMC7170279 DOI: 10.1371/journal.pntd.0008180] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 04/20/2020] [Accepted: 02/28/2020] [Indexed: 01/10/2023] Open
Abstract
TRIAL REGISTRATION clinicaltrials.gov (NCT02342860).
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Affiliation(s)
- Anna N. Chard
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Karen Levy
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Kelly K. Baker
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa, United States of America
| | - Kevin Tsai
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa, United States of America
| | - Howard H. Chang
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Vonethalom Thongpaseuth
- Laboratory and Treatment Unit, Center for Malariology, Parasitology, and Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Jeticia R. Sistrunk
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Matthew C. Freeman
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
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Gough EK, Moulton LH, Mutasa K, Ntozini R, Stoltzfus RJ, Majo FD, Smith LE, Panic G, Giallourou N, Jamell M, Kosek P, Swann JR, Humphrey JH, Prendergast AJ. Effects of improved water, sanitation, and hygiene and improved complementary feeding on environmental enteric dysfunction in children in rural Zimbabwe: A cluster-randomized controlled trial. PLoS Negl Trop Dis 2020; 14:e0007963. [PMID: 32059011 PMCID: PMC7046282 DOI: 10.1371/journal.pntd.0007963] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/27/2020] [Accepted: 11/27/2019] [Indexed: 12/21/2022] Open
Abstract
Background Environmental enteric dysfunction (EED) may be an important modifiable cause of child stunting. We described the evolution of EED biomarkers from birth to 18 months in rural Zimbabwe and tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF), on EED. Methodology and findings The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial was a 2x2 factorial cluster-randomised trial of improved IYCF and improved WASH on child stunting and anaemia at 18 months of age. 1169 infants born to HIV-negative mothers provided plasma and faecal specimens at 1, 3, 6, 12, and 18 months of age. We measured EED biomarkers that reflect all domains of the hypothesized pathological pathway. Markers of intestinal permeability and intestinal inflammation declined over time, while markers of microbial translocation and systemic inflammation increased between 1–18 months. Markers of intestinal damage (I-FABP) and repair (REG-1β) mirrored each other, and citrulline (a marker of intestinal epithelial mass) increased from 6 months of age, suggesting dynamic epithelial turnover and regeneration in response to enteric insults. We observed few effects of IYCF and WASH on EED after adjustment for multiple comparisons. The WASH intervention decreased plasma IGF-1 at 3 months (β:0.89, 95%CI:0.81,0.98) and plasma kynurenine at 12 months (β: 0.92, 95%CI:0.87,0.97), and increased plasma IGF-1 at 18 months (β:1.15, 95%CI:1.05,1.25), but these small WASH effects did not translate into improved growth. Conclusions Overall, we observed dynamic trends in EED but few effects of IYCF or WASH on biomarkers during the first 18 months after birth, suggesting that these interventions did not impact EED. Transformative WASH interventions are required to prevent or ameliorate EED in low-income settings. Child stunting remains a global health challenge rooted in an intergenerational cycle of poor health, reduced neurodevelopment and poverty. Environmental enteric dysfunction (EED) is an acquired condition of the small intestine likely resulting from frequent faecal-oral microbial exposure, which is hypothesized to underlie stunting. We found dynamic changes in EED biomarkers between 1 and 18 months of age in a cohort of rural Zimbabwean infants, suggesting a complex developmental period of intestinal maturation, adaptation and response to environmental insults. Randomized improved infant and young child feeding, and improved water, sanitation and hygiene (WASH) interventions had no meaningful impact on EED. Greater investment in transformative WASH is needed to prevent EED in low-income countries.
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Affiliation(s)
- Ethan K. Gough
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- * E-mail:
| | - Lawrence H. Moulton
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | - Kuda Mutasa
- Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
| | - Robert Ntozini
- Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
| | - Rebecca J. Stoltzfus
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, United States of America
| | - Florence D. Majo
- Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
| | - Laura E. Smith
- Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo, Buffalo, NY, United States of America
| | - Gordana Panic
- Department of Metabolism, Digestion and Reproduction, Division of Digestive Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Natasa Giallourou
- Department of Metabolism, Digestion and Reproduction, Division of Digestive Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Mark Jamell
- Pain Care Specialists of Oregon, Eugene, OR, United States of America
| | - Peter Kosek
- Pain Care Specialists of Oregon, Eugene, OR, United States of America
| | - Jonathan R. Swann
- Department of Metabolism, Digestion and Reproduction, Division of Digestive Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
- Department of Neuroscience, Karolinska Institute, Solna, Sweden
| | - Jean H. Humphrey
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
| | - Andrew J. Prendergast
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
- Blizard Institute, Queen Mary University of London, London, United Kingdom
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Brown J, Hayashi MAL, Eisenberg JNS. The Critical Role of Compliance in Delivering Health Gains from Environmental Health Interventions. Am J Trop Med Hyg 2020; 100:777-779. [PMID: 30675842 DOI: 10.4269/ajtmh.18-0624] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Gains in reducing childhood disease burden rely heavily on effective means of preventing environmental exposures. For many environmental health interventions, such as point-of-use water treatment, sanitation, or cookstoves, exposures are strongly influenced by user behaviors and the degree to which participants adhere to the prescribed preventive measures. In this commentary, we articulate the need for increased attention on user behaviors-critically, the careful measurement and inclusion of compliance-to strengthen exposure assessment and health impact trials in environmental health intervention research. We focus here on water, sanitation, and hygiene interventions to illustrate the problem with the understanding that this issue extends to other environmental health interventions.
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Affiliation(s)
- Joe Brown
- Georgia Institute of Technology, Atlanta, Georgia
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The landscape of enteric pathogen exposure of young children in public domains of low-income, urban Kenya: The influence of exposure pathway and spatial range of play on multi-pathogen exposure risks. PLoS Negl Trop Dis 2019; 13:e0007292. [PMID: 30917117 PMCID: PMC6453472 DOI: 10.1371/journal.pntd.0007292] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 04/08/2019] [Accepted: 03/12/2019] [Indexed: 11/19/2022] Open
Abstract
Young children are infected by a diverse variety of enteric pathogens in low-income, high-burden countries. Little is known about which conditions pose the greatest risk for enteric pathogen exposure and infection. Young children frequently play in residential public areas around their household, including areas contaminated by human and animal feces, suggesting these exposures are particularly hazardous. The objective of this study was to examine how the dose of six types of common enteric pathogens, and the probability of exposure to one or multiple enteric pathogens for young children playing at public play areas in Kisumu, Kenya is influenced by the type and frequency of child play behaviors that result in ingestion of soil or surface water. Additionally, we examine how pathogen doses and multi-pathogen exposure are modified by spatial variability in the number of public areas children are exposed to in their neighborhood. A Bayesian framework was employed to obtain the posterior distribution of pathogen doses for a certain number of contacts. First, a multivariate mixed effects tobit model was used to obtain the posterior distribution of pathogen concentrations, and their interdependencies, in soil and surface water, based upon empirical data of enteric pathogen contamination in three neighborhoods of Kisumu. Then, exposure doses were estimated using behavioral contact parameters from previous studies and contrasted under different exposure conditions. Pathogen presence and concentration in soil varied widely across local (< 25 meter radius area) and neighborhood-level scales, but pathogens were correlated among distinct surface water samples collected near to each other. Multi-pathogen exposure of children at public play areas was common. Pathogen doses and the probability of multi-pathogen ingestion increased with: higher frequency of environmental contact, especially for surface water; larger volume of soil or water ingested; and with play at multiple sites in the neighborhood versus single site play. Child contact with surface water and soil at public play areas in their neighborhood is an important cause of exposure to enteric pathogens in Kisumu, and behavioral, environmental, and spatial conditions are determinants of exposure.
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Baker KK, Senesac R, Sewell D, Gupta AS, Cumming O, Mumma J. Fecal Fingerprints of Enteric Pathogen Contamination in Public Environments of Kisumu, Kenya, Associated with Human Sanitation Conditions and Domestic Animals. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:10263-10274. [PMID: 30106283 PMCID: PMC6557411 DOI: 10.1021/acs.est.8b01528] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Young children are infected by a diverse range of enteric pathogens in high disease burden settings, suggesting pathogen contamination of the environment is equally diverse. This study aimed to characterize across- and within-neighborhood diversity in enteric pathogen contamination of public domains in urban informal settlements of Kisumu, Kenya, and to assess the relationship between pathogen detection patterns and human and domestic animal sanitation conditions. Microbial contamination of soil and surface water from 166 public sites in three Kisumu neighborhoods was measured by enterococcal assays and quantitative reverse transcription polymerase chain reaction (qRT-PCR) for 19 enteric pathogens. Regression was used to assess the association between observed sanitary indicators of contamination with enterococci and pathogen presence and concentration, and pathogen diversity. Seventeen types of pathogens were detected in Kisumu public domains. Enteric pathogens were codetected in 33% of soil and 65% of surface water samples. Greater pathogen diversity was associated with the presence of domestic animal feces but not with human open defecation, deteriorating latrines, flies, or disposal of human feces. Sanitary conditions were not associated with enterococcal bacteria, specific pathogen concentrations, or "any pathogen". Young children played at 40% of observed sites. Managing domestic animal feces may be required to reduce enteric pathogen environmental contamination in high-burden settings.
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Affiliation(s)
- Kelly K. Baker
- Department of Occupational and Environmental Health
- Corresponding Author Phone: (001) 319-384-4008;.
| | - Reid Senesac
- Department of Occupational and Environmental Health
| | | | - Ananya Sen Gupta
- Department of Electrical Engineering, University of Iowa, Iowa City, Iowa 52242, United States
| | - Oliver Cumming
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom
| | - Jane Mumma
- Department of Community Nutrition, Great Lakes University of Kisumu, 40100 Kisumu, Kenya
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