96 research outputs found

    Human to human transmission of H7N9.

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    Diarrhoeal disease outbreaks associated with sanitation provision failures in refugee camps worldwide: a literature review

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    The objective of this review is to identify sanitation failures that have contributed to the occurrence of diarrhoeal disease outbreaks among displaced populations living in camps. Three electronic databases (Medline, Embase, Global Health) and reference lists were searched for peer-reviewed literature using a systematic approach. Articles published since 1960 describing both diarrhoeal disease outbreaks and sanitation characteristics in camps hosting displaced populations were included. Evidence linking outbreaks to sanitation-related factors was synthesized and critically appraised. The search yielded 608 articles, of which 12 met inclusion criteria. They described cholera and shigellosis outbreaks occurring in 21 different camps between 1974 and 2009. Recurring contributing factors across outbreaks included a sudden population influx, inadequate provision or maintenance of latrines, sudden rains, and insufficient safe water quantities. Most studies were descriptive only or did not consider sanitation-related exposures in risk factor analyses. However, two case-control studies found that cases were significantly more likely than controls to share latrines with several households. Two other case-control studies identified an increased risk of infection from exposure to drinking contaminated river or shallow well water. Evidence from previous outbreak investigations illustrates how sanitation failures, particularly following population influxes, can contribute to the occurrence of diarrhoeal disease outbreaks in refugee camps. Further development and application of sanitation assessment tools and metrics would enable more robust evaluation of risks associated with specific sanitation-related exposures and the effectiveness of interventions. Recent guidelines address the identified risk factors but stakeholders should be aware of the impact of population dynamics

    Distribution of selected healthcare resources for influenza pandemic response in Cambodia.

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    INTRODUCTION: Human influenza infection poses a serious public health threat in Cambodia, a country at risk for the emergence and spread of novel influenza viruses with pandemic potential. Prior pandemics demonstrated the adverse impact of influenza on poor communities in developing countries. Investigation of healthcare resource distribution can inform decisions regarding resource mobilization and investment for pandemic mitigation. METHODS: A health facility survey performed across Cambodia obtained data on availability of healthcare resources important for pandemic influenza response. Focusing on five key resources considered most necessary for treating severe influenza (inpatient beds, doctors, nurses, oseltamivir, and ventilators), resource distributions were analyzed at the Operational District (OD) and Province levels, refining data analysis from earlier studies. Resources were stratified by respondent type (hospital vs. District Health Office [DHO]). A summary index of distribution inequality was calculated using the Gini coefficient. Indices for local spatial autocorrelation were measured at the OD level using geographical information system (GIS) analysis. Finally, a potential link between socioeconomic status and resource distribution was explored by mapping resource densities against poverty rates. RESULTS: Gini coefficient calculation revealed variable inequality in distribution of the five key resources at the Province and OD levels. A greater percentage of the population resides in areas of relative under-supply (28.5%) than over-supply (21.3%). Areas with more resources per capita showed significant clustering in central Cambodia while areas with fewer resources clustered in the northern and western provinces. Hospital-based inpatient beds, doctors, and nurses were most heavily concentrated in areas of the country with the lowest poverty rates; however, beds and nurses in Non-Hospital Medical Facilities (NHMF) showed increasing concentrations at higher levels of poverty. CONCLUSIONS: There is considerable heterogeneity in healthcare resource distribution across Cambodia. Distribution mapping at the local level can inform policy decisions on where to stockpile resources in advance of and for reallocation in the event of a pandemic. These findings will be useful in determining future health resource investment, both for pandemic preparedness and for general health system strengthening, and provide a foundation for future analyses of equity in health services provision for pandemic mitigation planning in Cambodia

    Exploring why animal health practices are (not) adopted among smallholders in low and middle-income countries: a realist framework and scoping review protocol

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    BackgroundImproving livestock health is considered critical to address poverty, malnutrition and food insecurity in low- and middle-income countries (LMICs). Modifications of livestock management practices is also increasingly recognized as an important strategy to mitigate global threats such as climate change and novel disease emergence. Smallholders are, however, under various constraints which prohibit them from altering health practices for livestock and little is known about how the adoption of these practices may be promoted. The proposed scoping review aims to systematically map evidence around “what practices are (not) adopted by smallholders under what circumstances, how and why?.”Method and analysisWe conducted initial scoping searches to broadly define types of animal health practices relevant for smallholders in LMICs and formulated search terms. A scoping review protocol was designed and registered. A systematic literature search will be conducted using electronic databases including CAB Abstract, Scopus, MEDLINE, EMBASE, and Web of Science Core Collection. Gray literature will be searched from AGRIS and Standards for Supporting Agricultural Livelihoods in Emergencies. Articles in English, pertaining to the animal health practices considered highly relevant will be considered eligible for inclusion. Articles will be screened at two stages by two independent reviewers; screening of titles, abstracts, and keywords, followed by full-article screening. The first reviewer will review 100% of the articles at both stages. The second reviewer will review a random sample of 20% of the articles at both stages. Any disagreements will be resolved using inputs from the third reviewer. A thematic analysis will be conducted to catalog contexts and mechanisms for adoption and discussed under a realist framework.DiscussionUnderstanding of the mechanisms underlying the adoption of animal health practices by livestock smallholders in LMICs is crucial for successful implementation of interventions including those which are based on a One Health approach. This review will identify the extent of this knowledge across disciplines and inform future research priorities for the design of effective and feasible interventions which can contribute toward Sustainable Development Goal 2.RegistrationThis protocol is registered within the Open Science Framework (https://doi.org/10.17605/OSF.IO/FUQAX)

    Mapping emerging trends and South–South cooperation in regional knowledge networks: A bibliometric analysis of avian influenza research in Southeast Asia

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    This paper maps emerging trends and South-South cooperation in regional knowledge networks through a bibliometric analysis of avian influenza research in Southeast Asia, between 2004 and 2019. The findings indicate that a substantial research output involving researchers and organisations in the region was generated. However, wide disparities between countries existed, both in terms of output and participation in the regional network, which was largely driven by non-regional actors. A more proactive involvement of institutions for regional cooperation such as the Association of Southeast Asian Nations (ASEAN) would increase local ownership, sustainability and redress imbalances in the regional research system

    Characterization of Intrinsic Properties of Promoters.

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    Accurate characterization of promoter behavior is essential for the rational design of functional synthetic transcription networks such as logic gates and oscillators. However, transcription rates observed from promoters can vary significantly depending on the growth rate of host cells and the experimental and genetic contexts of the measurement. Furthermore, in vivo measurement methods must accommodate variation in translation, protein folding, and maturation rates of reporter proteins, as well as metabolic load. The external factors affecting transcription activity may be considered to be extrinsic, and the goal of characterization should be to obtain quantitative measures of the intrinsic characteristics of promoters. We have developed a promoter characterization method that is based on a mathematical model for cell growth and reporter gene expression and exploits multiple in vivo measurements to compensate for variation due to extrinsic factors. First, we used optical density and fluorescent reporter gene measurements to account for the effect of differing cell growth rates. Second, we compared the output of reporter genes to that of a control promoter using concurrent dual-channel fluorescence measurements. This allowed us to derive a quantitative promoter characteristic (ρ) that provides a robust measure of the intrinsic properties of a promoter, relative to the control. We imposed different extrinsic factors on growing cells, altering carbon source and adding bacteriostatic agents, and demonstrated that the use of ρ values reduced the fraction of variance due to extrinsic factors from 78% to less than 4%. This is a simple and reliable method to quantitatively describe promoter properties.TJR was supported by a Microsoft Research studentship and EC FP7 Project No. 612146 (PLASWIRES) awarded to JH, JRB by a Microsoft Research studentship and internship, and FF by CONICYT-PAI/Concurso Nacional de Apoyo al Retorno de Investigadores/as desde el Extranjero Folio 8213002 7, and EPSRC grant EP/H019162/1 awarded to JH. JWA acknowledges the EPSRC and the Wellcome Trust for support.This is the author accepted manuscript. The final version is available from ACS via http://dx.doi.org/10.1021/acssynbio.5b0011

    Simulating contact networks for livestock disease epidemiology: a systematic review

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    Contact structure among livestock populations influences the transmission of infectious agents among them. Models simulating realistic contact networks therefore have important applications for generating insights relevant to livestock diseases. This systematic review identifies and compares such models, their applications, data sources and how their validity was assessed. From 52 publications, 37 models were identified comprising seven model frameworks. These included mathematical models (n = 8; including generalized random graphs, scale-free, Watts-Strogatz and spatial models), agent-based models (n = 8), radiation models (n = 1) (collectively, considered 'mechanistic'), gravity models (n = 4), exponential random graph models (n = 9), other forms of statistical model (n = 6) (statistical) and random forests (n = 1) (machine learning). Overall, nearly half of the models were used as inputs for network-based epidemiological models. In all models, edges represented livestock movements, sometimes alongside other forms of contact. Statistical models were often applied to infer factors associated with network formation (n = 12). Mechanistic models were commonly applied to assess the interaction between network structure and disease dissemination (n = 6). Mechanistic, statistical and machine learning models were all applied to generate networks given limited data (n = 13). There was considerable variation in the approaches used for model validation. Finally, we discuss the relative strengths and weaknesses of model frameworks in different use cases

    Epidemiology and serotype distribution of Streptococcus pneumoniae carriage among influenza-like illness cases in metropolitan Vientiane, Lao PDR: a community-based cohort study

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    BackgroundData on the epidemiology of Streptococcus pneumoniae among influenza-like illness (ILI) cases, particularly in low- and middle-income countries are scarce. This study assessed the prevalence, risk factors and serotype distribution of S. pneumoniae carriage among ILI cases in metropolitan Vientiane, Lao People's Democratic Republic. The 13-valent pneumococcal conjugate vaccine (PCV13) was introduced among infants in October 2013.MethodsActive ILI surveillance was conducted through weekly phone calls in an open community-based cohort study (April 2015–February 2019), involving 5,690 participants from 1,142 randomly selected households. Participants reporting ILI symptoms provided a nasopharyngeal swab and answered a questionnaire. S. pneumoniae and serotype pneumococcal-positive samples were screened by Multiplex PCR assays. Chi-squared tests and generalized linear mixed models were used to test for variables associated with pneumococcal positivity.ResultsAmong 1,621 ILI episodes, 269 (16.6%) tested positive for nasopharyngeal pneumococcal carriage, with the highest prevalence (55.4%) in children under 5 years. Pneumococcal carriage was significantly associated with concurrent detection of Hemophilus influenzae (adjusted odds ratio [aOR]: 6.93; 95% CI: 2.10–22.9) and exposure to household cigarette smoke (aOR: 1.65; 95% CI: 1.07–2.54). PCV13 serotypes accounted for 37.8% of all pneumococcal isolates. Detection of PCV13 serotypes among ILI cases aged under 5 years declined significantly between 2015/16 and 2018/19.ConclusionsCommunity-based surveillance of S. pneumoniae among ILI cases complement surveillance at healthcare facilities to provide a more complete picture of pneumococcal carriage. Our findings contribute also to the growing body of evidence on the effects of PCV13 introduction on circulating serotypes and their potential replacement

    Luck perception is associated with less frequent preventive practices and a higher number of social contacts among adults during the SARS-CoV-2 pandemic

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    Objectives Non-pharmaceutical interventions have been crucial to reduce transmission of the SARS-CoV-2 virus in many countries including the United Kingdom. A key research priority has been to better understand psychological and social determinants of health behaviours. We aimed to quantify the impact of luck perception on contact and preventive behaviours among adults in the UK, adjusting for key confounders. Study design A cross-sectional study. Methods Data were collected between the 28th July and the 31st August 2020. Luck perception, which refers to a belief whether individual's SARS-CoV-2 infection status is determined by fate or chance, was measured using Chance score, drawing on Health Locus of Control Theory. Self-reporting online questionnaires were administered to obtain participants' contact patterns and frequencies of avoiding crowds, washed hands and wore a mask. Associations between luck perception and protective behaviours and contact patterns were quantified using regression models. Results Data from 233 survey respondents were analysed. Chance score was negatively associated with all protective behaviours; avoiding crowds (adjusted odds ratio (aOR) 0.46, 95% confidence interval (CI) 0.25–0.86, p = 0.02), washing hands (aOR 0.35, 95%CI 0.17–0.70, p = 0.003), and wearing masks (aOR 0.58, 95%CI 0.34–0.99, p = 0.046). For non-physical contacts (with or without distancing), a significant interaction was identified between Chance score and ethnicity. Chance score increased the number of non-physical contacts among white British, an opposite trend was observed for non-white participants. Conclusions Luck perception during the pandemic may affect individuals’ health protection behaviours and contact patterns. Further mechanistic understandings of human behaviours against infectious diseases are indispensable for effective response to future pandemics

    Contrasting reservoirs for Schistosoma japonicum between marshland and hilly regions in Anhui, China--a two-year longitudinal parasitological survey.

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    Schistosoma japonicum remains highly endemic in many counties in China and has recently re-emerged, to a large extent, in previously controlled areas. To test the hypothesis that small rodents and less agriculturally important domestic animals such as dogs and cats may play an important role in the transmission and potential re-emergence of this disease, an annual investigation of S. japonicum among humans, domestic animals and rodents, combined with detailed surveys of the snail intermediate host, was performed across 3 marshland villages and 3 hilly villages in Anhui province of China over 2 consecutive years. The highest infection prevalence and intensity observed across all mammals was in rodents in the hilly region; while in the marshland, bovines were suspected as the main reservoirs. However, relatively high infection prevalence levels were also found in dogs and cats in both regions. Such results may have implications for the current human- and bovine-oriented control policy for this medically and veterinarily important disease, particularly within the hilly regions of mainland China
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