Background: The human helminth infections include ascariasis, trichuriasis, hookworm infections, schistosomiasis, lymphatic filariasis (LF) and onchocerciasis. It is estimated that almost 2 billion people worldwide are infected with helminths. Whilst the WHO treatment guidelines for helminth infecti...ons are mostly aimed at controlling morbidity, there has been a recent shift with some countries moving towards goals of disease elimination through mass drug administration, especially for LF and onchocerciasis. However, as prevalence is driven lower, treating entire populations may no longer be the most efficient or cost-effective strategy. Instead, it may be beneficial to identify individuals or demographic groups who are persistently infected, often termed as being “predisposed” to infection, and target treatment at them.
Methods: The authors searched Embase, MEDLINE, Global Health, and Web of Science for all English language, humanbased papers investigating predisposition to helminth infections published up to October 31st, 2017. The varying definitions used to describe predisposition, and the statistical tests used to determine its presence, are summarised. Evidence for predisposition is presented, stratified by helminth species, and risk factors for predisposition to infection are identified and discussed.
Results: In total, 43 papers were identified, summarising results from 34 different studies in 23 countries. Consistent evidence of predisposition to infection with certain species of human helminth was identified. Children were regularly found to experience greater predisposition to Ascaris lumbricoides, Schistosoma mansoni and S. haematobium than adults. Females were found to be more predisposed to A. lumbricoides infection than were males. Household clustering of infection was identified for A. lumbricoides, T. trichiura and S. japonicum. Ascaris lumbricoides and T. trichiura also showed evidence of familial predisposition. Whilst strong evidence for predisposition to hookworm infection was identified, findings with regards to which groups were affected were considerably more varied than for other helminth species.
Conclusion: This review has found consistent evidence of predisposition to heavy (and light) infection for certain human helminth species. However, further research is needed to identify reasons for the reported differences between demographic groups. Molecular epidemiological methods associated with whole genome sequencing to determine ‘who infects whom’ may shed more light on the factors generating predisposition.
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Leptospirosis, a spirochaetal zoonosis, occurs in diverse epidemiological settings and affects vulnerable populations, such as rural subsistence farmers and urban slum dwellers. Although leptospirosis is a life-threatening disease and recognized as an important cause of pulmonary haemorrhage syndrom...e, the lack of global estimates for morbidity and mortality has contributed to its neglected disease status
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Parasites & Vectors volume 11, Article number: 264 (2018)
Dengue creates a staggering epidemiological and economic burden for endemic countries. Without a specific therapy and with a commercial vaccine that presents some problems relative to its full effectiveness, initiatives to improve vector... control strategies, early disease diagnostics and the development of vaccines and antiviral drugs are priorities. In this study, we present the probable origins of dengue in America and the trajectories of its spread. Overall, dengue diagnostics are costly, making the monitoring of dengue epidemiology more difficult and affecting physicians’ therapeutic decisions regarding dengue patients, especially in developing countries. This review also highlights some recent and important findings regarding dengue in Brazil and the Americas. We also summarize the existing DENV polymerase chain reaction (PCR) diagnostic tests to provide an improved reference since these tests are useful and accurate at discriminating DENV from other flaviviruses that co-circulate in the Americas. Additionally, these DENV PCR assays ensure virus serotyping, enabling epidemiologic monitoring.
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Objective: To review research on associations of trauma type with PTSD in the WHO World Mental Health (WMH) surveys, a series of epidemiological surveys that obtained representative data on trauma-specific PTSD.
Carlos Chagas discovered American trypanosomiasis, also named Chagas disease (CD) in his honor, just over a century ago. He described the clinical aspects of the disease, characterized by its etiological agent (Trypanosoma cruzi) and identified its insect vector. Initially, CD occurred only in Latin... America and was considered a silent and poorly visible disease. More recently, CD became a neglected worldwide disease with a high morbimortality rate and substantial social impact, emerging as a significant public health threat. In this context, it is crucial to better understand better the epidemiological scenarios of CD and its transmission dynamics, involving people infected and at risk of infection, diversity of the parasite, vector species, and T. cruzi reservoirs. Although efforts have been made by endemic and non-endemic countries to control, treat, and interrupt disease transmission, the cure or complete eradication of CD are still topics of great concern and require global attention. Considering the current scenario of CD, also affecting non-endemic places such as Canada, USA, Europe, Australia, and Japan, in this review we aim to describe the spread of CD cases worldwide since its discovery until it has become a global public health concern.
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The objective of this paper is to summarise and critically review the available data about onchocerciasis in Mozambique, in order to report epidemiological and clinical aspects related to the disease and identify gaps in knowledge. The paper is intended to raise awareness of the existence and import...ance of this disease and to define research priorities
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DIAGNOSING PTSD IN CHILDHOOD | The following literature review addresses the developmental and domain-specific consequences of previous and current diagnostic criteria for posttraumatic stress disorder (PTSD) in pre-adolescent children. PTSD was introduced in 1980 to capture extreme responses follow...ing a traumatic event. I analyze the evolution of the disorder’s diagnostic criteria toward a more developmentally conscious structure. I also examine instances in which these criteria lack developmental consistency: (1) preschool PTSD is the only diagnostic subtype despite the fact that childhood development also differentiates traumatic expressions in older children from adolescents and adults; and (2) many of the PTSD epidemiological data that have been reanalyzed under the most recent (DSM-5) typology only refer to adolescent and adult samples although many researchers have
demonstrated that developmental alterations to DSM-IV and DSM-IV-TR criteria produce significantly higher prevalence rates in children.
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Proc Natl Acad Sci U S A v.110(21); 2013 May 21 PMC3666729 ;
A systematic review was conducted by a multidisciplinary team to analyze qualitatively best available scientific evidence on the effect of agricultural intensification and environmental changes on the risk of zoonoses for which there are... epidemiological interactions between wildlife and livestock.
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Chagas disease caused by Trypanosoma cruzi is a public health issue in Latin America. This highly diverse parasite is divided into at least seven discrete typing units (DTUs) TcI-TcVI and Tcbat. Some DTUs have been associated with geographical distribution in epidemiological scenarios and clinical m...anifestations, but these aspects remain poorly understood. Many studies have focused on studying the parasite and its vectors/hosts, using a wide variety of genetic markers and methods. Here, we performed a systematic review of the literature for the last 20 years to present an update of DTUs distribution in the Americas, collecting ecoepidemiological information. We found that the DTUs are widespread across the continent and that there is a whole gamma of genetic markers used for the identification and genotyping of the parasite. The data obtained in this descriptor could improve the molecular epidemiology studies of Chagas disease in endemic regions.
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This report on progress achieved in the WHO European Region and Member States in implementing the European food and nutrition action plan 2015–2020 presents selected epidemiological data on the nutritional status of populations throughout the Region and on implementation of policies recommended in... regional and global frameworks to promote healthy nutrition and prevent obesity. The data contained in the report are derived from the responses of Member States to the WHO Global nutrition policy review questionnaire.
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The Leprosy Programme and Transmission Assessment (LPTA) is an activity that is carried out by internal teams towards the end of Phase 1 (see Leprosy Elimination Framework in the Annex) when a subnational jurisdiction (typically second-tier) reaches the milestone for interruption of transmission, i....e., zero autochthonous child cases for a consecutive period of five years. It also needs to be done at the end of Phase 2, when the second milestone of elimination of leprosy disease has been reached. An LPTA will be carried out to document that all relevant programme criteria have been met and examine trends of epidemiological indicators in such jurisdiction to confirm that the milestone has been achieved. The LPTA includes assessment of health facilities that provide leprosy services. LPTA comprises of review of epidemiological data, health facility assessment and data validation and verification of the programme criteria through observation during a field visit. The evidence collected in this way in subnational health administrative units is compiled in a Leprosy Elimination Dossier to be submitted to WHO when the country reaches the milestone for elimination of disease in the country as whole. Countries that have not detected any new leprosy cases in the past three years or more can use the LPTA at national level prior to or as part of the verification process. Countries likely to be among the first to apply for verification may have had no new cases detected for more than 10 years.
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The Leprosy Programme and Transmission Assessment (LPTA) is an activity that is carried out by internal teams towards the end of Phase 1 (see Leprosy Elimination Framework in the Annex) when a subnational jurisdiction (typically second-tier) reaches the milestone for interruption of transmission, i....e., zero autochthonous child cases for a consecutive period of five years. It also needs to be done at the end of Phase 2, when the second milestone of elimination of leprosy disease has been reached. An LPTA will be carried out to document that all relevant programme criteria have been met and examine trends of epidemiological indicators in such jurisdiction to confirm that the milestone has been achieved. The LPTA includes assessment of health facilities that provide leprosy services. LPTA comprises of review of epidemiological data, health facility assessment and data validation and verification of the programme criteria through observation during a field visit. The evidence collected in this way in subnational health administrative units is compiled in a Leprosy Elimination Dossier to be submitted to WHO when the country reaches the milestone for elimination of disease in the country as whole. Countries that have not detected any new leprosy cases in the past three years or more can use the LPTA at national level prior to or as part of the verification process. Countries likely to be among the first to apply for verification may have had no new cases detected for more than 10 years.
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The objective of this concept note and the framework it outlines is the elimination of a group of CDs and the negative health effects they generate, which together create a tangible burden on affected individuals, their families and communities, and on health care systems throughout the Region. Thou...gh there is no unified consensus on the best measures to use for the public’s health and a nation’s epidemiologic situation, it is common for the disease burden to be measured by disease rates (incidence, prevalence, etc.), disease-specific death rates, comparative morbidity and mortality rates, geographic distribution, and disability-adjusted life years (DALYs). The current epidemiological situation, including data on disease rates or geographic distribution for the diseases in Table 1, is discussed below in Section 4. Hotez et al. (2008) were the first to review and compare the burden of DALYs in Latin America and the Caribbean—for NTDs, HIV/AIDS, malaria, and TB—as it existed about 10 years ago. Though the regional burden of TB, malaria, and neglected infectious diseases (NIDs) is somewhat less than it was 10 years ago, work (and schooling) continue to be lost to illness and premature death or disability, and the need for stepping up disease elimination efforts is evident in all communities living in vulnerable conditions....
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PLOS One November 20, 2020 https://doi.org/10.1371/journal.pone.0241799 . The first autochthonous case of chikungunya virus (CHIKV) infection in Brazil was in September 2014 in the State of Amapá, and from there it rapidly spread across the country. The present study was conducted in 2016 in the st...ate of Rio Grande do Norte, and the aims were to describe the epidemiological and the clinical aspects of the CHIKV outbreak.
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Gambiense human African trypanosomiasis is a deadly infectious disease affecting West and Central Africa, South Sudan and Uganda, and transmitted between humans by tsetse flies. The disease has caused several major epidemics, the latest one in the 1990s. Thanks to recent innovations such as rapid di...agnostic tests for population screening, a single-dose oral treatment and a highly efficient vector control strategy, interruption of transmission of the causative parasite is now within reach. If indeed gHAT has an exclusively human reservoir, this could even result in eradication of the disease. Even if there were an animal reservoir, on the basis of epidemiological data, it plays a limited role. Maintaining adequate postelimination surveillance in known historic foci, using the newly developed tools, should be sufficient to prevent any future resurgence.
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- Module 1: Understanding modelling approaches for sexual, reproductive, maternal, newborn, child and adolescent health, and nutrition
Coronavirus disease 2019 (COVID-19) has a wide range of documented effects. It directly causes death and disability for some people infected. However, disruption to... essential health services, resources allocated to mitigation and therefore away from essential health service delivery, and the overall impact on the economy and society must also be considered within the response to COVID-19. Understanding the magnitude of all of these effects is an essential part of developing mitigation polices.
Several epidemiological models have been created to assess the potential impact of disruptions to essential health services caused by COVID-19 on morbidity and mortality from conditions other than COVID-19 illness. This guide presents models that have been used to assess these indirect impacts. The effects have been studied in various settings, using a variety of models.
The guide is intended for people who need to understand what the models say, their construction and their underlying assumptions, or need to use models and their outcomes for planning and programme development and to support policy decisions for a country or region.
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