Chikungunya virus (CHIKV) is currently one of the most relevant arboviruses to public health. It is a member of the Togaviridae family and alphavirus genus and causes an arthritogenic disease known as chikungunya fever (CHIKF). It is characterized by a multifaceted disease, which is distinguished fr...om other arbovirus infections by the intense and debilitating arthralgia that can last for months or years in some individuals. Despite the great social and economic burden caused by CHIKV infection, there is no vaccine or specific antiviral drugs currently available. Recent outbreaks have shown a change in the severity profile of the disease in which atypical and severe manifestation lead to hundreds of deaths, reinforcing the necessity to understand the replication and pathogenesis processes. CHIKF is a complex disease resultant from the infection of a plethora of cell types. Although there are several in vivo models for studying CHIKV infection, none of them reproduces integrally the disease signature observed in humans, which is a challenge for vaccine and drug development. Therefore, understanding the potentials and limitations of the state-of-the-art experimental models is imperative to advance in the field. In this context, the present review outlines the present knowledge on CHIKV epidemiology, replication, pathogenesis, and immunity and also brings a critical perspective on the current in vitro and in vivo state-of-the-art experimental models of CHIKF.
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In January 2021, the World Health Organization (WHO) published a new road map to address the burden of disease and death imposed by neglected tropical diseases (NTDs). The end of the first year of the 2021-2030 NTD road map is an opportunity to take stock of where we stand and how we plan to move fo...rward.
Considerable progress has been made since 2012 when the first road map was adopted. As of 6 June 2022, forty-six countries have eliminated at least one NTD, while 600 million people no longer require treatment because they are no longer exposed to risks associated with the pathogens that previously harmed them. In some cases, diseases that have plagued humanity for centuries, such as sleeping sickness and Guinea worm disease, are at an all-time low. Less tangible, but also important, there has been significant progress in the way NTDs are viewed. Additionally, the disruptive impact of the COVID-19 pandemic on NTD programmes is evident.
This brochure is the first in a series of advocacy briefs for the new NTD road map presenting highlights of success and challenges towards attaining the 2030 goals.
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The protozoan parasite Trypanosoma cruzi causes Chagas disease, an important public health problem throughout Latin America. Current therapeutic options are characterised by limited efficacy, long treatment regimens and frequent toxic side-effects. Advances in this area have been compromised by gaps... in our knowledge of disease pathogenesis, parasite biology and drug activity. Nevertheless, several factors have come together to create a more optimistic scenario. Drug-based research has become more systematic, with increased collaborations between the academic and commercial sectors, often within the framework of not-for-profit consortia. High-throughput screening of compound libraries is being widely applied, and new technical advances are helping to streamline the drug development pipeline. In addition, drug repurposing and optimisation of current treatment regimens, informed by laboratory research, are providing a basis for new clinical trials. Here, we will provide an overview of the current status of Chagas disease drug development, highlight those areas where progress can be expected, and describe how fundamental research is helping to underpin the process.
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En 1998, la Cinquante-et-Unième Assemblée mondiale de la Santé a adopté la résolution
WHA51.11 qui vise l’élimination mondiale du trachome en tant que problème de santé publique
à l’horizon 2020 (1). La stratégie recommandée pour atteindre cet objectif est récapitulée dans
le sig...le « CHANCE » qui signifie CHirurgie pour les personnes atteintes de trichiasis
trachomateux (TT – le dernier stade cécitant du trachome) ; Antibiothérapie, Nettoyage du
visage et Changements Environnementaux (2). Les interventions relatives aux volets A, N et CE
sont menées dans des districts entiers dans lesquels les cas de trachome évolutif
(inflammatoire) sont courants, dans le but de traiter les infections oculaires dues à Chlamydia
trachomatis, l’agent pathogène à l’origine du trachome, et de réduire durablement sa
transmission.
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L’orthopoxvirus simien ou virus de la variole du singe (MPXV), est un virus à ADN double brin qui appartient au genre Orthopoxvirus de la famille
des Poxviridés. Les poxvirus causent des maladies chez l’espèce humaine et beaucoup d’autres animaux ; l’infection se manifeste généralement... par la formation de lésions, de nodules cutanés ou d’une éruption cutanée disséminée. Les autres espèces d’orthopoxvirus (OPXV) pathogènes pour l’être humain comprennent le virus de la variole bovine et le virus variolique (responsable de la variole, qui a été éradiquée). Le virus de la vaccine est également un OPXV qui a été utilisé pour la vaccination humaine, et a été un outil essentiel pour l’éradication de la variole, obtenue en 1980. Le MPXV doit son nom au fait qu’il a été identifié pour la première fois chez le singe. Le MPXV se retrouve principalement chez les rongeurs, mais son réservoir reste indéterminé. Il existe deux clades connus du MPXV, l’un endémique en Afrique de l’Ouest, et l’autre dans la région du bassin du Congo.
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Most of the global burden of sepsis occurs in low- and middle-income countries (LMICs), but the prevalence and etiology of sepsis in LMICs are not well understood. In particular, the lack of laboratory infrastructure in many LMICs has historically precluded an assessment of the pathogens leading to ...sepsis. A recent systematic review found that data describing antimicrobial resistance were absent for 43% of countries in Africa, and only two countries have national antimicrobial resistance plans. In addition, small studies have identified indiscriminate antibiotic use both in and out of hospital settings in sub-Saharan Africa. The absence of microbiological data and lack of antibiotic stewardship complicate sepsis management and almost certainly worsens outcomes, particularly in low-resource systems. The purpose of this study was to examine the prevalence, etiology, and outcomes of sepsis among a cohort of critically ill patients in a referral hospital of Malawi, with a focus on the prevalence of culture-confirmed bacteremia and urinary tract infections.
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For thousands of years, humans have been using wildlife for commercial and subsistence purposes. Wildlife trade takes place at local, national and international levels, with different forms of wildlife, such as live animals, partly processed products and finished products. Wildlife is a vital source... of safe and nutritious food, clothing, medicine, and other products, in addition to having religious and cultural value. Wildlife trade also contributes to livelihoods, income generation and overall economic development.
However, wildlife trade can have detrimental effects on species conservation, depleting natural resources, impoverishing biodiversity and degrading ecosystems (Morton et al., 2021). Wildlife trade, whether legal or illegal, regulated or unregulated, can pose threats to animal health and welfare. It also presents opportunities for zoonotic pathogens to spill over between wildlife and domestic animals, and for diseases to emerge with serious consequences for public or animal health and profound economic impacts (IPBES, 2020; Swift et al., 2007; Smith et al., 2009; Gortazar et al., 2014; Stephen, 2021; Stephen et al., 2022; FAO, 2020). The risk of pathogen spillover and disease emergence is amplified with increased interaction between humans, wildlife and domestic animals. The risk of pathogen spillover has also been exacerbated by climate change, intensified agriculture and livestock production, deforestation, and other land-use changes. Wildlife trade is also a risk to ecosystem biodiversity via the introduction of invasive species (Wikramanayake et al., 2021). Therefore, increased effort must be put into understanding the potential consequences of the wildlife trade, mapping and analysing the adjacent risks, and implementing strategies to manage those risks. Reducing wildlife-trade risks not only helps to limit disease but also minimises the negative effects of invasive species. Between 1960 and 2021, invasive alien species caused estimated cumulative damage of around 116 billion euros across 39 countries in the European Union alone, despite strict import regulations (Haubrock et al., 2021). The effect of invasive species is extremely apparent.
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This review focusses on the interactions between the etiologic agent of Chagas disease, Trypanosoma cruzi, and its triatomine vector. The flagellate mainly colonizes the intestinal tract of the insect. The effect of triatomines on trypanosomes is indicated by susceptibility and refractoriness phenom...ena that vary according to the combination of the strains. Other effects are apparent in the different regions of the gut. In the stomach, the majority of ingested blood trypomastigotes are killed while the remaining transform to round stages. In the small intestine, these develop into epimastigotes, the main replicative stage. In the rectum, the population density is the highest and is where the infectious stage develops, the metacyclic trypomastigote. In all regions of the gut, starvation and feeding of the triatomine affect T. cruzi. In the small intestine and rectum, starvation reduces the population density and more spheromastigotes develop. In the rectum, feeding after short-term starvation induces metacyclogenesis and after long-term starvation the development of specific cells, containing several nuclei, kinetoplasts and flagella. When considering the effects of T. cruzi on triatomines, the flagellate seems to be of low pathogenicity. However, during stressful periods, which are normal in natural populations, effects occur often on the behaviour, eg, in readiness to approach the host, the period of time before defecation, dispersal and aggregation. In nymphs, the duration of the different instars and the mortality rates increase, but this seems to be induced by repeated infections or blood quality by the feeding on infected hosts. Starvation resistance is often reduced by infection. Longevity and reproduction of adults is reduced, but only after infection with some strains of T. cruzi. Only components of the surface coat of blood trypomastigotes induce an immune reaction. However, this seems to act against gut bacteria and favours the development of T. cruzi.
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As a high-burden neglected tropical disease, soil-transmitted helminth (STH) infections remain a major problem in the world, especially among children under five years of age. Since young children are at high risk of being infected, STH infection can have a long-term negative impact on their life, i...ncluding impaired growth and development. Stunting, a form of malnutrition in young children, has been long assumed as one of the risk factors in acquiring the STH infections. However, the studies on STH infection in children under five with stunting have been lacking, resulting in poor identification of the risk. Accordingly, we collected and reviewed existing related research articles to provide an overview of STH infection in a susceptible population of stunted children under five years of age in terms of prevalence and risk factors. There were 17 studies included in this review related to infection with Ascaris lumbricoides, Trichuris trichiura, hookworm, and Strongyloides stercoralis from various countries. The prevalence of STH infection in stunted children ranged from 12.5% to 56.5%. Increased inflammatory markers and intestinal microbiota dysbiosis might have increased the intensity of STH infection in stunted children that caused impairment in the immune system. While the age from 2 to 5 years along with poor hygiene and sanitation has shown to be the most common risk factors of STH infections in stunted children; currently there are no studies that show direct results of stunting as a risk factor for STH infection. While stunting itself may affect the pathogenesis of STH infection, further research on stunting as a risk factor for STH infection is encouraged.
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The Africa Centres for Disease Control and Prevention (Africa CDC) Biosafety and Biosecurity Initiative was launched by the Africa CDC in April 2019 with the aim of strengthening the African Union (AU) Member States’ biosafety and biosecurity systems and enabling them to comply with national and i...nternational requirements for biosafety and biosecurity including the International Health Regulations (IHR) (2005), the Biological Weapons Convention (BWC), and United Nations Security Council Resolution (UNSCR) 1540 and the multi-country Global Health Security Agenda (GHSA). The World Health Organization (WHO) Joint External Evaluation (JEE) and the Global Health Security Index report confirmed the known capacity gaps in biosafety and biosecurity among Africa Union Member (AU).
The regional consultations by Africa CDC conducted between 2019-2021 highlighted the deficiency or limited availability of standardized and regionally recognized training programs in the continent, limiting biosafety and biosecurity capacity building efforts in the region. In response, Africa CDC working with AU Member States developed a home grown, implementable and accessible professional training and certification program that is both recognized and endorsed by AU Member States. The Regional Training and Certification Program for Biosafety and Biosecurity Professionals, for African Biosafety and Biosecurity Professionals (RTCP-BBP) has four (4) areas of specialization, namely
Selection, Installation, Maintenance and Certification of Biological Safety Cabinets
Biorisk Management
Design and Maintenance of Facilities Handling High Risk Pathogens (Biocontainment Engineering)
Biological Waste management
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The Africa Centres for Disease Control and Prevention (Africa CDC) Biosafety and Biosecurity Initiative was launched by the Africa CDC in April 2019 with the aim of strengthening the African Union (AU) Member States’ biosafety and biosecurity systems and enabling them to comply with national and i...nternational requirements for biosafety and biosecurity including the International Health Regulations (IHR) (2005), the Biological Weapons Convention (BWC), and United Nations Security Council Resolution (UNSCR) 1540 and the multi-country Global Health Security Agenda (GHSA). The World Health Organization (WHO) Joint External Evaluation (JEE) and the Global Health Security Index report confirmed the known capacity gaps in biosafety and biosecurity among Africa Union Member (AU).
The regional consultations by Africa CDC conducted between 2019-2021 highlighted the deficiency or limited availability of standardized and regionally recognized training programs in the continent, limiting biosafety and biosecurity capacity building efforts in the region. In response, Africa CDC working with AU Member States developed a home grown, implementable and accessible professional training and certification program that is both recognized and endorsed by AU Member States. The Regional Training and Certification Program for Biosafety and Biosecurity Professionals, for African Biosafety and Biosecurity Professionals (RTCP-BBP) has four (4) areas of specialization, namely
- Selection, Installation, Maintenance and Certification of Biological Safety Cabinets
- Biorisk Management
- Design and Maintenance of Facilities Handling High Risk Pathogens (Biocontainment Engineering)
- Biological Waste management
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Environment International Volume 86, January 2016, Pages 14-23
Climate change refers to long-term shifts in weather conditions and patterns of extreme weather events. It may lead to changes in health threat to human beings, multiplying existing health problems. This review examines the scientific e...vidences on the impact of climate change on human infectious diseases. It identifies research progress and gaps on how human society may respond to, adapt to, and prepare for the related changes. Based on a survey of related publications between 1990 and 2015, the terms used for literature selection reflect three aspects — the components of infectious diseases, climate variables, and selected infectious diseases. Humans' vulnerability to the potential health impacts by climate change is evident in literature. As an active agent, human beings may control the related health effects that may be effectively controlled through adopting proactive measures, including better understanding of the climate change patterns and of the compound disease-specific health effects, and effective allocation of technologies and resources to promote healthy lifestyles and public awareness. The following adaptation measures are recommended: 1) to go beyond empirical observations of the association between climate change and infectious diseases and develop more scientific explanations, 2) to improve the prediction of spatial–temporal process of climate change and the associated shifts in infectious diseases at various spatial and temporal scales, and 3) to establish locally effective early warning systems for the health effects of predicated climate change.
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Buruli ulcer (BU) is a bacterial skin infection that is caused by Mycobacterium ulcerans and mainly affects people who reside in the rural areas of Africa and in suburban and beach resort communities in Australia.
The purpose of this document is to provide interim guidance to laboratories and stakeholders involved in laboratory testing of patients who meet the definition of suspected case of pneumonia associated with a novel coronavirus identified in Wuhan, China.
19 March 2020
For COVID-19, as for many infectious diseases, the true level of transmission is frequently underestimated because a substantial proportion of people with the infection are undetected either because they are asymptomatic or have only mild symptoms and thus typically fail to present at healthcare fac...ilities. There may also be neglected or under-served segments of the population who are less likely to access healthcare or testing. Under-detection of cases may be exacerbated during an epidemic, when testing capacity may be limited and restricted to people with severe cases and priority risk groups (such as frontline healthcare workers, elderly people and people with comorbidities). Cases may also be misdiagnosed and attributed to other diseases with similar clinical presentation, such as influenza.
Differences in mortality between groups of people and countries are important proxy indicators of relative risk of death that guide policy decisions regarding scarce medical resource allocation during the ongoing COVID-19 pandemic. This document is intended to help countries estimate CFR and, if possible, IFR, as appropriately and accurately as possible, while accounting for possible biases in their estimation
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