April 2022 Volume 35 Issue 2 e00152-21
Population movements have turned Chagas disease (CD) into a global public health problem. Despite the successful implementation of subregional initiatives to control vectorial and transfusional Trypanosoma cruzi tra...nsmission in Latin American settings where the disease is endemic, congenital CD (cCD) remains a significant challenge. In countries where the disease is not endemic, vertical transmission plays a key role in CD expansion and is the main focus of its control. Although several health organizations provide general protocols for cCD control, its management in each geopolitical region depends on local authorities, which has resulted in a multitude of approaches. The aims of this review are to (i) describe the current global situation in CD management, with emphasis on congenital infection, and (ii) summarize the spectrum of available strategies, both official and unofficial, for cCD prevention and control in countries of endemicity and nonendemicity. From an economic point of view, the early detection and treatment of cCD are cost-effective. However, in countries where the disease is not endemic, national health policies for cCD control are nonexistent, and official regional protocols are scarce and restricted to Europe. Countries of endemicity have more protocols in place, but the implementation of diagnostic methods is hampered by economic constraints. Moreover, most protocols in both countries where the disease is endemic and those where it is not endemic have yet to incorporate recently developed technologies. The wide methodological diversity in cCD diagnostic algorithms reflects the lack of a consensus. This review may represent a first step toward the development of a common strategy, which will require the collaboration of health organizations, governments, and experts in the field.
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BMJ Glob Health 2017;2:e000345. doi:10.1136/bmjgh-2017-000345. WHO's 2020 milestones for Chagas disease include having all endemic Latin American countries certified with no intradomiciliary Trypanosoma cruzi transmission, and infected patients unde...r care. Evaluating the variation in historical exposure to infection is crucial for assessing progress and for understanding the priorities to achieve these milestones.
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Chagas disease is a zoonosis caused by the protozoa Trypanosoma cruzi. It is transmitted to humans by contact of triatomine bug faeces with a break in the skin (often caused by a bite from the triatomine bug), or with mucous membranes. Transmission ...by contaminated blood transfusion, accidental exposure to blood, mother-to-child (during pregnancy or childbirth) or consumption of contaminated food and water is also possible.
Chagas disease has two phases: an acute phase, which lasts approximately 4 to 6 weeks, and a chronic phase, which is lifelong if left untreated.
The disease is primarily found on the American continent. It is significantly underdiagnosed.
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Schistosomiasis is widely recognized as a disease that is socially determined. An understanding of the social and behavioural factors linked to disease transmission and control should play a vital role in designing policies and strategies for schist...osomiasis prevention and control. To this must be added the awareness that schistosomiasis is also a disease of poverty. It still survives in poverty-stricken, remote areas where there is little or no safe water or sanitation, and health care is scarce or non-existent. For a variety of complex reasons, many of which are addressed in this book, the disease is particularly prevalent in sub-Saharan Africa, and persists in certain areas of rural China. This concern for human behaviour in an environment of poverty echoes the concerns of the new research priority for “diseases of poverty” identified by the Special Programme for Research & Training in Tropical Diseases.
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Schistosomiasis is a neglected tropical disease of global medical and veterinary importance. As efforts to eliminate schistosomiasis as a public health problem and interrupt transmission gather momentum, the potential zoonotic risk posed by livestoc...k Schistosoma species via viable hybridisation in sub-Saharan Africa have been largely overlooked. We aimed to investigate the prevalence, distribution, and multi-host, multiparasite transmission cycle of Haematobium group schistosomiasis in Senegal, West Africa.
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Les progrès remarquables réalisés dans la lutte contre la forme à T. b. gambiense reposent sur le dépistage et le traitement curatif, une stratégie qui interrompt la transmission en réduisant le réservoir de parasites chez l’être humain. ...Parfois, cette
approche a été combinée avec des activités de lutte antivectorielle. L’objet de ces lignes directrices est donc de la plus haute importance pour la poursuite des progrès en vue de l’élimination de la THA.
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Sleeping sickness is a neglected tropical disease affecting rural communities in sub-Saharan Africa. The reduction in the number of reported cases in recent years indicates that disease transmission is under control. However, many aspects of patient... management still need to be improved. Undiagnosed patients or inappropriate treatment due to an incorrect determination of the disease stage could in fact lead to its re-emergence. There is thus a strong need for new diagnostic and staging tools to keep the disease under control and to improve the clinical care of patients. This review describes the most promising biomarkers proposed so far for the diagnosis and stage determination of patients suffering from sleeping sickness, with a particular emphasis on their translation into diagnostic tools for field applications.
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Goal and objectives of the guideline
The goal of this guideline is to provide evidence-based recommendations to countries in their efforts to accomplish schistosomiasis morbidity control and elimination as a public health problem, and to move towards interruption of ...ght medbox">transmission.
The recommendations contained herein will help countries to implement national schistosomiasis control and elimination programmes and support efforts to verify the interruption of transmission.
The specific objectives are to provide guidance on:
prevalence thresholds, target age groups and frequency of preventive chemotherapy for schistosomiasis;
establishment of water, sanitation and hygiene (WASH) and snail control activities to support control and elimination of schistosomiasis;
use of diagnostic tests in humans in low transmission areas and for moving to, and evaluating the interruption of transmission of schistosomiasis;
tools for the assessment of Schistosoma spp. infection in snail hosts; and
diagnostic tests for the assessment of schistosomiasis infection in animal reservoirs of infection
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Sleeping sickness is controlled by case detection and treatment but this often only reaches less than 75% of the population. Vector control is capable of completely interrupting HAT transmission but is not used because of expense. We conducted a ful...l scale field trial of a refined vector control technology. From preliminary trials we determined the number of insecticidal tiny targets required to control tsetse populations by more than 90%. We then carried out a full scale, 500 km2 field trial covering two HAT foci in Northern Uganda (overall target density 5.7/km2). In 12 months tsetse populations declined by more than 90%. A mathematical model suggested that a 72% reduction in tsetse population is required to stop transmission in those settings. The Ugandan census suggests population density in the HAT foci is approximately 500 per km2. The estimated cost for a single round of active case detection (excluding treatment), covering 80% of the population, is US$433,333 (WHO figures). One year of vector control organised within country, which can completely stop HAT transmission, would cost US$42,700. The case for adding this new method of vector control to case detection and treatment is strong. We outline how such a component could be organised.
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Leishmaniasis is a vector-borne disease with a wide variety of parasite species, reservoirs, and vectors involved in transmission. It is caused by different species of the protozoa Leishmania and is transmitted to animals and humans through a bite o...f insects in the Psychodidae family. Its presence is directly linked to poverty, but social, environmental, and climatalogic factors directly influence the disease's epidemiology.
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Leptospirosis is a zoonotic disease with epidemic potential, especially after a heavy rainfall,
caused by a bacterium called Leptospira. Leptospira interrogans is pathogenic to humans and
animals, with more than 200 serologic variants or serovars. Humans usually acquire
leptospirosis through dire...ct contact with the urine of infected animals or a urine-contaminated
environment. Human-to-human transmission occurs only very rarely. Leptospirosis may present
with a wide variety of clinical manifestations, from a mild illness that may progress to a serious
and sometimes fatal disease. Its symptoms may mimic many diseases, such as influenza,
dengue and other viral haemorrhagic diseases; making the correct diagnosis (clinical and
laboratory) at the onset of symptoms is important to prevent severe cases and save lives,
primarily in outbreak situations.
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Leptospirosis is an infectious disease caused by pathogenic organisms belonging to the genus Leptospira, that are transmitted directly or indirectly from animals to humans. Leptospirosis is a major direct zoonosis. Humanto-human transmission occurs ...only very rarely.
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Les présentes lignes directrices ont pour objet de préparer les pays d’endémie à arrêter l’AMM à l’issue du traitement, à passer à la surveillance post-thérapeutique ainsi qu’à confirmer l’interruption de la transmission à l’i...ssue de la phase 2 et à débuter la surveillance post-élimination.
Le but est de fournir un outil actualisé pour atteindre et vérifier l’élimination de la
transmission d’Ovolvulus à l’issue des programmes d’élimination de l’onchocercose qui utilisent principalement l’AMM.
Les objectifs sont de :
• formuler des recommandations basées sur des preuves à l’intention des prestataires de soins et des décideurs en matière de politique pour démontrer et confirmer l’interruption de la transmission d’O. volvulus avant, pendant et après la surveillance post-thérapeutique ;
• informer les utilisateurs finaux des procédures nécessaires pour vérifier l’élimination de l’onchocercose humaine.
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Schistosomiasis is widely recognized as a disease that is socially determined. An
understanding of the social and behavioural factors linked to disease transmission and
control should play a vital role in designing policies and strategies for schi...stosomiasis
prevention and control. To this must be added the awareness that schistosomiasis is
also a disease of poverty. It still survives in poverty-stricken, remote areas where there
is little or no safe water or sanitation, and health care is scarce or non-existent. For
a variety of complex reasons, many of which are addressed in this book, the disease
is particularly prevalent in sub-Saharan Africa, and persists in certain areas of rural
China. This concern for human behaviour in an environment of poverty echoes the
concerns of the new research priority for “diseases of poverty” identified by the
Special Programme for Research & Training in Tropical Diseases.
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The incubation period (the time the virus spreads from the peripheral nerves near the site of the bite via the spinal cord to the brain – see transmission and pathogenesis) ranges in general between 2 and 3 month (2 weeks to 6 years are reported) ...depending on the site of infliction, the amount of virus and the virus strain. Due to its neurotropism all known lyssaviruses cause severe neurological symptoms as a result of an acute encephalitis. Therefore, clinical signs in humans and animals are very similar.
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Chagas disease (American trypanosomiasis) is endemic in 21 countries of the Americas, where control is largely focused on elimination of the domestic insect vectors (Triatominae) coupled with measures to extend and improve the screening of blood donors in order to avoid tranfusional ...ribute-to-highlight medbox">transmission. Through national programmes and multinational initiatives coordinated by WHO-PAHO, much has been accomplished in these domains in terms of reducing transmission. Attention now turns to consolidating the successes in interrupting transmission, and improved treatment for those already infected and those who may become affected in the future. This article, based on technical discussions at the "Epidemiological and Sociological Determinants of Chagas Disease, Basic Information to Establish a Surveillance and Control Policy " meeting in Rio de Janeiro, is designed to open the debate on appropriate strategies for continuation of the successful initiatives against Chagas disease.
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Leishmaniasis is a vector-borne disease with a wide variety of parasite species, reservoirs, and vectors involved in transmission. It is caused by different species of the protozoa Leishmania and is transmitted to animals and humans through a bite o...f insects in the Psychodidae family. Its presence is directly linked to poverty, but social, environmental, and climatalogic factors directly influence the disease's epidemiology.
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We developed an integrated vector surveillance (IVS) proposal for cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL) in the Americas, based on eco-epidemiological studies conducted by researchers of the Leishmaniasis Research Network of Argentina. For CL, the ...light medbox">transmission was explained in the framework of the edge effect, the increase of vectors and risk of exposure at ecotones and environmental interfaces, and typified as ephemeral, transient, or permanent edges, supporting a cost-effective IVS strategy for early warning of CL outbreaks through an environmental modification alert network, which includes multiple sources of information and actors. In relation to VL, the earliest colonization sites and spatial distribution were explained by modeling and forecasting the most likely hotspots, persistent in time and space, and modulated by environmental variables. Therefore, for VL, a scalar strategy of critical site selection is proposed from a “city” scale based on secondary sources such as remote sensing for the definition of possible areas to monitor and intervene, a scale of restriction from possible to most likely areas through local knowledge, and a “focal site” scale of trap placement through field observation; in this way, IVS activities are carried out at a few sites of the urban landscape and allow a sustainable program.
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Infection prevention and control (IPC) in a CTC/ CTU IPC are all practical measures taken in the healthcare facility to prevent harm caused by infections to patients, health workers and communities.
The main goal of IPC in the cholera response is to
• To reduce ...light medbox">transmission of health care-associated infections of cholera and any other infectious disease
• To enhance the safety of staff, patients and visitors
• To enhance the ability of the organization/health care facility to respond to an outbreak
• To reduce the risk of the hospital (health care facility) itself amplifying the outbreak
Water, Sanitation and Hygiene (WASH)
WASH are all measures taken to guarantee environmental hygiene, safe water of all used within the health facility. It encompasses water, sanitation, waste management, cleaning within the health facility which in this case is CTU/C. A complete WASH package in the CTU/CTC reduces the risk of spread of Vibrio cholerae inside and outside the CTC/CTU.
The probability of spreading or acquiring cholera through a CTC/CTU can be highly reduced when proper IPC and WASH measures are respected, followed and monitored. These measures are, in principle, valid in CTC/CTUs and ORPs, although they need to be adapted to the specific characteristics of the facility concerned.
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This publication describes the history of malaria in Uzbekistan. It evaluates the policies and strategies applied after the re-establishment of local transmission to contain malaria outbreaks in the 1990s and early 2000s, and highlights the interven...tions subsequently used to eliminate malaria in the country. Uzbekistan was officially certified by WHO as a malaria-free country in 2018. Lessons for countries embarking upon elimination are distilled. The publication is intended for health managers and personnel, researchers, teachers, students and post-graduates at medical schools.
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