Research and Reports in Tropical Medicine 2021:12 63–76 . This review focusses on the interactions between the etiologic agent of Chagas disease, Trypanosoma cruzi, and its triatomine vector.
Yaws forms part of a group of chronic bacterial infections commonly known as the endemic treponematoses. These diseases are caused by spiral bacteria of the genus Treponema, which also includes endemic syphilis (bejel) and pinta. Yaws is the most common of these three infections.
La filariasis linfática, conocida generalmente como elefantiasis, es una enfermedad tropical desatendida. La infección humana se produce por la transmisión de unos parásitos denominados filarias a través de los mosquitos. La infección se contrae generalmente en la infancia y provoca daños no ...manifiestos en el sistema linfático.
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Rabies is a fatal viral disease, but is preventable in humans. The rabies virus is transmitted to humans through virus-laden saliva from a rabid animal, mostly dogs. The virus is shed in the saliva of an infected animal and can be introduced into another body through bites, scratches and any other ...wounds that transect the skin. Contact of the infected saliva with mucous membranes is also thought to be a possible route of infection, whereas contact of infected saliva with intact skin is not considered an exposure. Rabies is preventable through pre-exposure prophylaxis (PrEP) for individuals at high and continual risk, and post-exposure prophylaxis (PEP).
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About six to seven million people worldwide, mostly in Latin America, are estimated to be infected with
Trypanosoma cruzi, the parasite that causes Chagas disease (WHO data from 2021). Chagas disease is
found mainly in endemic areas of 21 Latin American countries.
Chikungunya: WHO fact sheet on Chikungunya providing key facts and information on scope of the problem, who is at risk, prevention, WHO response.
Scabies is a contagious skin condition caused by the mite Sarcoptes scabiei which burrows into the skin and causes severe itching. Scabies is transmitted by direct skin-to-skin contact or indirectly by contact with contaminated material (fomites). This condition is often challenging to diagnose as m...any patients may have only subtle symptoms. However, other patients may present with the classic history of exposure, severe pruritis that is worse at night, and reference to other individuals with similar symptoms. This activity reviews the evaluation and treatment of scabies and highlights the role of the interprofessional team in managing patients with this condition.
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Rabies is a fatal zoonotic disease most often transmitted to people via bites from infected dogs. This course provides a general introduction to rabies, and the One Health approach currently taken to prevent it. It consists of seven video-lectures, demonstration videos, and lessons learnt from peopl...e who work at the frontline of rabies elimination programmes around the world. It targets both a general audience and those who would like to learn more about rabies and the pathway to eliminating this disease – like prospective and current public health and animal health practitioners in rabies endemic countries.
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Soil transmitted helminth (STH) infections are among the most common human infections worldwide with over 1 billion people affected. Many estimates of STH infection are often based on school-aged children (SAC). This study produced predictive risk-maps of STH on a more finite scale, estimated the nu...mber of people infected, and the amount of drug required for preventive chemotherapy (PC) in Ogun state, Nigeria. Georeferenced STH infection data obtained from a cross-sectional survey at 33 locations between July 2016 and November 2018, together with remotely-sensed environmental and socio-economic data were analyzed using Bayesian geostatistical modelling. Stepwise variable selection procedure was employed to select a parsimonious set of predictors to predict risk and spatial distribution of STH infections. The number of persons (pre-school ages children, SAC and adults) infected with STH were estimated, with the amount of tablets needed for preventive chemotherapy. An overall prevalence of 17.2% (95% CI 14.9, 19.5) was recorded for any STH infection. Ascaris lumbricoides infections was the most predominant, with an overall prevalence of 13.6% (95% CI 11.5, 15.7), while Hookworm and Trichuris trichiura had overall prevalence of 4.6% (95% CI 3.3, 5.9) and 1.7% (95% CI 0.9, 2.4), respectively. The model-based prevalence predictions ranged from 5.0 to 23.8% for Ascaris lumbricoides, from 2.0 to 14.5% for hookworms, and from 0.1 to 5.7% for Trichuris trichiura across the implementation units. The predictive maps revealed a spatial pattern of high risk in the central, western and on the border of Republic of Benin. The model identified soil pH, soil moisture and elevation as the main predictors of infection for A. lumbricoides, Hookworms and T. trichiura respectively. About 50% (10/20) of the implementation units require biannual rounds of mass drug administration. Approximately, a total of 1.1 million persons were infected and require 7.8 million doses. However, a sub-total of 375,374 SAC were estimated to be infected, requiring 2.7 million doses. Our predictive risk maps and estimated PC needs provide useful information for the elimination of STH, either for resource acquisition or identifying priority areas for delivery of interventions in Ogun State, Nigeria.
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La enfermedad de Chagas, también conocida como tripanosomiasis americana, es causada por el parásito Trypanosoma cruzi. La forma más común de contraer la infección es a través del contacto con las heces de un insecto triatominio (conocido con los nombres de chinche besucona, benchuca, vinchuca..., chipo o barbeiro), el cual se alimenta de la sangre de seres humanos y animales.
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Trachoma is one of oldest infectious diseases known to humans. It is caused by the bacteria Chlamydia trachomatis, which is transmitted through contact with eye secretions of infected people (shared use of towels and handkerchiefs, contact with fingers, etc.), as well by flies that help spread it.
Chagas disease is found mainly in endemic areas of 21 continental Latin American countries. The most common way people are infected with Chagas is through the blood-sucking triatomine bugs, also known as ‘kissing bugs’ (or vinchuca, barbeiro, pito, chinche, chipo in different Latin American coun...tries). The bugs typically live in wall or roof cracks of poorly constructed homes made of materials such as mud, straw and palm thatch. They come out at night to feed on people’s blood while they’re sleeping, then defecate close to the bite. Their faeces contain the parasite, which can then enter the person’s body when they inadvertently smear the bug’s waste into the bite or another skin break, the eyes or the mouth.
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Rabies is a virus (Lyssavirus) that infects cells in the central nervous
system, causing disease in the brain and, ultimately, death. Any animal
with rabies has the ability to transmit the disease to humans or other
animals.
There is no cure for rabies, but it is 100 percent preventable through
...
prompt, appropriate medical care.
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There is no cure for rabies, but it is 100 percent preventable through prompt, appropriate medical care. Every year hundreds of South Carolinians must undergo preventive treatment for rabies due to exposure to a rabid or suspected rabid animal. Although the cost varies, post-exposure treatment typic...ally exceeds $8,000 per person.
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Am. J. Trop. Med. Hyg., 106 (Suppl 5), 2022, pp. 56–60. Lymphatic filariasis (LF) is a parasitic disease that is a major cause of chronic disability in the developing world. According to the 2021–2030 road map for neglected tropical diseases (NTDs) published by the World Health Organization (WHO...), the global goal for LF is elimination as a public health problem by 2030 through repeated rounds of mass drug administration (MDA). Critical components of any elimination program are monitoring and surveillance. Appropriate assessment tools and methods are needed for each stage of an elimination program; mapping to identify which areas require intervention, monitoring to assess the impact of interventions, and post-intervention surveillance to validate elimination or detect recrudescence.
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Rabies is a viral zoonotic disease that causes progressive and fatal inflammation of the brain and spinal cord. Clinically, it has two forms:
Furious rabies – characterized by hyperactivity and hallucinations.
Paralytic rabies – characterized by paralysis and coma.
Dengue is a mosquito-borne viral disease that has rapidly spread to all regions of WHO in recent years. Dengue virus is transmitted by female mosquitoes mainly of the species Aedes aegypti and, to a lesser extent, Ae. albopictus. These mosquitoes are also vectors of chikungunya, yellow fever and Zik...a viruses. Dengue is widespread throughout the tropics, with local variations in risk influenced by climate parameters as well as social and environmental factors.
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After 100 years of chemotherapy with impractical and toxic drugs, an oral cure for human African trypanosomiasis (HAT) is available: Fexinidazole. In this case, we review the history of drug discovery for HAT with special emphasis on the discovery, pre-clinical development, and operational challenge...s of the clinical trials of fexinidazole. The screening of the Drugs for Neglected Diseases initiative (DNDi) HAT-library by the Swiss TPH had singled out fexinidazole, originally developed by Hoechst (now Sanofi), as the most promising of a series of over 800 nitroimidazoles and related molecules. In cell culture, fexinidazole has an IC50 of around 1 µM against Trypanosoma brucei and is more than 100-fold less toxic to mammalian cells. In the mouse model, fexinidazole cures both the first, haemolymphatic, and the second, meningoencephalitic stage of the infection, the latter at 100 mg/kg twice daily for 5 days. In patients, the clinical trials managed by DNDi and supported by Swiss TPH mainly conducted in the Democratic Republic of the Congo demonstrated that oral fexinidazole is safe and effective for use against first- and early second-stage sleeping sickness. Based on the positive opinion issued by the European Medicines Agency in 2018, the WHO has released new interim guidelines for the treatment of HAT including fexinidazole as the new therapy for first-stage and non-severe second-stage sleeping sickness caused by Trypanosoma brucei gambiense (gHAT). This greatly facilitates the diagnosis and treatment algorithm for gHAT, increasing the attainable coverage and paving the way towards the envisaged goal of zero transmission by 2030.
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El dengue es una enfermedad vírica transmitida por mosquitos que en los últimos años se ha propagado rápidamente a todas las regiones de la OMS. El virus del dengue se transmite a través de mosquitos hembra principalmente de la especie Aedes aegypti y, en menor grado, de la especie Ae. albopict...us. Estos mosquitos también son vectores de los virus de la fiebre chikungunya, la fiebre amarilla y el Zika. La enfermedad está muy extendida en los trópicos, con variaciones locales en el riesgo que dependen de los parámetros climáticos y de los factores sociales y ambientales.
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DNDi is now striving to make fexinidazole available to the majority of people who have T.b. gambiense sleeping sickness. We are supporting a three-year access and pharmacovigilance study that began in 2020 and have so far carried out in-country training of relevant staff in 250 hospitals and... health centres in T.b. gambiense-endemic countries; and updated national treatment and pharmacovigilance guidelines in Angola, Central African Republic, the Democratic Republic of Congo, Equatorial Guinea, Guinea, and Chad.
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