PLoS ONE 13(8): e0202499. https://doi.org/10.1371/journal.pone.0202499
This was a school-based cross-sectional study conducted in 2015 among 305 school children aged 7–16 years from two primary schools located in Ilemela and Magu Districts, north-western Tanzania. Single stool and urine samples w...ere collected from each participant and examined for the presence of Schistosoma mansoni eggs, parasite antigen, and parasite DNA using KK thick smears, POC-CCA tests, and real-time PCR, respectively.
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The Lancet October 25, 2022DOI:https://doi.org/10.1016/S0140-6736(22)01540-9
As climate change’s impacts continue to accrue, countries are persistently making wrong choices that are harming human health.
A desperate global thirst for fossil fuels is worsening climate change, leading to more extr...eme weather events that have hit every continent, led to thousands of deaths, and caused $250+ billion in damage in 2021.
• People 65+ and children <1 experienced 3.7 billion more heatwave days in 2021 than the annual average from 1986–2005.
• Heat-related deaths shot up 68% from 2000–2004 to 2017–2021.
• Climate change is abetting infectious disease transmission, warming coastal waters and leading to the spread of Vibrio bacteria like the one that causes cholera, and expanding the reach of the malaria parasite.
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The Global Programme to Eliminate Lymphatic Filariasis (LF) is using mass drug administration (MDA) of antifilarial medications to treat filarial infections, prevent disease and interrupt transmission. Almost 500 million people receive these medications each year. Clinical trials have recently shown... that a single dose of a triple-drug combination comprised of ivermectin, diethylcarbamazine and albendazole (IDA) is dramatically superior to widely used two-drug combinations for clearing larval filarial parasites from the blood of infected persons. A large mul-
ticenter community study showed that IDA was well-tolerated when it was provided as MDA. IDA was rapidly advanced from clinical trial to policy and implementation; it has the potential to accelerate LF elimination in many endemic countries.
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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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Pathogens . 2021 Nov 16;10(11):1493.doi: 10.3390/pathogens10111493
.Chronic manifestations of Chagas disease present as disabling and life-threatening condi-tions affecting mainly the cardiovascular and gastrointestinal systems. Although meaningful research has outlined the different molecular mech...anisms underlying Trypanosoma cruzi’s infection and the host-parasite interactions that follow, prompt diagnosis and treatment remain a challenge, particu-larly in developing countries and also in those where the disease is considered non-endemic. This review intends to present an up-to-date review of the parasite’s life cycle, genetic diversity, virulence factors, and infective mechanisms, as well as the epidemiology, clinical presentation, diagnosis, and treatment options of the main chronic complications of Chagas disease.
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Over 6 million people worldwide are infected with Trypanosoma cruzi, the protozoan that causes Chagas disease. Endemic in 21 Latin American countries, the disease can be transmitted by vector insects called triatomines — also known as “kissing bugs” —, foods or beverages contaminated with th...e parasite, blood transfusions, organ transplants, or congenitally during pregnancy or delivery.
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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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More countries eliminate human African trypanosomiasis as a public health problem: Benin and Uganda (gambiense form) and Rwanda (rhodesiense form)
Human African trypanosomiasis (HAT), or sleeping sickness, transmitted by tsetse flies in sub-Saharan Africa, is a life-threatening disease that afflict...s poor rural populations. It is caused by trypanosome parasites of 2 subspecies: Trypanosoma brucei gambiense in West and Central Africa, and T. b. rhodesiense in East Africa.
HAT transmission can be reduced and interrupted by deploying and maintaining capacities for testing people at risk in order to detect and treat cases, and by controlling tsetse populations that are in contact with humans.
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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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Today is World Chagas Disease Day. This year’s theme is Finding and reporting every case to defeat Chagas disease.
Despite progress, the global case detection rate for Chagas disease is low (estimated to be around 10%), posing a substantial barrier to accessing treatment and care and in prevent...ing transmission.
Often termed as a “silent and silenced disease”, many people with Trypanosoma cruzi infection (the parasite that causes the disease) develop no symptoms or unspecific mild symptoms. Moreover, many countries with cases lack systems to track the number of affected people and active transmission routes.
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La Stratégie de riposte face à la résistance aux antipaludiques en Afrique est un document technique de sensibilisation qui se fonde sur les bases factuelles les plus solides dont on dispose et vise à réduire au maximum la menace et l’impact de la résistance aux antipaludiques de Plasmodium ...falciparum en Afrique. Elle a pour objectifs i) d’améliorer la détection de la résistance et d’assurer une riposte en temps utile ; ii) de retarder l’émergence de la résistance à l’artémisinine et aux médicaments associés utilisés dans les combinaisons thérapeutiques à base d’artémisinine (CTA) ; et iii) de freiner la sélection et la propagation des parasites résistants là où une pharmacorésistance est confirmée. Si la Stratégie cible l’Afrique, il convient de noter que la
menace de la résistance aux antipaludiques concerne tous les pays d’endémie palustre et que les interventions proposées dans le présent document sont applicables dans d’autres régions géographiques à condition d’être adaptées aux spécificités locales.
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Leishmaniasis is a major vector-borne disease caused by obligate intramacrophage protozoa of the genus Leishmania, and transmitted by the bite of phlebotomine female sand flies of the genera Phlebotomus and Lutzomyia, in the old and new worlds, respectively. Among 20 well-recognized Leishmania speci...es known to infect humans, 18 have zoonotic nature, which include agents of visceral, cutaneous, and mucocutaneous forms of the disease, in both the old and new worlds. Currently, leishmaniasis show a wider geographic distribution and increased global incidence. Environmental, demographic and human behaviors contribute to the changing landscape for zoonotic cutaneous and visceral leishmaniasis. The primary reservoir hosts of Leishmania are sylvatic mammals such as forest rodents, hyraxes and wild canids, and dogs are the most important species among domesticated animals in the epidemiology of this disease. These parasites have two basic life cycle stages: one extracellular stage within the invertebrate host (phlebotomine sand fly), and one intracellular stage within a vertebrate host. Co-infection with HIV intensifies the burden of visceral and cutaneous leishmaniasis by causing severe forms and more difficult to manage. The disease is endemic to Ethiopia, and the clinical signs are not pathognomic. The visceral form (Kala-azar) may be confused with other similar conditions such as malaria, tropical splenomegaly, schistosomiasis, milliary tuberculosis, and brucellosis. Similarly, cutaneous leishmaniasis should be differentiated from disease like tropical ulcers, impetigo and leprosy. There are several methods of laboratory diagnosis of leishmaniasis, including parasitological, immunological and molecular. Different forms of treatments are available including oral, parenteral, and topical medications such as pentavalent antimonials, liposomal amphotericin B, miltefosine and paromomycin. Methods of control are largely limited to destruction of animal reservoirs, treatment of infected humans, and management of sand fly populations. Development of an effective vaccine against leishmaniasis has been largely unsuccessful and hinders its prevention.
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In 2012, the World Health Organisation (WHO) set out a roadmap for the control, elimination, or eradication of 17 neglected tropical diseases by 2020. Many were skeptical about the achievability of such goals. Now, still two years away from that end point, good news is emerging for gambiense human A...frican trypanosomiasis (HAT), or sleeping sickness, caused by the tsetse-fly−transmitted protozoan parasite Trypanosoma brucei gambiense in West and Central Africa. The Rhodesiense form of the disease is being pursued under a separate programme.
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Leishmaniases are a group of diseases of zoonotic importance caused by over 20 species of protozoa of the genus Leishmania, in which domestic dogs are considered to be the main reservoir for the disease. However, the involvement of other vertebrates as reservoirs for these parasites has also been in...vestigated. Therefore, the objective of the present study was to carry out a systematic review with meta-analysis on occurrences of leishmaniasis in equids. The case reports described animals with cutaneous symptoms of leishmaniasis (papules, nodules, ulcers or crusts) that regressed spontaneously, located mainly on the head and limbs, from which three species of protozoa were identified in the lesions: Leishmania braziliensis, Leishmania infantum and Leishmania siamensis. In turn, the meta-analysis showed a combined prevalence of 25%, although with high heterogeneity among the studies, which was attributed to the use of different methods for diagnosing the disease. Leishmaniasis in equids is a benign disease but it should be included in the differential diagnosis of cutaneous diseases among these species. Seroepidemiological studies are important in investigating and monitoring suspected exposure of these hosts to the parasite, especially in endemic areas. However, there is also a need to standardize diagnostic methods.
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A century after its discovery, Chagas' disease still represents a major public health challenge in Latin America. Moreover, because of growing population movements, an increasing number of cases of imported Chagas' disease have now been detected in non-endemic areas, such as North America and some E...uropean countries. This parasitic zoonosis, caused by Trypanosoma cruzi, is transmitted to humans by infected Triatominae insects, or occasionally by non-vectorial mechanisms, such as blood transfusion, mother to fetus, or oral ingestion of materials contaminated with parasites. Following the acute phase of the infection, untreated individuals enter a chronic phase that is initially asymptomatic or clinically unapparent. Usually, a few decades later, 40-50% of patients develop progressive cardiomyopathy and/or motility disturbances of the oesophagus and colon. In the last decades several interventions targeting primary, secondary and tertiary prevention of Chagas' disease have been attempted. While control of both vectorial and blood transfusion transmission of T cruzi (primary prevention) has been successful in many regions of Latin America, early detection and aetiological treatment of asymptomatic subjects with Chagas' disease (secondary prevention) have been largely underutilised. At the same time, in patients with established chronic disease, several pharmacological and non-pharmacological interventions are currently available and have been increasingly used with the intention of preventing or delaying complications of the disease (tertiary prevention). In this review we discuss in detail each of these issues.
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The previous report of the WHO Expert Committee on this disease
followed a meeting in 1995. Intensive, coordinated efforts against HAT during
the intervening 18 years have resulted in a decrease in incidence to a point at
which elimination is considered feasible. This report provides informati...on about
new diagnostic approaches, new therapeutic regimens and better understanding
of the distribution of the disease with high-quality mapping. The roles of human
and animal reservoirs and the tsetse fly vectors that transmit the parasites are
emphasized. The new information has formed the basis for an integrated strategy
with which it is hoped that elimination of HAT will be achieved. The report also
contains recommendations on the approaches that will lead to elimination of the
disease.
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Soil-transmitted helminth (STH) infections are among the most common infections worldwide with an estimated 1.5 billion infected people or 24% of the world’s population. These infections affect the poorest and most deprived communities with poor access to clean water, sanitation and hygiene in tro...pical and subtropical areas, with the highest prevalence reported from sub-Saharan Africa, China, South America and Asia. They are transmitted by eggs present in human faeces, which in turn contaminate soil in areas where sanitation is poor. Over 260 million preschool-age children, 654 million school-age children,108 million adolescent girls and 138.8 million pregnant and lactating women live in areas where these parasites are intensively transmitted, and are in need of treatment and preventive interventions.
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Les géohelminthiases comptent parmi les infections les plus courantes dans le monde, plus de 1,5 milliard de personnes, soit près de 24 % de la population mondiale, étant infestées à l’échelle mondiale. Ces infections touchent les communautés les plus pauvres et les plus défavorisées ayan...t un accès limité à l’eau potable, à l’assainissement et à l’hygiène dans les régions tropicales et subtropicales, la plus forte prévalence étant recensée en Afrique subsaharienne, en Chine, en Amérique du Sud et en Asie. Elles se transmettent par des œufs présents dans les excréments humains, qui contaminent les sols là où les conditions d’assainissement sont insuffisantes. Plus de 260 millions d’enfants d’âge préscolaire, 654 millions d’enfants d’âge scolaire, 108 millions d’adolescentes et 138,8 millions de femmes enceintes ou allaitantes vivent dans des zones où il existe une transmission à grande échelle de ces parasites et nécessitent un traitement et la mise en place de mesures préventives.
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Following the publication of Guidelines on certification of elimination of human onchocerciasis in 2001 by the World Health Organization (WHO), these are the first evidence-based guidelines developed by NTD Department according to the international standards. They provide a set of recommendations th...at would guide national programme managers in collaboration with their respective oversight committees on when to stop mass drug administration (MDA) and conduct post-treatment surveillance (PTS) activities for a minimum period of 3 to 5 year before confirming the interruption of transmission of Onchocerca volvulus parasite and hence its elimination. They also include steps to undertake for verification of elimination of transmission of the parasite in the whole endemic country by the International Verification Team (IVT) prior to the official acknowledgement by WHO Director General.
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Human schistosomiasis is caused mainly by 3 schistosome species: Schistosoma haematobium, S. mansoni and S. japonicum. S. guineensis, S. intercalatum and S. mekongi have a highly localized distribution in Central Africa and along the Mekong River in South-East Asia, respectively. Soil-transmitted h...elminthiases (STH) are infections caused by 4 parasite species: Ascaris lumbricoides, Trichuris trichiura, Ancylostoma duodenale and Necator americanus. The 2 latter species are indistinguishable microscopically and are usually reported together as “hookworms”. Schistosomiasis and STH are neglected tropical diseases (NTDs) and are transmitted mainly in areas with poor access to clean water and sanitation. The presence of an intermediate snail host in water is essential to allow Schistosoma to complete their life cycle. Schistosomiasis and STH can cause significant morbidity, including anaemia, nutritional disturbances and, in the case of schistosomiasis, granuloma, organ pathology and cancer, and an increased risk of acquisition of HIV. In women, urogenital schistosomiasis may cause vaginal bleeding, pain during sexual intercourse and nodules in the vulva, now described as female genital schistosomiasis. Groups at risk for STH and schistosomiasis are those in need of micronutrients: preschool-aged children (pre-SAC, 1–4 years of age), school-aged children (SAC, 5–14 years), women of reproductive age (WRA) and, in addition for schistosomiasis adult and entire communities in high-risk areas.
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