La fourniture de sang et de produits sanguins sûrs et efficaces pour la transfusion ou la fabrication d’autres produits sanguins fait intervenir un certain nombre de processus, allant de la sélection des donneurs de sang et de la collecte, au traitement et au dépistage des dons de sang ainsi qu...’à l’analyse des échantillons des malades, à la délivrance de sang compatible et à son administration au patient. Il existe un risque d’erreur à chaque étape de la « chaîne de transfusion », et une défaillance à une quelconque de ces étapes peut avoir des conséquences graves pour les receveurs du sang ou des produits sanguins. Si la transfusion sanguine peut sauver des vies, elle comporte aussi des risques, en particulier la transmission des infections par le sang.
Le dépistage des infections transmissibles par transfusion (ITT) en vue d’exclure les dons de sang présentant un risque de transmettre une infection du donneur aux receveurs est une étape critique du processus visant à garantir au mieux la sécurité des transfusions. Un dépistage efficace des agents transmissibles par le sang les plus courants et les plus dangereux peut réduire le risque de transmission à des niveaux très faibles.
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L’évaluation externe de la qualité (EEQ) est une composante importante des systèmes qualité des services de transfusion sanguine. L’EEQ est l’évaluation externe de la qualité générale des résultats obtenus par un laboratoire dans l’analyse d’échantillons de contrôle dont le cont...enu est connu, mais n’a pas été dévoilé, et la comparaison de ces résultats avec ceux qu’ont obtenus d’autres laboratoires qui ont analysé les mêmes échantillons. Dans les laboratoires qui pratiquent le dépistage des infections transmissibles par transfusion (ITT) dans les dons de sang, la participation à l’EEQ aide à surveiller et améliorer la qualité des résultats. Les informations issues de l’EEQ permettent d’améliorer continuellement la qualité en mettant en évidence les erreurs d’un laboratoire et d’appliquer des mesures pour éviter qu’elles se reproduisent. L’EEQ joue ainsi un rôle essentiel dans l’amélioration de la sécurité transfusionnelle.
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The paper provides the rationale for these recommendations, which are based on analyses of data from the TRACT trial.
Mais pessoas morrem a cada ano de doenças cardiovasculares do que de qualquer outra causa. Mais de três quartos das mortes por doenças cardíacas e acidentes vasculares cerebrais ocorrem em países de baixa e média renda. A hipertensão - ou pressão alta - é uma condição médica grave que au...menta significativamente o risco de doenças cardíacas, cerebrais, renais e outras doenças. A hipertensão pode ser definida usando níveis específicos de pressão sistólica e diastólica ou o uso reportado de medicamentos anti-hipertensivos.
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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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Leishmaniasis is a parasitic disease caused by intracellular protozoan parasites of the genus Leishmania (Trypanosomatidae family); it is endemic in more than 98 countries worldwide [1]. Visceral (VL) and cutaneous (CL) leishmaniasis are the most common forms of the disease. VL causes a systemic dis...ease characterised by fever, hepatosplenomegaly, anaemia and lymph node enlargement and may be fatal without appropriate treatment, while CL mainly causes skin ulcers and is considered a less severe form of the disease [2]. The incubation period for VL varies from 10 days up to nearly 3 years and for CL from 2 weeks to 3 years [3]. The natural route of transmission is a bite of blood-feeding phlebotomine sandflies; it may be zoonotic or anthroponotic, depending on the parasite species and the geographical location
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Noncommunicable diseases (NCDs) are responsible for 81% of all deaths in the region of the Americas, of which 34% befall prematurely in people between 30- 69 years old. The burden of theses diseases and their common risk factors jeopardize the health systems to provide adequate management, as well a...s to implement customized policies and interventions. The PAHO/WHO STEPwise approach to NCD risk factor surveillance (STEPS) is a simple, sequential, standardized method for collecting, analyzing, and disseminating data on key NCD risk factors in countries in adults from 18 to 69 years old. This survey covers key modifiable risk factors: tobacco use, alcohol use, physical inactivity, and unhealthy diet, as well as key biological risk factors: overweight and obesity, raised blood pressure, raised blood glucose, and abnormal blood lipids. STEPS is a household survey that gathers information on the risk factors through a face-to-face interview (step 1), simple physical measurements (step 2), and collection of urine and blood samples for biochemical analysis (step 3). Every step has a core set of questions, measurements, and expanded sets depending on the countries' needs and interests. It also has optional modules. Implementing STEPS allows the comparability of data within and between countries due to its standardized data collection. It also helps health services plan public health priorities and monitors and evaluates population-wide interventions. It is designed to help countries build and strengthen their capacity to conduct surveillance. STEPS captures 11 of the 25 indicators outlined in the NCD Global Monitoring Framework relating to 7 of the nine global targets.
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Taenia saginata is a zoonotic tapeworm that is of economic importance in countries where cattle are kept. The parasite is transmitted from human tapeworm carriers (taeniosis) to bovines (cysticercosis) by excretion of eggs or proglottids containing eggs into the environment via the stool. Bovines ca...n then ingest the eggs through contaminated feed or water. After ingestion, the eggs hatch and release oncospheres in the small intestines, where the oncospheres penetrate the intestinal wall to reach the blood circulation. This distributes them throughout the body, but primarily to muscle tissue, where they develop into cysticerci. For humans to become infected with T. saginata, raw or undercooked bovine meat or offal containing infective cysts must be consumed. Bovine cysticercosis has been associated with various environmental factors related to water sources, such as animals having access to surface water, flooding of pastures and proximity to wastewater sources.
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Diabetes mellitus (DM) is a global epidemic with significant morbidity. Diabetic
retinopathy (DR) is the specific microvascular complication of DM and affects 1 in 3 persons with DM. DR remains a leading cause of vision loss in working adult populations. Patients with severe levels of DR are report...ed to have poorer quality of life and reduced levels of physical, emotional, and social well-being, and they utilize more health care resources.
Epidemiological studies and clinical trials have shown that optimal control of blood glucose, blood pressure, and blood lipids can reduce the risk of developing retinopathy and slow its progression. Timely treatment with laser photocoagulation, and increasingly, the appropriate use of intraocular administration of vascular endothelial growth factor (VEGF) inhibitors can prevent visual loss in vision- threatening retinopathy, particularly diabetic macular edema (DME). Since visual loss may not be present in the earlier stages of retinopathy, regular screening of persons with diabetes is essential to enable early intervention.
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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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oil-transmitted helminth (STH) infections are among the most common infections worldwide and affect the poorest and most deprived communities.
They are transmitted by eggs present in human faeces which in turn contaminate soil in areas where sanitation is poor.
The main species that infect peopl...e are the roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and the hookworms (Necator americanus and Ancylostoma duodenale).
Intestinal worms produce a wide range of symptoms including intestinal manifestations (diarrhoea, abdominal pain), general malaise and weakness. Hookworms cause chronic intestinal blood loss that result in anaemia.
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WHO today released its first roadmap to tackle postpartum haemorrhage (PPH) – defined as excessive bleeding after childbirth - which affects millions of women annually and is the world’s leading cause of maternal deaths.
Despite being preventable and treatable, PPH results in around 70 000 de...aths every year. For those who survive, it can cause disabilities and psychological trauma that last for years.
“Severe bleeding in childbirth is one of the most common causes of maternal mortality, yet it is highly preventable and treatable,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General. “This new roadmap charts a path forward to a world in which more women have a safe birth and a healthy future with their families.”
The Roadmap aims to help countries address stark differences in survival outcomes from PPH, which reflect major inequities in access to essential health services. Over 85% of deaths from PPH happen in sub-Saharan Africa and South Asia. Risk factors include anaemia, placental abnormalities, and other complications in pregnancy such as infections and pre-eclampsia.
Many risk factors can be managed if there is quality antenatal care, including access to ultrasound, alongside effective monitoring in the hours after birth. If bleeding starts, it also needs to be detected and treated extremely quickly. Too often, however, health facilities lack necessary healthcare workers or resources, including lifesaving commodities such as oxytocin, tranexamic acid or blood for transfusions.
“Addressing postpartum haemorrhage needs a multipronged approach focusing on both prevention and response - preventing risk factors and providing immediate access to treatments when needed - alongside broader efforts to strengthen women’s rights,” said Dr Pascale Allotey, WHO Director for Sexual and Reproductive Health and HRP, the UN’s special programme on research development and training in human reproduction. “Every woman, no matter where she lives, should have access to timely, high quality maternity care, with trained health workers, essential equipment and shelves stocked with appropriate and effective commodities – this is crucial for treating postpartum bleeding and reducing maternal deaths.”
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