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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Last accessed on 05.03.2023
Snakebite envenoming is a potentially life-threatening disease that typically results from the injection of a mixture of different toxins (“venom”) following the bite of a venomous snake. Envenoming can also be caused by venom being sprayed into a person’s eyes by certain species of snakes tha...t have the ability to spit venom as a defence measure. Not all snakebites result in envenoming: some snakes are non-venomous and venomous snakes do not always inject venom during a bite. About 50–55% of all snakebites result in envenoming. Snake venoms are complex mixtures of protein and peptide toxins, varying from one species to another, and even within species. The toxins in snake venoms are evolutionarily adapted to interact with a large variety of cellular targets in the organisms exposed to them. In humans and animals, snakebite envenoming affects multiple organ systems (depending on the particular species of snake and the classes of toxins present in the venom) and can cause, among other things: haemorrhage and prolonged disruption of haemostasis, neuromuscular paralysis, tissue necrosis, myolysis (muscle degeneration), cardiotoxicity, acute kidney injury, thrombosis and hypovolaemic shock.
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Snakebite envenoming affects millions of people worldwide annually and is a significant source of mortality. Preventing and treating the problem is complex and requires collaboration among the fields of public health, medicine, ecology, and laboratory science. After being removed from the category A... neglected tropical disease (NTD) list in 2013, snakebite envenoming was reinstated in 2017 in response to antivenom shortages and advocacy from researchers and international NGOs. In 2019, the World Health Organization (WHO) set a target to halve the number of deaths and cases of snakebite envenoming by 2030.
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Snakebite envenoming is a serious public health problem in Central America, where approximately 5,500 cases occur every year. Panama has the highest incidence and El Salvador the lowest. The majority, and most severe, cases are inflicted by the pit viper Bothrops asper (family Viperidae), locally kn...own as ‘terciopelo’, ‘barba amarilla’ or ‘equis’. About 1% of the bites are caused by coral snakes of the genus Micrurus (family Elapidae). Despite significant and successful efforts in Central America regarding snakebite envenomings in the areas of research, antivenom manufacture and quality control, training of health professionals in the diagnosis and clinical management of bites, and prevention of snakebites, much remains to be done in order to further reduce the impact of this medical condition. This essay presents seven challenges for improving the confrontation of snakebite envenoming in Central America. Overcoming these challenges demands a coordinated partnership of highly diverse stakeholders though inter-sectorial and inter-programmatic interventions.
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Humans can become infected with T. saginata or T. asiatica when they consume infected beef meat or pig liver tissue, respectively, which has not been adequately cooked, but taeniasis due to T. saginata or T. asiatica has no major impact on human health. Therefore, this fact sheet refers to the trans...mission and health impacts of T. solium only.
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Taeniasis and cysticercosis caused by the parasite T. solium affect vulnerable populations,
mainly in Latin America, sub-Saharan Africa and Asia, where pigs (the intermediate host) roam
free and poor sanitation allows pigs access to human faeces.
The major neglected tropical diseases, Taenia solium taeniosis/cysticercosis and schistosomiasis caused by Schistosoma mansoni or S. haematobium are presumed to be widely distributed in Africa. Taenia solium taeniosis/ cysticercosis has been reported as an emerging disease in different regions of Af...rica [1, 2], but currently the exact distribution remains unclear. Reported prevalences of T. solium taeniosis and cysticercosis in African countries are not extensive and are further complicated by the lack of ‘gold standard’ tests for diagnosis.
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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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Yaws, a neglected tropical disease (NTD) of the skin caused by the bacterium Treponema pallidum subspecies pertenue, is targeted in the latest WHO NTD Roadmap for eradication by 2030. In January, 2022, WHO published a manual that outlines the key activities that Ministries of Health in endemic count...ries should undertake to achieve this goal. The aim of the manual is to provide guidance on surveillance and evaluation of yaws as programmes progress towards eradication. However, yaws eradication in Africa faces several challenges.
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Yaws is targeted for eradication by 2030, using a strategy based on mass drug administration (MDA) with azithromycin. New diagnostics are needed to aid eradication. Serology is currently the mainstay for yaws diagnosis; however, inaccuracies associated with current serological tests makes it difficu...lt to fully assess the need for and impact of eradication campaigns using these tools. Under the recommendation of the WHO Diagnostic Technical Advisory Group (DTAG) for Neglected Tropical Diseases(NTDs), a working group was assembled and tasked with agreeing on priority use cases for developing target product profiles (TPPs) for new diagnostics tools.
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In 2018, we are celebrating 20 years of progress in eliminating trachoma, the world’s leading infectious cause of blindness. Set up in 1998 by Pfizer Inc. and the Edna McConnell Clark Foundation, the International Trachoma Initiative (ITI) supports Ministries of Health in over 30 countries around ...the world by making Zithromax® available for use in public health campaigns to eliminate trachoma. The 20th anniversary of our founding gives us an opportunity to reflect on the distance we’ve traveled in fighting this disease, and raise the ambition for accelerating to a world where diseases like trachoma are a distant memory. We have not traveled alone these past 20 years – a broad coalition of actors including NGOs, the World Health Organization (WHO), Ministries of Health, health workers, and community members have made these incredible achievements possible. Our 20th anniversary gives us an opportunity to celebrate this coalition of partners, colleagues, and friends
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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 schistosomiasis
prevention and control. To this must b...e 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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Rabies is fatal, vaccine-preventable disease responsible for an estimated 59,000 human deaths each year. Most cases are transmitted by dogs, and most deaths occur in underserved populations in Africa and Asia. Approximately 40% of deaths occur in children.
Rabies is entirely preventable, and vaccines, medicines, tools and technologies have long been available to prevent people from dying of dog-mediated rabies. Nevertheless, rabies still kills about 60 000 people a year, of whom over 40% are children under 15, mainly in rural areas of economically dis...advantaged countries in Africa and Asia. Of all human cases, up to 99% are acquired from the bite of an infected dog.
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Accessed on 07.03.2023
A – Z of Rabies – A guide to the world´s deadliest disease
Mission Rabies
In their 2015 declaration "Transforming our world: the 2030 Agenda for Sustainable Development", Member States pledged to end the epidemics of AIDS, tuberculosis, malaria and neglected tropical diseases by 2030, and to combat hepatitis and other communicable diseases. This report reviews progress an...d challenges in the global response to reduce the burden of these diseases in the context of the Millennium Development Goals, and looks ahead to identify the strategies and approaches that will be needed to accelerate progress during the new development era. The report was developed by WHO's Cluster for HIV/AIDS, TB, Malaria and Neglected Tropical Diseases in 2015.
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The new WHO recommendations for rabies immunization supersede the 2010 WHO position
on pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) for rabies. These updated
recommendations are based on new evidence and directed by public health needs that are cost-,
dose- and time-sparing..., while assuring safety and clinical effectiveness. In addition, new guidance on
prudent use of rabies immunoglobulins (RIG) is provided.
The following sections summarize the main points of the updated WHO position as endorsed by the
Strategic Advisory Group of Experts on immunization (SAGE) at its meeting in October 20171. The full
version of the WHO position on rabies vaccines and immunoglobulins will be published in the Weekly
Epidemiological Record2 in April 2018.
Rabies prevention involves two main strategies: (i) dog vaccination to interrupt virus transmission to
humans; and (ii) human vaccination as a series of vaccine administrations before or after an exposure.
Currently, rabies vaccines made from inactivated cell cultures are extremely well tolerated and have no
contraindications.
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Rabies is a neglected zoonotic disease with a global burden of approximately 59,000 human deaths a year. Once clinical symptoms appear, rabies is almost invariably fatal; however, with timely and appropriate post-exposure prophylaxis (PEP) consisting of wound washing, vaccine, and in some cases rabi...es immunoglobulin (RIG), the disease is almost entirely preventable. Access to PEP is limited in many countries, and when available, is often very expensive.
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Rabies is a public health problem in Asia and vaccine affordability is an issue.
There is no reduction in the number of persons seeking post-exposure prophylaxis.
The high cost of cell culture vaccines for intramuscular use is a limiting factor.
Intradermal rabies vaccination offers cost-effectiv...e alternative to intramuscular.
WHO recommended one week intradermal schedule will ensure good patient compliance.
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