Weekly epidemiological record / Relevé épidémiologique hebdomadaire
22 SEPTEMBER 2017, 92th YEAR / 22 SEPTEMBRE 2017, 92e ANNÉE
No 38, 2017, 92, 557–572
There are 4 main forms of the disease: visceral leishmaniasis (VL, also known as kala-azar); post-kala-azar dermal leishmania...sis (PKDL); cutaneous leishmaniasis (CL); and mucocutaneous leishmaniasis (MCL). While cutaneous leishmaniasis is the most common form of the disease, visceral leishmaniasis is the most serious and can be fatal if untreated. Additionally, leishmaniasis can be classified as anthroponotic or zoonotic depending on whether the natural reservoir of the parasite is human or animal.
This report updates global epidemiological information on VL and CL to 2015, based on the main indicators published in the GHO, as of 1st September 2017.
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based on the WHO Bench Aids for the diagnosis of intestinal parasites;
Tutor’s Guide: perform specific laboratory techniques; identify intestinal parasites by genus and species; quantify helminth eggs in faeces by Kato-Katz procedure.
This Manual covers all important aspects of echinococcosis, including parasite biology and life-cycles, geographic distribution and prevalence, epidemiology, clinical presentation in humans and animals, diagnosis and treatment, as well as control and prevention using newly developed tools and method...s. It also provides descriptions of important techniques and a large number of bibliographical references.
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This report, published in conjunction with a summary overview of results of rounds 1–8, is the eighth and final report in a series of laboratory-based evaluations of rapid diagnostic tests (RDTs) for malaria. It provides a comparative measure of their performance in a standardized way to distingu...ish between well and poorly performing tests.
These results constitute the laboratory evaluation component of the WHO prequalification process for malaria RDTs and inform the current WHO procurement recommendations. In round 8, 35 RDTs from 17 manufacturers were assessed. For the first time the evaluation included an assessment of product performance against a panel of P. falciparum parasites with pfhrp2/3 gene deletions and therefore not expressing HRP2.
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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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23 March 2021
The meeting addressed the last key area, that is, determining the best method or combination of diagnostic methods for a control programme for S. stercoralis infections in humans.
Dr Montresor’s presentation highlighted that while there is currently no “gold standard” for the... diagnosis of S. stercoralis, there is a felt urgency to optimize diagnostic regimens that are currently available, and in the context of population-based testing (as opposed to individual focused diagnostics in clinical settings).
In other words, the diagnostic test(s) should have good accuracy, but we should remember that in public health we do not aim at individual diagnosis: rather, we need a tool that should help to estimate the prevalence in a population.
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The internationally recognized criteria for diagnosis of neurocysticercosis include a requirement for neuroimaging techniques, such as computerized tomography (CT) and/or magnetic resonance imaging (MRI), ideally supported by serology. These facilities are not available in all settings, especially i...n rural areas of low-income countries, making it difficult to identify and treat patients. Additionally, there is controversy about the role, type and duration of anthelmintic, antiinflammatory and antiepileptic drug (AED) treatments for different forms of neurocysticercosis.
These guidelines were developed to assist health-care providers in appropriate, evidence-based management of parenchymal neurocysticercosis. The guidelines do not address other forms of neurocysticercosis and do not include management of extraparenchymal disease (including cysticerci in the cerebral ventricles or subarachnoid space). The aim of the guidance is to improve decision-making to ensure appropriate patient care and to avoid misdiagnoses and inappropriate treatment of patients with neurocysticercosis.
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In the Region of the Americas, the leishmaniases are a group of diseases caused by various species of Leishmania, which cause a set of clinical syndromes in infected humans that can involve the skin, mucosa, and visceral organs. The spectrum of clinical disease is varied and depends on the interacti...on of several factors related to the parasite, the vector, and the host. Cutaneous leishmaniasis is the form most frequently reported in the Region and nearly 90% of cases present single or multiple localized lesions. Other cutaneous clinical forms, such as disseminated and diffuse cutaneous leishmaniasis, are more difficult to treat and relapses are common. The mucosal form is serious because it can cause disfigurement and severe disability if not diagnosed and treated early on. Visceral leishmaniasis is the most severe form, as it can cause death in up to 90% of untreated people.
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The Strategy to respond to antimalarial drug resistance in Africa is a technical and advocacy document, grounded in the best available evidence to date and aimed at minimizing the threat and impact of antimalarial drug resistance of Plasmodium falciparum parasites in Africa. Its objectives are to: i...) improve the detection of resistance to ensure a timely response; ii) delay the emergence of resistance to artemisinin and artemisinin-based combination therapy (ACT) partner drugs; and iii) limit the selection and spread of resistant parasites where resistance has been confirmed.
WHO Team
Global Malaria Programme
Editors
World Health Organization
Number of pages
87
Reference numbers
ISBN: 978 92 4 006026 5
Copyright
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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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In 2005, the World Health Organization (WHO) recognized Chagas disease (CD; Trypanosoma cruzi infection) as a neglected tropical disease (NTD) [1] and included it into the global plan to combat NTDs [2]. The Target 3.3 of the United Nations Sustainable Development Goals (UN/SDG) aims at ending the e...pidemics of NTDs by 2030 [3]. Mother-to-child (congenital/connatal) transmission is currently the main mode of transmission of T. cruzi over blood transfusions and organ transplantations in vector-free areas within and outside Latin America (LA). Based on recent demonstrations that congenital transmission can be prevented [4–7], WHO has shifted its objective, in 2018, from control to elimination of congenital CD (cCD).
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Trypanosoma cruzi is the etiological agent of Chagas disease (CD), considered one of the most important parasitic infections in Latin America. Between 25 and 90 million humans are at infection risk via at least one of multiple infection mechanisms. Under natural conditions, the principal transmissio...n modes are transplacental or via one of more than 140 hematophagous triatomine bugs (Reduviidae: Triatominae). Triatomines acquire the parasite from mammal reservoirs due to their obligate blood-feeding (albeit triatomines can also feed on non-reservoir vertebrates such as birds and reptiles). The disease burden for CD in the Latin America and Caribbean region, based on disability-adjusted life-years (DALYs), is at least five times greater than that of malaria, and is approximately one-fifth that of HIV/AIDS. In recent decades, CD has extended to other continents outside natural reservoir or vector distributions due to human migration, with a minimum estimated 10 million individuals infected worldwide.
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Chagas disease (CD) is caused by the parasite Trypanosoma cruzi, and it is endemic in Central, South America, Mexico and the
South of the United States. It is an important cause of early mortality and morbidity, and it is associated with poverty and stigma. A third of
the cases evolve into chronic... cardiomyopathy and gastrointestinal disease. The infection is transmitted vertically and by blood/organ
donation and can reactivate with immunosuppression. Case identification requires awareness and screening programmes targeting the
population at risk (women in reproductive age, donors, immunocompromised patients). Treatment with benznidazole or nifurtimox is most
effective in the acute phase and prevents progression to chronic phase when given to children. Treating women antenatally reduces but does
not eliminate vertical transmission. Treatment is poorly tolerated, contraindicated during pregnancy, and has little effect modifying the
disease in the chronic phase. Screening is easily performed with serology. Migration has brought the disease outside of the endemic
countries, where the transmission continues vertically and via blood and tissue/organ donations. There are more than 32 million migrants
from Latin America living in non-endemic countries. However, the infection is massively underdiagnosed in this setting due to the lack of
awareness by patients, health authorities and professionals. Blood and tissue donation screening policies have significantly reduced
transmission in endemic countries but are not universally established in the non-endemic setting. Antenatal screening is not commonly
done. Other challenges include difficulties accessing and retaining patients in the healthcare system and lack of specific funding for the
interventions. Any strategy must be accompanied by education and awareness campaigns directed to patients, professionals and policy
makers. The involvement of patients and their communities is central and key for success and must be sought early and actively. This review
proposes strategies to address challenges faced by non-endemic countries
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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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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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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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The "Primary Healthcare Standard Treatment Guidelines and Essential Medicines List" by the South African National Department of Health provides evidence-based guidelines for diagnosing and managing common medical conditions at the primary healthcare level. This document includes treatment protocols ...for various health issues, such as infections, chronic diseases, maternal and child health, mental health, and emergency care. It aims to standardize care, promote rational medicine use, and ensure equitable access to essential medications across South Africa. The guidelines emphasize prevention, accurate diagnosis, and efficient treatment strategies to improve patient outcomes.
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Severe and difficult asthma in a low- and middle-income country (LMIC) can relate to lack of availability of basic medications; potentially reversible factors such as poor adherence or comorbidities such as obesity inhibiting a good response to treatment; and (rarely) true severe, therapy-resistant ...asthma. However, definitions of severity should encompass not merely doses of prescribed medication, but also underlying risk. The nature of asthmatic airway disease shows geographical variation, and LMIC asthma should not be assumed to be phenotypically the same as that in high-income countries (HICs). The first assessment step is to ensure another diagnosis is not being missed. Largely, political action is needed if children with asthma are to get access to basic medications. If a child is apparently not responding to low dose, simple medications, the next step is not to increase the dose but perform a detailed assessment of what factors (for example co-morbidities such as obesity, or social factors like poor adherence) are inhibiting a treatment response; in most cases, an underlying reason can be found. An assessment of risk of future severe asthma attacks, side-effects of medication and impaired lung development is also important. True severe, therapy-resistant asthma is rare and there are multiple underlying molecular pathologies. In HICs, steroid-resistant eosinophilia would be treated with omalizumab or mepolizumab, but the cost of these is prohibitive in LMICs, the biomarkers of successful therapy are likely only relevant to HICs. In LMICs, a raised blood eosinophil count may be due to parasites, so treating asthma based on the blood eosinophil count may not be appropriate in these settings.
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