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.
more
Tuberculosis (TB) is an infectious disease that usually affects the lungs, though it can affect any organ in the body. It can develop when bacteria spread through droplets in the air. TB can be fatal, but in many cases, TB is preventable and treatable. This report examines the human rights impact of... the prevalence of Tuberculosis (TB) and Multi-drug-resistant tuberculosis (MDR-TB) among the Indigenous San peoples of Namibia. Combining political economy and root-cause methodology, the report explores the socioeconomic factors that make the San vulnerable to TB and limit their access to adequate health services.
more
Curr Opin Pharmacol . 2022 Apr;63:102203.doi: 10.1016/j.coph.2022.102203. Epub 2022 Feb 11.
The COVID-19 pandemic has widespread economic and social effects on Latin America (LA) and the Caribbean (CA). This region, which has a high prevalence of chronic diseases, has been one of the most affected... during the pandemic. Multiple symptoms and comorbidities are related to distinct COVID-19 outcomes. However, there has been no explanation as to why different patients present with different arrays of clinical presentations. Studies report that similar to comorbidities, each country in LA and the CA has its own particular health issues.
more
The updated guidelines present a standard minimum dataset, priority indicators and recommendations to strengthen data use across HIV prevention, testing and treatment, and linkages to services for sexually transmitted infections, viral hepatitis, tuberculosis and cervical cancer. The guidelines also... cover the use of routinely collected data for HIV surveillance (including measurement of HIV prevalence and incidence) and emphasize the use of data from different sources to gain a better picture of epidemiologic trends. The whole collection you can download from here https://www.who.int/publications/i/item/9789240055315
more
The updated guidelines present a standard minimum dataset, priority indicators and recommendations to strengthen data use across HIV prevention, testing and treatment, and linkages to services for sexually transmitted infections, viral hepatitis, tuberculosis and cervical cancer. The guidelines also... cover the use of routinely collected data for HIV surveillance (including measurement of HIV prevalence and incidence) and emphasize the use of data from different sources to gain a better picture of epidemiologic trends.
more
Many determinants are known to affect brain health at different stages of life. The position paper provides a conceptual framework for what brain health is and how brain health can be optimized throughout life with actions across the following clusters of determinants: physical health, healthy envir...onments, safety and security, learning and social connection, and access to quality services. Optimizing brain health can not only reduces the prevalence and burden of neurological disorders, but also improve mental and physical health overall and create positive social and economic impacts, all of which contribute to greater well-being and help advance society, irrespective of the presence or absence of disorders.
more
Lymphatic filariasis is a neglected tropical disease that can cause permanent disability through disruption of the lymphatic system. This disease is caused by parasitic filarial worms that are transmitted by mosquitos. Mass drug administration (MDA) of antihelmintics is recommended by WHO to elimina...te lymphatic filariasis as a public health problem. This study aims to produce the first geospatial estimates of the global prevalence of lymphatic filariasis infection over time, to quantify progress towards elimination, and to identify geographical variation in distribution of infection.
more
Human schistosomiasis otherwise called bilharzia, is a fresh- water snail transmitted intravascular debilitating disease resulting from infection by the parasitic dimorphic Schistosoma trematode worms, which lives in the bloodstream of humans. The World Health Organization (WHO) regards the disease ...as a neglected tropical disease, with an estimated 732 million persons being vulnerable to infection worldwide in renowned transmission areas. Steinmann and co-workers documented that over 200 million individuals from Africa, Asia, and South America are infected with this disease. The WHO further estimated that schistosome infections and geohelminths accounts for over 40% of the world tropical disease burden with the exclusion of malaria. Humans get infected with this disease when they make contact with water contaminated with the skin-penetrating cercariae. Prevalence of schistosomiasis, at present, is still high in sub-Saharan Africa. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those from sub-Saharan Africa only. Approximately 120 million individuals in sub-Saharan Africa have schistosomiasis-related symptoms while about 20 million undergo hardship as a result of chronic presentations of the disease.
more
Goal and objectives of the guideline
The goal of this guideline is to provide evidence-based recommendations to countries in their efforts to accomplish schistosomiasis morbidity control and elimination as a public health problem, and to move towards interruption of transmission.
The recommendatio...ns contained herein will help countries to implement national schistosomiasis control and elimination programmes and support efforts to verify the interruption of transmission.
The specific objectives are to provide guidance on:
prevalence thresholds, target age groups and frequency of preventive chemotherapy for schistosomiasis;
establishment of water, sanitation and hygiene (WASH) and snail control activities to support control and elimination of schistosomiasis;
use of diagnostic tests in humans in low transmission areas and for moving to, and evaluating the interruption of transmission of schistosomiasis;
tools for the assessment of Schistosoma spp. infection in snail hosts; and
diagnostic tests for the assessment of schistosomiasis infection in animal reservoirs of infection
more
Les pays progressent vers la réalisation de l’objectif mondial tendant à ce que, d’ici 2025, 95 pour cent des personnes qui vivent avec le VIH connaissent leur statut sérologique. Cependant, en 2020, on estimait encore à 6 millions le nombre de personnes séropositives non diagnostiquées da...ns le monde. Les hommes vivant dans des lieux où la prévalence du VIH est élevée et les hommes appartenant aux populations clés, tous lieux confondus, ont moins de chances de connaître leur séropositivité que les femmes. Ainsi, au niveau mondial, 78 pour cent des hommes de plus de 15 ans connaissent leur statut sérologique, contre 86 pour cent chez les femmes de cette même tranche d’âge.
more
Les pays progressent vers la réalisation de l’objectif mondial tendant à ce que, d’ici 2025, 95 pour cent des personnes qui vivent avec le VIH connaissent leur statut sérologique. Cependant, en 2020, on estimait encore à 6 millions le nombre de personnes séropositives non diagnostiquées da...ns le monde. Les hommes vivant dans des lieux où la prévalence du VIH est élevée et les hommes appartenant aux populations clés, tous lieux confondus, ont moins de chances de connaître leur séropositivité que les femmes. Ainsi, au niveau mondial, 78 pour cent des hommes de plus de 15 ans connaissent leur statut sérologique, contre 86 pour cent chez les femmes de cette même tranche d’âge.
more
Leptospirosis is a bacterial zoonotic disease of worldwide importance, though relatively neglected in many African countries including sub Saharan Africa that is among areas with high burden of this disease. The disease is often mistaken for other febrile illnesses such as dengue, malaria, rickettsi...oses and enteric fever. Leptospirosis is an occupational disease likely to affect people working in environments prone to infestation with rodents which are the primary reservoir hosts of this disease. Some of the populations at risk include: sugarcane plantation workers, wetland farmers, fishermen and abattoir workers. In this study we investigated the prevalence of antibodies against Leptospira among sugarcane plantation and factory workers, fishing communities as well as among rodents and shrews in domestic and peridomestic environments within the study areas.
more
The objective of this concept note and the framework it outlines is the elimination of a group of CDs and the negative health effects they generate, which together create a tangible burden on affected individuals, their families and communities, and on health care systems throughout the Region. Thou...gh there is no unified consensus on the best measures to use for the public’s health and a nation’s epidemiologic situation, it is common for the disease burden to be measured by disease rates (incidence, prevalence, etc.), disease-specific death rates, comparative morbidity and mortality rates, geographic distribution, and disability-adjusted life years (DALYs). The current epidemiological situation, including data on disease rates or geographic distribution for the diseases in Table 1, is discussed below in Section 4. Hotez et al. (2008) were the first to review and compare the burden of DALYs in Latin America and the Caribbean—for NTDs, HIV/AIDS, malaria, and TB—as it existed about 10 years ago. Though the regional burden of TB, malaria, and neglected infectious diseases (NIDs) is somewhat less than it was 10 years ago, work (and schooling) continue to be lost to illness and premature death or disability, and the need for stepping up disease elimination efforts is evident in all communities living in vulnerable conditions....
more
Soil-transmitted helminths (STH) affect 1.45 billion people worldwide, and high intensity infections are associated with anemia, undernutrition and impaired cognition, particularly among children. Mathematical models suggest it may be possible to interrupt the transmission of STH in a community by e...xpanding mass drug administration (MDA) from targeted high-risk groups (primarily school-aged children and women of child-bearing age) to all community members with high coverage. The DeWorm3 Project will test the feasibility of this approach to interrupting the transmission of STH using a series of cluster randomized trials in Benin, India and Malawi. Each study area (population 80,000) will be divided into 40 clusters and randomized to community-wide or standard-of-care targeted MDA for three years. Two years following the final round of MDA, prevalence of STH will be compared between arms and transmission interruption assessed in each cluster. The DeWorm3 trials will provide stakeholders with information regarding the potential to switch from STH control to a more ambitious and sustainable strategy.
more
A group of enzootic and zoonotic protozoan infections, the leishmaniases constitute among the most severely neglected tropical diseases (NTDs) and are found in all continents except Oceania. Representing the most common infectious diseases, NTDs comprise an open-ended list of some 20 parasitic, bact...erial, viral, protozoan and helminthic infections. Called “diseases of the poor,” because of their characteristic prevalence in poor populations regardless of a country's income status, they infect over one billion people in over 140 countries, with about 90% of the global burden in Africa. While NTDs do not contribute significantly to global deaths, they are debilitating and remain the most common infections among the poor worldwide, preventing them from escaping poverty by impacting livelihoods such as agriculture and livestock, and affecting cognitive, developmental and education outcomes.
more
Visceral leishmaniasis is an important disease in East Africa where recurrent outbreaks occur. Leishmania-HIV coinfected people have high chance of developing the full-blown clinical disease, and high relapse and mortality rates. Poverty, malnutrition and population movements in endemic areas increa...se the risk of developing VL. Early diagnosis and effective prompt treatment reduce the prevalence of the disease and prevents disabilities and death. This course aims at providing health workers with the necessary knowledge to understand the epidemiology, diagnosis, treatment, surveillance and outbreak investigation of this important disease in East Africa.
more
Background: The human helminth infections include ascariasis, trichuriasis, hookworm infections, schistosomiasis, lymphatic filariasis (LF) and onchocerciasis. It is estimated that almost 2 billion people worldwide are infected with helminths. Whilst the WHO treatment guidelines for helminth infecti...ons are mostly aimed at controlling morbidity, there has been a recent shift with some countries moving towards goals of disease elimination through mass drug administration, especially for LF and onchocerciasis. However, as prevalence is driven lower, treating entire populations may no longer be the most efficient or cost-effective strategy. Instead, it may be beneficial to identify individuals or demographic groups who are persistently infected, often termed as being “predisposed” to infection, and target treatment at them.
Methods: The authors searched Embase, MEDLINE, Global Health, and Web of Science for all English language, humanbased papers investigating predisposition to helminth infections published up to October 31st, 2017. The varying definitions used to describe predisposition, and the statistical tests used to determine its presence, are summarised. Evidence for predisposition is presented, stratified by helminth species, and risk factors for predisposition to infection are identified and discussed.
Results: In total, 43 papers were identified, summarising results from 34 different studies in 23 countries. Consistent evidence of predisposition to infection with certain species of human helminth was identified. Children were regularly found to experience greater predisposition to Ascaris lumbricoides, Schistosoma mansoni and S. haematobium than adults. Females were found to be more predisposed to A. lumbricoides infection than were males. Household clustering of infection was identified for A. lumbricoides, T. trichiura and S. japonicum. Ascaris lumbricoides and T. trichiura also showed evidence of familial predisposition. Whilst strong evidence for predisposition to hookworm infection was identified, findings with regards to which groups were affected were considerably more varied than for other helminth species.
Conclusion: This review has found consistent evidence of predisposition to heavy (and light) infection for certain human helminth species. However, further research is needed to identify reasons for the reported differences between demographic groups. Molecular epidemiological methods associated with whole genome sequencing to determine ‘who infects whom’ may shed more light on the factors generating predisposition.
more
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.
more
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.
more
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.
more