5,070 results match your criteria Onchocerciasis


Strengthening data collection for neglected tropical diseases: What data are needed for models to better inform tailored intervention programmes?

PLoS Negl Trop Dis 2021 May 13;15(5):e0009351. Epub 2021 May 13.

Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom.

Locally tailored interventions for neglected tropical diseases (NTDs) are becoming increasingly important for ensuring that the World Health Organization (WHO) goals for control and elimination are reached. Mathematical models, such as those developed by the NTD Modelling Consortium, are able to offer recommendations on interventions but remain constrained by the data currently available. Data collection for NTDs needs to be strengthened as better data are required to indirectly inform transmission in an area. Read More

View Article and Full-Text PDF

The impact of mass drug administration expansion to low onchocerciasis prevalence settings in case of connected villages.

PLoS Negl Trop Dis 2021 May 12;15(5):e0009011. Epub 2021 May 12.

Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.

Background: The existence of locations with low but stable onchocerciasis prevalence is not well understood. An often suggested yet poorly investigated explanation is that the infection spills over from neighbouring locations with higher infection densities.

Methodology: We adapted the stochastic individual based model ONCHOSIM to enable the simulation of multiple villages, with separate blackfly (intermediate host) and human populations, which are connected through the regular movement of the villagers and/or the flies. Read More

View Article and Full-Text PDF

Natural Products That Changed Society.

Biomedicines 2021 Apr 26;9(5). Epub 2021 Apr 26.

The Museum of Natural Medicine & The Pharmacognostic Collection, University of Copenhagen, DK-2100 Copenhagen, Denmark.

Until the end of the 19th century all drugs were natural products or minerals. During the 19th century chemists succeeded in isolating pure natural products such as quinine, morphine, codeine and other compounds with beneficial effects. Pure compounds enabled accurate dosing to achieve serum levels within the pharmacological window and reproducible clinical effects. Read More

View Article and Full-Text PDF

Scaling-down mass ivermectin treatment for onchocerciasis elimination: modelling the impact of the geographical unit for decision making.

Clin Infect Dis 2021 Apr 28. Epub 2021 Apr 28.

London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK.

Background: Due to spatial heterogeneity in onchocerciasis transmission, the duration of ivermectin mass drug administration (MDA) required for eliminating onchocerciasis will vary within endemic areas and the occurrence of transmission 'hotspots' is inevitable. The geographical scale at which stop-MDA decisions are made will be a key driver in how rapidly national programmes can scale down active intervention upon achieving the epidemiological targets for elimination.

Methods: We use two onchocerciasis models (EPIONCHO-IBM and ONCHOSIM) to predict the likelihood of achieving elimination by 2030 in Africa, accounting for variation in pre-intervention endemicity levels and histories of ivermectin treatment. Read More

View Article and Full-Text PDF

Unusual localization of blood-borne Loa loa microfilariae in the skin depends on microfilarial density in the blood: Implications for onchocerciasis diagnosis in co-endemic areas.

Clin Infect Dis 2021 Apr 28. Epub 2021 Apr 28.

Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), Yaoundé, Cameroon.

Background: The diagnostic gold standard for onchocerciasis relies on identification and enumeration of (skin-dwelling) Onchocerca volvulus microfilariae (mf) using the skin snip technique (SST). In a recent study, blood-borne Loa loa mf were found by SST in individuals heavily infected with L. loa, and microscopically misidentified as O. Read More

View Article and Full-Text PDF

Survey design to monitor drug efficacy for the control of soil-transmitted helminthiasis and schistosomiasis.

Clin Infect Dis 2021 Apr 27. Epub 2021 Apr 27.

Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark.

Background: Control of soil-transmitted helminthiasis and schistosomiasis relies heavily on regular preventive chemotherapy. Monitoring drug efficacy is crucial to provide early warning of treatment failures. The World Health Organization (WHO) recommends a survey design in which only egg-positive individuals are retested after treatment. Read More

View Article and Full-Text PDF

Baseline Mapping of Neglected Tropical Diseases in Africa: The Accelerated WHO/AFRO Mapping Project.

Am J Trop Med Hyg 2021 Apr 26. Epub 2021 Apr 26.

7The Taskforce for Global Health, Decatur, Georgia.

Mapping is a prerequisite for effective implementation of interventions against neglected tropical diseases (NTDs). Before the accelerated WHO/AFRO NTD Mapping Project was initiated in 2014, mapping efforts in many countries were frequently carried out in an ad hoc and nonstandardized fashion. In 2013, there were at least 2,200 different districts (of the 4,851 districts in the WHO African region) that still required mapping, and in many of these districts, more than one disease needed to be mapped. Read More

View Article and Full-Text PDF

Supporting drug development for neglected tropical diseases using mathematical modelling.

Clin Infect Dis 2021 Apr 24. Epub 2021 Apr 24.

MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology and London Centre for Neglected Tropical Disease Research, Imperial College London, UK.

Drug-based interventions are at the heart of global efforts to reach elimination as a public health problem (trachoma, soil-transmitted helminthiases, schistosomiasis, lymphatic filariasis) or elimination of transmission (onchocerciasis) for five of the most prevalent neglected tropical diseases tackled via the World Health Organization preventive chemotherapy strategy. While for some of these diseases there is optimism that currently available drugs will be sufficient to achieve the proposed elimination goals, for others-particularly onchocerciasis-there is a growing consensus that novel therapeutic options will be needed. Since in this area no high return of investment is possible, minimizing wasted money and resources is essential. Read More

View Article and Full-Text PDF

Occupational use of agrochemicals results in inhibited cholinesterase activity and altered reproductive hormone levels in male farmers from Buea, Cameroon.

Toxicol Res (Camb) 2021 Mar 15;10(2):232-248. Epub 2021 Feb 15.

Laboratory for Drugs and Molecular Diagnostics Research (ANDI Centre of Excellence for Onchocerciasis Drug Research), Biotechnology Unit, University of Buea, P.O. Box 63, Buea, Cameroon.

The efficiency of agro pesticides and fertilizers in eliminating pests and scaling up crop yield has motivated farmers to increase their use. Unfortunately, health hazards caused on farmers by these agrochemicals are of growing concern, though not well elucidated. In order to evaluate the effects of occupational exposure to agrochemicals on some key parameters of male farmers' health in Buea Subdivision, Cameroon, a total of 101 men, including 62 farmers using the agrochemicals and a reference population of 39 men not involved in occupational utilization of the agrochemicals, were interviewed on use of protective equipment, exposure symptoms and reproductive health status. Read More

View Article and Full-Text PDF

Impacts of ivermectin mass drug administration for onchocerciasis on mosquito populations of Ogun state, Nigeria.

Parasit Vectors 2021 Apr 20;14(1):212. Epub 2021 Apr 20.

Department of Pure and Applied Zoology, Federal University of Agriculture, Abeokuta, Ogun, Nigeria.

Background: The impact of single-dose mass drug administration (MDA) of ivermectin for onchocerciasis on mosquito populations was investigated in Ogun State, Nigeria.

Methods: Indoor and outdoor collection of mosquitoes was carried out in two intervention (IC) and two control communities (CC) at three different periods: pre-MDA (baseline), 2-3 days after MDA and 13-14 days after MDA. The density and parity rate of female Anopheles and Culex mosquitoes were determined and compared. Read More

View Article and Full-Text PDF

Evaluation of macrofilaricidal and microfilaricidal activities against Onchocerca ochengi and cytotoxicity of some synthesized azo compounds containing thiophene backbone.

Parasitol Res 2021 Apr 17. Epub 2021 Apr 17.

Department of Biochemistry and Molecular Biology, University of Buea, P.O. Box 63, Buea, South West Region, Cameroon.

Control and treatment of onchocerciasis, a devastating tropical filarial disease caused by Onchocerca volvulus, rely solely on the community directed treatment with ivermectin. However, ivermectin is only microfilaricidal with evidence of resistance of the parasite among other limitations, which necessitate the search for new efficacious and safe filaricides. Ten synthetic thienylazoryl dyes were screened in vitro against adult and microfilariae worm stages of Onchocerca ochengi based on worm motility and MTT formazan assay. Read More

View Article and Full-Text PDF

Compliance to a Five-Year Biannual Ivermectin Treatment for Onchocerciasis Elimination and Its Determinants among Adults in the Bench Maji Zone, Southwest Ethiopia: A Community-Based Cross-Sectional Study.

J Parasitol Res 2021 29;2021:8866639. Epub 2021 Mar 29.

Jimma University, Institute of Health, Public Health Faculty, Epidemiology Department, Ethiopia.

Background: Community-directed treatment with ivermectin twice a year is a major action to control onchocerciasis in endemic countries. Even though the community-directed treatment with ivermectin was proven effective in treating the disease, the level of compliance to the treatment and its contributing factors was not well addressed in our study area. Therefore, the current study was aimed at determining the magnitude of compliance with the five-year (2013-2017 years) biannual ivermectin treatment and its associated factors among adults living in the Bench Maji Zone, Ethiopia. Read More

View Article and Full-Text PDF

Autochthonous, zoonotic Onchocerca lupi in a South Texas dog, United States.

Parasit Vectors 2021 Apr 15;14(1):203. Epub 2021 Apr 15.

Texas A&M Veterinary Medical Diagnostic Laboratory, College Station, TX, USA.

Background: Onchocerca lupi is an emerging, zoonotic filarioid nematode associated with ocular disease in companion animals in North America and the Old World. The areas where this parasite is assumed to be endemic in the USA comprise southwestern states. Thus far, all cases reported outside of the southwest are associated with travel or animal movement. Read More

View Article and Full-Text PDF

Preventive chemotherapy for the control of strongyloidiasis in school-age children: Estimating the ivermectin need.

PLoS Negl Trop Dis 2021 Apr 15;15(4):e0009314. Epub 2021 Apr 15.

Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Verona, Italy.

Background: Strongyloides stercoralis is a soil-transmitted helminth (STH) that affects approximately 600 million people worldwide. Interventions targeting S. stercoralis have not been implemented yet. Read More

View Article and Full-Text PDF

Canine ocular onchocerciasis in New Mexico: Risk factors for disease.

Vet Ophthalmol 2021 Apr 9. Epub 2021 Apr 9.

Department of Biology, University of New Mexico, Albuquerque, NM, USA.

Objective: To determine whether dogs are at variable risk of developing canine ocular onchocerciasis based on coat color or size, factors that may influence feeding behavior of the putative vectors of Onchocerca lupi¸ the filarial nematode parasite causing this disease.

Animals Studied: One hundred twenty-five client-owned dogs diagnosed with confirmed or suspected onchocerciasis. 1255 dogs without signs of this disease were utilized for comparison. Read More

View Article and Full-Text PDF

Onchocerciasis Prevalence among Persons with Epilepsy in an Onchocerciasis Hypo-Endemic Area in the Democratic Republic of Congo: A Cross-Sectional Study.

Pathogens 2021 Mar 24;10(4). Epub 2021 Mar 24.

Global Health Institute, University of Antwerp, 2100 Antwerp, Belgium.

A high epilepsy prevalence has been reported in onchocerciasis meso- and hyper-endemic regions in sub-Saharan Africa, including in the Democratic Republic of Congo (DRC). We investigated whether onchocerciasis-associated epilepsy can also be suspected in onchocerciasis hypo-endemic regions. Stored serum samples from 342 patients admitted with recent onset neurological symptoms admitted to Mosango general hospital, in the Kwilu province, DRC, between 2012 and 2015 were screened for onchocerciasis (OV16) antibodies by ELISA and antigen (using an in-house B158/B60 antigen test). Read More

View Article and Full-Text PDF

Potential Parasitic Causes of Epilepsy in an Onchocerciasis Endemic Area in the Ituri Province, Democratic Republic of Congo.

Pathogens 2021 Mar 18;10(3). Epub 2021 Mar 18.

Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium.

A high burden of epilepsy is observed in Africa where parasitological infections are endemic. In 2016, in an Onchocerciasis endemic area in the Logo health zone, in Ituri province in the Democratic Republic of Congo, a door-to-door study showed an epilepsy prevalence of 4.6%, and 50. Read More

View Article and Full-Text PDF

Cytokines and Onchocerciasis-Associated Epilepsy, a Pilot Study and Review of the Literature.

Pathogens 2021 Mar 7;10(3). Epub 2021 Mar 7.

Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium.

Neuro-inflammation may be associated with onchocerciasis-associated epilepsy (OAE) but thus far very few immunological studies have been performed in children with this form of epilepsy. In a pilot study we measured the cytokine levels in cerebrospinal fluid (CSF) of persons with OAE from Maridi, South Sudan, and from Mosango, Democratic Republic of the Congo (DRC) and compared these results with cytokine levels in CSF of Africans with non-OAE neurological disorders, and Europeans with epilepsy or other neurological conditions. The following cytokines were studied: IL-6, TNF-α, IL1-β, IL-5, IL-4, IL-13, CCL3 (Mip-1α), VEGF-C, VCAM-1. Read More

View Article and Full-Text PDF

Efficacy and safety of ascending doses of moxidectin against Strongyloides stercoralis infections in adults: a randomised, parallel-group, single-blinded, placebo-controlled, dose-ranging, phase 2a trial.

Lancet Infect Dis 2021 Mar 30. Epub 2021 Mar 30.

Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland. Electronic address:

Background: Strongyloidiasis represents a major public health issue, particularly in resource-limited countries. Preliminary studies suggest that moxidectin might serve as an alternative to the only available treatment option, ivermectin. We aimed to evaluate the efficacy and safety of ascending doses of moxidectin in Strongyloides stercoralis-infected patients. Read More

View Article and Full-Text PDF

COVID-19: The Ivermectin African Enigma.

Colomb Med (Cali) 2020 Dec 30;51(4):e2014613. Epub 2020 Dec 30.

Barbara&Frick. Bogotá. Colombia.

Introduction: The low frequency of cases and deaths from the SARS-CoV-2 COVID-19 virus in some countries of Africa has called our attention about the unusual behavior of this disease. The ivermectin is considered a drug of choice for various parasitic and viral diseases and shown to have in vitro effects against SARS-CoV-2.

Aims: Our study aimed to describe SARS-CoV2 infection and death rates in African countries that participated in an intensive Ivermectin mass campaign carried out to control onchocerciasis and compare them with those of countries that did not participate. Read More

View Article and Full-Text PDF
December 2020

Complex emergencies and the control and elimination of neglected tropical diseases in Africa: developing a practical approach for implementing safe and effective mapping and intervention strategies.

Confl Health 2021 Mar 31;15(1):18. Epub 2021 Mar 31.

Sightsavers, Haywards Heath, UK.

Background: Complex emergencies resulting from conflict and political instability are a major challenge for national neglected tropical diseases (NTDs) control and elimination programmes, especially in sub-Saharan Africa. Currently, there are no formal guidelines for national programmes to use and plan activities in these humanitarian situations, therefore the aim of this study was to develop a new methodological approach for making decisions about the implementation of safe and effective mapping and mass drug administration (MDA) intervention strategies.

Methods: The study focussed on the 47 World Health Organization's African Region (AFR) countries. Read More

View Article and Full-Text PDF

Attendee's awareness about preventive chemotherapy neglected tropical diseases (PC-NTD) control during the first world neglected tropical diseases day in Ekiti State, Nigeria.

PLoS Negl Trop Dis 2021 Mar 29;15(3):e0009315. Epub 2021 Mar 29.

Department of Pure and Applied Zoology, Federal University of Agriculture, Abeokuta, Nigeria.

Background: The need to control Neglected Tropical Diseases (NTDs) and sustain progress towards elimination through mass administration of medicines requires substantial communal participation. This study, therefore, assessed the knowledge and perception of attendees' regarding NTDs and its control activities during the inaugural World NTD day event in Ekiti State, Nigeria.

Methodology: A cross-sectional study involving the administration of pretested semi-structured questionnaires to consenting attendees at the Inaugural World NTD day event was conducted on the 30th January, 2020. Read More

View Article and Full-Text PDF

Safety, tolerability and pharmacokinetics of emodepside, a potential novel treatment for onchocerciasis (river blindness), in healthy male subjects.

Br J Clin Pharmacol 2021 Mar 24. Epub 2021 Mar 24.

Bayer AG, Wuppertal, Germany.

Aims: Emodepside is an anthelmintic, originally developed for veterinary use. We investigated in healthy subjects the safety, and pharmacokinetics of a liquid service formulation (LSF) and immediate release (IR) tablet of emodepside in 2 randomised, parallel-group, placebo-controlled, Phase I studies.

Methods: Seventy-nine subjects in 10 cohorts in the single ascending dose study and 24 subjects in 3 ascending-dose cohorts in the multiple ascending dose study were enrolled. Read More

View Article and Full-Text PDF

Morinda lucida Benth (Rubiaceae): A review of its ethnomedicine, phytochemistry and pharmacology.

J Ethnopharmacol 2021 Mar 19;276:114055. Epub 2021 Mar 19.

Department of Biochemistry, University of Ilorin, Ilorin, Nigeria. Electronic address:

Ethnomedicinal Relevance: Natural products derived from plants have served the primary healthcare needs of millions of indigenous people for centuries, many of which have been documented and scientifically validated. Morinda lucida Benth (Rubiaceae), also referred to as brimstone tree, is an ethnomedicinal plant which has been widely used in traditional medicine for several decades, particularly in the African continent. Various parts of the plant, including stem bark, leaves and root, have been applied in traditional medicine for the management of various pathological conditions such as malaria, diabetes, hypertension, inflammation, typhoid fever, cancer, cognitive disorders, sickle cell disease, trypanosomiasis, onchocerciasis and various fevers. Read More

View Article and Full-Text PDF

Socio-cultural factors in onchocerciasis control: a study of rural Southeast Nigeria.

J Parasit Dis 2021 Mar 10;45(1):10-16. Epub 2020 Sep 10.

Department of Sociology, Imo State University, P.M.B. 2000, Owerri, Imo State Nigeria.

Despite significant global and local efforts geared towards elimination of onchocerciasis, it has been observed that there are socio-cultural factor that make the disease to persist; especially in the rural areas.This study, therefore, investigated socio-cultural factors influencing the control of onchocerciasis in rural southeast Nigeria. The mixed methods research design was adopted for this study. Read More

View Article and Full-Text PDF

Community-directed distributors-The "foot soldiers" in the fight to control and eliminate neglected tropical diseases.

PLoS Negl Trop Dis 2021 03 4;15(3):e0009088. Epub 2021 Mar 4.

Onchocerciasis Control Programme in West Africa, World Health Organization, Accra, Ghana.

The neglected tropical diseases (NTDs) affect hundreds of millions of people, predominantly in rural, often difficult-to-access areas, poorly served by national health services. Here, we review the contributions of 4.8 million community-directed distributors (CDDs) of medicines over 2 decades in 146,000 communities in 27 sub-Saharan African countries to control or eliminate onchocerciasis and lymphatic filariasis (LF). Read More

View Article and Full-Text PDF

The impact of ivermectin on onchocerciasis in villages co-endemic for lymphatic filariasis in an area of onchocerciasis recrudescence in Burkina Faso.

PLoS Negl Trop Dis 2021 Mar 1;15(3):e0009117. Epub 2021 Mar 1.

Medical Entomologist (Freelance), Ouagadougou, Burkina Faso.

In Burkina Faso, onchocerciasis was no longer a public health problem when the WHO Onchocerciasis Control Programme in West Africa closed at the end in 2002. However, epidemiological surveillance carried out from November 2010 to February of 2011, showed a recrudescence of infection in the Cascades Region. This finding was made at a time when ivermectin, a drug recommended for the treatment of both onchocerciasis and lymphatic filariasis, had been distributed in this area since 2004 for the elimination of lymphatic filariasis. Read More

View Article and Full-Text PDF

The Eagle effect in the Wolbachia-worm symbiosis.

Parasit Vectors 2021 Feb 24;14(1):118. Epub 2021 Feb 24.

Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA.

Background: Onchocerciasis (river blindness) and lymphatic filariasis (elephantiasis) are two human neglected tropical diseases that cause major disabilities. Mass administration of drugs targeting the microfilarial stage has reduced transmission and eliminated these diseases in several countries but a macrofilaricidal drug that kills or sterilizes the adult worms is critically needed to eradicate the diseases. The causative agents of onchocerciasis and lymphatic filariasis are filarial worms that harbor the endosymbiotic bacterium Wolbachia. Read More

View Article and Full-Text PDF
February 2021

Infectious diseases among Ethiopian immigrants in Israel: a descriptive literature review.

Pathog Glob Health 2021 Feb 24:1-11. Epub 2021 Feb 24.

Department of Family Medicine and Siaal Research Center for Family Practice and Primary Care, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.

The mass immigration of Ethiopian Jews to Israel began in the 1980s. For most of these immigrants this was a time of sharp transition from a village life with very basic living conditions, in most cases without a regular supply of water, electricity, or healthcare services, to a modern Western urban society. The aim of this review was to search the medical literature on the characteristics of infectious diseases that are typical in Ethiopian immigrants (EI), using relevant keywords. Read More

View Article and Full-Text PDF
February 2021

In pursuit of a cure: The plural therapeutic landscape of onchocerciasis-associated epilepsy in Cameroon - A mixed methods study.

PLoS Negl Trop Dis 2021 Feb 23;15(2):e0009206. Epub 2021 Feb 23.

Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.

Background: A high prevalence of epilepsy has been observed in several onchocerciasis-endemic villages in the Sanaga River basin, Cameroon. Recent studies suggest that ivermectin, a drug that is distributed annually with the aim of eliminating onchocerciasis, may have a protective effect against acquiring onchocerciasis-associated epilepsy (OAE). This study, therefore, provides an in-depth understanding of both the complex therapeutic landscape for epilepsy as well as the experiences related to the 'community-directed treatment with ivermectin' (CDTI) campaign in order to identify a more trenchant path forward in the fight against epilepsy. Read More

View Article and Full-Text PDF
February 2021