1
|
Hildebrandt TR, Davi SD, Kabwende AL, Endamne LR, Mehmel E, Rakotonirinalalao M, Alabi A, Manego RZ, Kremsner PG, Lell B, Adegnika AA, Mombo-Ngoma G, Mischlinger J, Agnandji ST, Ramharter M. Evaluation of knowledge, attitude and practice towards loiasis in the rural community of Sindara, in central African Gabon. PLoS Negl Trop Dis 2024; 18:e0012109. [PMID: 38781277 DOI: 10.1371/journal.pntd.0012109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 03/27/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND More than 20 million people are infected with L. loa, and around 40 million live in high or intermediate-risk areas in West- and Central Africa. Although loiasis is associated with significant morbidity and excess mortality, little is known about the perception of loiasis by affected communities. This study assessed the knowledge, attitudes, and practices in the rural population of Sindara, Gabon, a region characterized by high loiasis prevalence. METHODS A community-based cross-sectional survey was conducted in Gabon between January and June 2022. During systematic door-to-door visits, randomly selected inhabitants were invited to participate in this questionnaire based survey. Venous blood was collected at midday from all participants for microscopic detection of filarial infection and clinical signs of loiasis were assessed. RESULTS A total of 150 participants were recruited, of which 66% were infected by L. loa. While almost everyone had some knowledge about L. loa, 72% of the participants understood that L. loa is a parasitic worm. The transmission of L. loa via the deer fly was known to only 21% of participants. The most frequently mentioned clinical symptoms attributed to loiasis were itching (84%), eye worm migration (59%), and conjunctivitis-like symptoms (53%). Participants who experienced migratory loiasis had better knowledge of loiasis and considered it as more serious. Traditional and herbal medicine was reported most often as an available treatment option (72%). While the formal healthcare sector was mentioned as the preferred treatment provider, 60% of the reported infections were treated by traditional medical practitioners. CONCLUSION Loiasis is in general well known by this community residing in a region of high L. loa transmission. Important gaps in knowledge were discovered foremost regarding the mode of transmission. The available healthcare system does not seem to provide adequate management for loiasis.
Collapse
Affiliation(s)
- Teite Rebecca Hildebrandt
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Saskia Dede Davi
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | | | - Lilian Rene Endamne
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Esther Mehmel
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Maximilian Rakotonirinalalao
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Ayodele Alabi
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Rella Zoleko Manego
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Peter G Kremsner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Medical University of Vienna, Vienna, Austria
| | - Ayôla Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
- German Center for Infection Research, Partner Site Tübingen, Germany
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Johannes Mischlinger
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Michael Ramharter
- Center for Tropical Medicine, Bernhard-Nocht Institute for Tropical Medicine and I. Department of Medicine University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research, Partner Sites Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| |
Collapse
|
2
|
Ramharter M, Butler J, Mombo-Ngoma G, Nordmann T, Davi SD, Zoleko Manego R. The African eye worm: current understanding of the epidemiology, clinical disease, and treatment of loiasis. THE LANCET. INFECTIOUS DISEASES 2024; 24:e165-e178. [PMID: 37858326 DOI: 10.1016/s1473-3099(23)00438-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 10/21/2023]
Abstract
Loa loa, the African eye worm, is a filarial pathogen transmitted by blood-sucking flies of the genus Chrysops. Loiasis primarily affects rural populations residing in the forest and adjacent savannah regions of central and west Africa, where more than 20 million patients are chronically infected in medium and high transmission regions. For a long time, loiasis has been regarded as a relatively benign condition. However, morbidity as measured by disability-adjusted life-years lost might be as high as 400 per 100 000 residents, and the population attributable fraction of death is estimated at 14·5% in highly endemic regions, providing unequivocal evidence for the substantial disease burden that loiasis exerts on affected communities. The clinical penetrance of loiasis is variable and might present with the classic signs of eye worm migration or transient Calabar swellings, but might include common, unspecific symptoms or rare but potentially life-threatening complications. Although adult worm migration seems most closely linked to symptomatic disease, high levels of microfilaraemia are associated with clinically important complications and death. Loiasis remains difficult to diagnose, treat, and control due to an absence of reliable point-of-care diagnostic assays, safe and efficacious drugs, and cost-effective prevention strategies. This Review summarises the major advances in our understanding of loiasis made over the past decade and highlights the many gaps that await to be addressed urgently.
Collapse
Affiliation(s)
- Michael Ramharter
- Department of Clinical Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Division of Tropical Medicine, I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Centre de Recherche Médicale de Lambaréné, Lambaréné, Gabon; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany.
| | | | - Ghyslain Mombo-Ngoma
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Division of Tropical Medicine, I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Centre de Recherche Médicale de Lambaréné, Lambaréné, Gabon; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Tamara Nordmann
- Department of Clinical Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Division of Tropical Medicine, I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Saskia Dede Davi
- Department of Clinical Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Division of Tropical Medicine, I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Rella Zoleko Manego
- Department of Clinical Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Division of Tropical Medicine, I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Centre de Recherche Médicale de Lambaréné, Lambaréné, Gabon
| |
Collapse
|
3
|
Cadavid Restrepo AM, Martin BM, Fuimaono S, Clements ACA, Graves PM, Lau CL. Spatial predictive risk mapping of lymphatic filariasis residual hotspots in American Samoa using demographic and environmental factors. PLoS Negl Trop Dis 2023; 17:e0010840. [PMID: 37486947 PMCID: PMC10399813 DOI: 10.1371/journal.pntd.0010840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 06/26/2023] [Indexed: 07/26/2023] Open
Abstract
BACKGROUND American Samoa successfully completed seven rounds of mass drug administration (MDA) for lymphatic filariasis (LF) from 2000-2006. The territory passed the school-based transmission assessment surveys in 2011 and 2015 but failed in 2016. One of the key challenges after the implementation of MDA is the identification of any residual hotspots of transmission. METHOD Based on data collected in a 2016 community survey in persons aged ≥8 years, Bayesian geostatistical models were developed for LF antigen (Ag), and Wb123, Bm14, Bm33 antibodies (Abs) to predict spatial variation in infection markers using demographic and environmental factors (including land cover, elevation, rainfall, distance to the coastline and distance to streams). RESULTS In the Ag model, females had a 26.8% (95% CrI: 11.0-39.8%) lower risk of being Ag-positive than males. There was a 2.4% (95% CrI: 1.8-3.0%) increase in the odds of Ag positivity for every year of age. Also, the odds of Ag-positivity increased by 0.4% (95% CrI: 0.1-0.7%) for each 1% increase in tree cover. The models for Wb123, Bm14 and Bm33 Abs showed similar significant associations as the Ag model for sex, age and tree coverage. After accounting for the effect of covariates, the radii of the clusters were larger for Bm14 and Bm33 Abs compared to Ag and Wb123 Ab. The predictive maps showed that Ab-positivity was more widespread across the territory, while Ag-positivity was more confined to villages in the north-west of the main island. CONCLUSION The findings may facilitate more specific targeting of post-MDA surveillance activities by prioritising those areas at higher risk of ongoing transmission.
Collapse
Affiliation(s)
- Angela M Cadavid Restrepo
- School of Public Health, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Beatris M Martin
- School of Public Health, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | | | - Archie C A Clements
- Curtin School of Population Health, Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia
| | - Patricia M Graves
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, Queensland, Australia
| | - Colleen L Lau
- School of Public Health, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| |
Collapse
|
4
|
Anisuzzaman, Hossain MS, Hatta T, Labony SS, Kwofie KD, Kawada H, Tsuji N, Alim MA. Food- and vector-borne parasitic zoonoses: Global burden and impacts. ADVANCES IN PARASITOLOGY 2023; 120:87-136. [PMID: 36948728 DOI: 10.1016/bs.apar.2023.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Abstract
Around 25% of the global population suffer from one or more parasitic infections, of which food- and vector-borne parasitic zoonotic diseases are a major concern. Additionally, zoonoses and communicable diseases, common to man and animals, are drawing increased attention worldwide. Significant changes in climatic conditions, cropping pattern, demography, food habits, increasing international travel, marketing and trade, deforestation, and urbanization play vital roles in the emergence and re-emergence of parasitic zoonoses. Although it is likely to be underestimated, the collective burden of food- and vector-borne parasitic diseases accounts for ∼60 million disability-adjusted life years (DALYs). Out of 20 neglected tropical diseases (NTDs) listed by the World Health Organization (WHO) and the Centres for Disease Control and Prevention (CDC), 13 diseases are of parasitic origin. There are about 200 zoonotic diseases of which the WHO listed eight as neglected zoonotic diseases (NZDs) in the year 2013. Out of these eight NZDs, four diseases, namely cysticercosis, hydatidosis, leishmaniasis, and trypanosomiasis, are caused by parasites. In this review, we discuss the global burden and impacts of food- and vector-borne zoonotic parasitic diseases.
Collapse
Affiliation(s)
- Anisuzzaman
- Department of Parasitology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh.
| | - Md Shahadat Hossain
- Department of Parasitology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Takeshi Hatta
- Department of Parasitology and Tropical Medicine, Kitasato University School of Medicine, Minami, Sagamihara, Kanagawa, Japan
| | - Sharmin Shahid Labony
- Department of Parasitology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Kofi Dadzie Kwofie
- Department of Parasitology and Tropical Medicine, Kitasato University School of Medicine, Minami, Sagamihara, Kanagawa, Japan; Department of Parasitology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Hayato Kawada
- Department of Parasitology and Tropical Medicine, Kitasato University School of Medicine, Minami, Sagamihara, Kanagawa, Japan
| | - Naotoshi Tsuji
- Department of Parasitology and Tropical Medicine, Kitasato University School of Medicine, Minami, Sagamihara, Kanagawa, Japan.
| | - Md Abdul Alim
- Department of Parasitology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| |
Collapse
|
5
|
Wong ML, Zulzahrin Z, Vythilingam I, Lau YL, Sam IC, Fong MY, Lee WC. Perspectives of vector management in the control and elimination of vector-borne zoonoses. Front Microbiol 2023; 14:1135977. [PMID: 37025644 PMCID: PMC10070879 DOI: 10.3389/fmicb.2023.1135977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 02/28/2023] [Indexed: 04/08/2023] Open
Abstract
The complex transmission profiles of vector-borne zoonoses (VZB) and vector-borne infections with animal reservoirs (VBIAR) complicate efforts to break the transmission circuit of these infections. To control and eliminate VZB and VBIAR, insecticide application may not be conducted easily in all circumstances, particularly for infections with sylvatic transmission cycle. As a result, alternative approaches have been considered in the vector management against these infections. In this review, we highlighted differences among the environmental, chemical, and biological control approaches in vector management, from the perspectives of VZB and VBIAR. Concerns and knowledge gaps pertaining to the available control approaches were discussed to better understand the prospects of integrating these vector control approaches to synergistically break the transmission of VZB and VBIAR in humans, in line with the integrated vector management (IVM) developed by the World Health Organization (WHO) since 2004.
Collapse
Affiliation(s)
- Meng Li Wong
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Zulhisham Zulzahrin
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Yee Ling Lau
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - I-Ching Sam
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Medical Microbiology, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
| | - Mun Yik Fong
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Wenn-Chyau Lee
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- A*STAR Infectious Diseases Labs (A*STAR ID Labs), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- *Correspondence: Wenn-Chyau Lee,
| |
Collapse
|
6
|
Nicolini AL, Tamarozzi F, Pomari E, Mistretta M, Camera M, Sepulcri C, Bassetti M, Gobbi FG. Loiasis from where you don't expect it: an illustrative case of misled diagnosis. J Travel Med 2022; 29:6582207. [PMID: 35532187 PMCID: PMC9635057 DOI: 10.1093/jtm/taac060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 05/02/2022] [Accepted: 05/05/2022] [Indexed: 11/14/2022]
Abstract
In the absence of pathognomonic signs, the diagnosis of filarial infections relies on geographical exposure and morphology of microfilariae, which requires expertise. We present a case of loiasis in a patient not reporting exposure in areas of known Loa loa endemicity, whose diagnosis was achieved by molecular analysis of microfilariae.
Collapse
Affiliation(s)
| | - Francesca Tamarozzi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| | - Elena Pomari
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| | - Manuela Mistretta
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| | - Marco Camera
- Division of Infectious Diseases, Policlinico San Martino-IRCCS, Genoa, Italy
| | - Chiara Sepulcri
- Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
| | - Matteo Bassetti
- Division of Infectious Diseases, Policlinico San Martino-IRCCS, Genoa, Italy.,Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
| | - Federico G Gobbi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| |
Collapse
|
7
|
Integrated xenosurveillance of Loa loa, Wuchereria bancrofti, Mansonella perstans and Plasmodium falciparum using mosquito carcasses and faeces: A pilot study in Cameroon. PLoS Negl Trop Dis 2022; 16:e0010868. [PMID: 36322515 PMCID: PMC9629651 DOI: 10.1371/journal.pntd.0010868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 10/03/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Community presence of loiasis must be determined before mass drug administration programmes for lymphatic filariasis and onchocerciasis can be implemented. However, taking human blood samples for loiasis surveillance is invasive and operationally challenging. A xenosurveillance approach based on the molecular screening of mosquitoes and their excreta/feces (E/F) for Loa loa DNA may provide a non-invasive method for detecting the community presence of loiasis. METHODS We collected 770 wild mosquitoes during a pilot study in a known loiasis transmission area in Mbalmayo, Cameroon. Of these, 376 were preserved immediately while 394 were kept in pools to collect 36-hour E/F samples before processing. Carcasses and E/F were screened for L. loa DNA. To demonstrate this method's potential for integrated disease surveillance, the samples were further tested for Wuchereria bancrofti, Mansonella perstans, and Plasmodium falciparum. RESULTS Despite limited sample numbers, L. loa DNA was detected in eight immediately-stored mosquitoes (2.13%; 95% CI 1.08 to 4.14), one carcass stored after providing E/F (0.25%; 95% CI 0.04 to 1.42), and three E/F samples (estimated prevalence 0.77%; 95% CI 0.15 to 2.23%). M. perstans and P. falciparum DNA were also detected in carcasses and E/F samples, while W. bancrofti DNA was detected in E/F. None of the carcasses positive for filarial worm DNA came from pools that provided a positive E/F sample, supporting the theory that, in incompetent vectors, ingested parasites undergo a rapid, complete expulsion in E/F. CONCLUSIONS Mosquito xenosurveillance may provide a useful tool for the surveillance of loiasis alongside other parasitic diseases.
Collapse
|
8
|
Jacobsen KH, Andress BC, Bhagwat EA, Bryant CA, Chandrapu VR, Desmonts CG, Matthews TM, Ogunkoya A, Wheeler TJ, Williams AS. A call for loiasis to be added to the WHO list of neglected tropical diseases. THE LANCET. INFECTIOUS DISEASES 2022; 22:e299-e302. [PMID: 35500592 DOI: 10.1016/s1473-3099(22)00064-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 06/14/2023]
Abstract
Loiasis, also called African eye worm, is not currently on WHO's list of priority neglected tropical diseases, even though the risk that individuals with high Loa loa microfilarial densities will develop potentially fatal encephalopathy when they take ivermectin has complicated efforts to use mass drug administration for onchocerciasis (river blindness) and lymphatic filariasis control in co-endemic areas. At least 10 million residents of central and west Africa are thought to have loiasis, which causes painful and itchy subcutaneous oedema, arthralgia, and discomfort when adult helminths that are 3-7 cm in length are present under the conjunctiva of the eye. High levels of microfilaraemia are associated with renal, cardiac, neurological, and other sequelae, and an increased risk of death. The public health burden of loiasis could be greatly reduced with expanded use of diagnostic tests, anthelmintic treatment, and control of the Chrysops spp (tabanid flies) vectors that transmit the parasite. Loiasis should be added to the next revision of the WHO neglected tropical disease priority list, not merely because its inclusion will support the elimination of other skin and subcutaneous neglected tropical diseases, but also because of the complications caused by loiasis itself.
Collapse
Affiliation(s)
- Kathryn H Jacobsen
- Department of Health Studies, University of Richmond, Richmond, VA, USA.
| | - Bailey C Andress
- Department of Health Studies, University of Richmond, Richmond, VA, USA
| | - Elina A Bhagwat
- Department of Health Studies, University of Richmond, Richmond, VA, USA
| | - Ciera A Bryant
- Department of Health Studies, University of Richmond, Richmond, VA, USA
| | | | | | - Tania M Matthews
- Department of Health Studies, University of Richmond, Richmond, VA, USA
| | - Akeem Ogunkoya
- Department of Health Studies, University of Richmond, Richmond, VA, USA
| | - Tristan J Wheeler
- Department of Health Studies, University of Richmond, Richmond, VA, USA
| | | |
Collapse
|
9
|
Pallara E, Cotugno S, Guido G, De Vita E, Ricciardi A, Totaro V, Camporeale M, Frallonardo L, Novara R, Panico GG, Puzo P, Alessio G, Sablone S, Mariani M, De Iaco G, Milano E, Bavaro DF, Lattanzio R, Patti G, Papagni R, Pellegrino C, Saracino A, Di Gennaro F. Loa loa in the Vitreous Cavity of the Eye: A Case Report and State of Art. Am J Trop Med Hyg 2022; 107:tpmd220274. [PMID: 35914685 PMCID: PMC9490677 DOI: 10.4269/ajtmh.22-0274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/06/2022] [Indexed: 11/20/2022] Open
Abstract
Loa loa is a filarial nematode responsible for loiasis, endemic to West-Central Africa south of the Sahara and transmitted by flies. This study reports a case of L. loa in the vitreous cavity of the eye of a young patient, along with an in-depth literature review. A 22-year-old woman from Cameroon who migrated from Cameroon to Italy was referred to the Emergency Ophthalmology Department at Policlinico di Bari in July 2021 with the presence of a moving parasite in the subconjunctiva of the left eye. A recent onset of a papular lesion on the dorsal surface of the right wrist and a nodular lesion in the scapular region were detected. L. loa filariasis was diagnosed based on anamnestic data, clinical and paraclinical signs, and a parasitological test confirming the presence of microfilariae in two blood samples collected in the morning of two different days. Because of the unavailability of diethylcarbamazine (DEC), albendazole (ALB) 200 mg twice daily was administered for 21 days. A mild exacerbation of pruritus occurred during treatment, but resolved with the use of an antihistamine. A single dose of 12 mg ivermectin was prescribed at the end of the treatment with albendazole. Unlike other endemic parasite infections, L. loa is not included in the Global Program to Eliminate Lymphatic Filariasis, because it is not mentioned in the WHO and CDC list of neglected tropical diseases. This can result in an overall risk of lack of attention and studies on loiasis, with lack of data on global burden of the disease.
Collapse
Affiliation(s)
- Elisabetta Pallara
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Sergio Cotugno
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Giacomo Guido
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Elda De Vita
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Aurelia Ricciardi
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Valentina Totaro
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Michele Camporeale
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Luisa Frallonardo
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Roberta Novara
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Gianfranco G. Panico
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Pasquale Puzo
- Section of Ophthalmology, Department of Medical Science, Neuroscience and Senso Organs, Bari Policlinico Hospital University of Bari, Bari, Italy
| | - Giovanni Alessio
- Section of Ophthalmology, Department of Medical Science, Neuroscience and Senso Organs, Bari Policlinico Hospital University of Bari, Bari, Italy
| | - Sara Sablone
- Section of Legal Medicine, Department of Interdisciplinary Medicine, University of Bari “Aldo Moro,” Bari, Italy
| | - Michele Mariani
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Giuseppina De Iaco
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Eugenio Milano
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Davide F. Bavaro
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Rossana Lattanzio
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Giulia Patti
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Roberta Papagni
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Carmen Pellegrino
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Annalisa Saracino
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| | - Francesco Di Gennaro
- Clinic of Infectious Diseases, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro,” Bari, Italy
| |
Collapse
|
10
|
Tirados I, Thomsen E, Worrall E, Koala L, Melachio TT, Basáñez MG. Vector control and entomological capacity for onchocerciasis elimination. Trends Parasitol 2022; 38:591-604. [DOI: 10.1016/j.pt.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/17/2022] [Accepted: 03/08/2022] [Indexed: 11/24/2022]
|
11
|
Musumeci S, Ramu L, Chappuis F, Eperon G. Loiasis and diurnal microfilaremia: searching at the right moment. J Travel Med 2022; 29:6414503. [PMID: 34718684 DOI: 10.1093/jtm/taab176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/12/2021] [Accepted: 10/14/2021] [Indexed: 11/13/2022]
Abstract
A healthy young woman from Cameroon was addressed to the tropical medicine consultation of the University Hospitals of Geneva to investigate an asymptomatic eosinophilia of 1.22 G/l and a history of ‘eye worms’ during childhood. Direct microscopic observation found viable microfilariae, and the stained blood smear confirmed Loa loa species.
Collapse
|
12
|
Chagas CRF, Binkienė R, Valkiūnas G. Description and Molecular Characterization of Two Species of Avian Blood Parasites, with Remarks on Circadian Rhythms of Avian Haematozoa Infections. Animals (Basel) 2021; 11:3490. [PMID: 34944267 PMCID: PMC8698112 DOI: 10.3390/ani11123490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/02/2021] [Accepted: 12/02/2021] [Indexed: 11/23/2022] Open
Abstract
Avian blood parasites are remarkably diverse and frequently occur in co-infections, which predominate in wildlife. This makes wildlife pathogen research challenging, particularly if they belong to closely related groups, resulting in diagnostic problems and poor knowledge about such infections as well as the patterns of their co-occurrence and interactions. This is particularly true due to the periodicity (circadian rhythms) of parasitemia, which means that different parasitemia and parasite stages might be found throughout the day. We analysed blood samples from a Eurasian blackbird (Turdus merula) and a Song thrush (Turdus philomelos). This study aimed to describe a new avian Lankesterella species and molecularly characterize and redescribe Splendidofilaria mavis, a common avian filarioid nematode. Additionally, it was possible to investigate the circadian rhythms of the avian blood parasites belonging to Plasmodium, Haemoproteus, Leucocytozoon, and Trypanosoma, which occurred in co-infection in the same avian host individuals. Different circadian rhythms were seen in different parasites, with Plasmodium sp. peaks occurring at midday, Leucocytozoon spp. peaks mainly during the evening and night, and Trypanosoma spp. and microfilariae peaks at midnight. No periodicity was seen in Haemoproteus and Lankesterella species infections. The time of parasitemia peaks most likely coincides with the time of vectors' activity, and this should be beneficial for transmission. Knowledge about the circadian rhythms is needed for better understanding patterns in host-parasite interactions and disease transmission.
Collapse
|
13
|
Badia-Rius X, Betts H, Wanji S, Molyneux D, Taylor MJ, Kelly-Hope LA. Environmental Factors Associated With Loa loa Microfilaria Prevalence and Intensity in Diverse Bioecological Zones of Cameroon. FRONTIERS IN TROPICAL DISEASES 2021. [DOI: 10.3389/fitd.2021.668641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Loiasis (African Eye Worm) is a filarial infection caused by Loa loa and transmitted by Chrysops vectors, which are confined to the tropical rainforests of Central and West Africa. Loiasis is a major impediment to control and elimination programmes that use the drug ivermectin due to the risk of serious adverse events. There is an urgent need to better refine and map high-risk communities. This study aimed to quantify and predict environmental factors associated with loiasis across five bioecological zones in Cameroon. The L. loa microfilaria (mf) prevalence (%) and intensity (mf number/ml) data from 42 villages within an Equatorial Rainforest and Savannah region were examined in relation to climate, topographic and forest-related data derived from satellite remote sensing sources. Differences between zones and regions were examined using nonparametric tests, and the relationship between L. loa mf prevalence, mf intensity, and the environmental factors using polynomial regression models. Overall, the L. loa mf prevalence was 11.6%, L. loa intensity 927.4 mf/ml, mean annual temperature 23.7°C, annual precipitation 2143.2 mm, elevation 790 m, tree canopy cover 46.7%, and canopy height 19.3m. Significant differences between the Equatorial Rainforest and Savannah region were found. Within the Equatorial Rainforest region, no significant differences were found. However, within the Savannah region, significant differences between the three bioecological zones were found, and the regression models indicated that tree canopy cover and elevation were significant predictors, explaining 85.1% of the L. loa mf prevalence (adjusted R2 = 0.851; p<0.001) and tree cover alone was significant, explaining 58.1% of the mf intensity (adjusted R2 = 0.581; p<0.001). The study highlights that environmental analysis can help delineate risk at different geographical scales, which may be practical for developing larger scale operational plans for mapping and implementing safe effective interventions.
Collapse
|
14
|
Kwarteng A, Asiedu E, Sylverken A, Larbi A, Mubarik Y, Apprey C. In silico drug repurposing for filarial infection predicts nilotinib and paritaprevir as potential inhibitors of the Wolbachia 5'-aminolevulinic acid synthase. Sci Rep 2021; 11:8455. [PMID: 33875732 PMCID: PMC8055890 DOI: 10.1038/s41598-021-87976-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 03/31/2021] [Indexed: 11/09/2022] Open
Abstract
Filarial infections affect millions of individuals and are responsible for some notorious disabilities. Current treatment options involve repeated mass drug administrations, which have been met with several challenges despite some successes. Administration of doxycycline, an anti-Wolbachia agent, has shown clinical effectiveness but has several limitations, including long treatment durations and contraindications. We describe the use of an in silico drug repurposing approach to screening a library of over 3200 FDA-approved medications against the filarial endosymbiont, Wolbachia. We target the enzyme which catalyzes the first step of heme biosynthesis in the Wolbachia. This presents an opportunity to inhibit heme synthesis, which leads to depriving the filarial worm of heme, resulting in a subsequent macrofilaricidal effect. High throughput virtual screening, molecular docking and molecular simulations with binding energy calculations led to the identification of paritaprevir and nilotinib as potential anti-Wolbachia agents. Having higher binding affinities to the catalytic pocket than the natural substrate, these drugs have the structural potential to bind and engage active site residues of the wolbachia 5'-Aminolevulinic Acid Synthase. We hereby propose paritaprevir and nilotinib for experimental validations as anti-Wolbachia agents.
Collapse
Affiliation(s)
- Alexander Kwarteng
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana. .,Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana.
| | - Ebenezer Asiedu
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana
| | - Augustina Sylverken
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana
| | - Amma Larbi
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana
| | - Yusif Mubarik
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana
| | - Charles Apprey
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana
| |
Collapse
|
15
|
Hillyer JF. Parasites and Parasitology in this SARS-CoV-2, COVID-19 World: An American Society of Parasitologists Presidential Address. J Parasitol 2021; 106:859-868. [PMID: 33450760 DOI: 10.1645/20-158] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The novel coronavirus disease 2019 (COVID-19) is one of the worst global health crises of this generation. The core of this pandemic is the rapid transmissibility of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, its high morbidity and mortality, and the presence of infectious asymptomatic carriers. As a result, COVID-19 has dominated this year's headlines and commanded significant research attention. As we consider SARS-CoV-2 and the COVID-19 pandemic, it is essential that scientists, governments, the media, and the general population also come to grips with the everyday cost of parasitic diseases. Plasmodium (malaria), schistosomes, filarial worms, hookworms, Ascaris, whipworms, and other protozoan and metazoan parasites take a tremendous toll on local communities. Yet, because most of these diseases are no longer endemic to developed countries, their research and intervention are not funded at levels that are proportional to their global morbidity and mortality. The scientific and public health communities must indeed vigorously fight SARS-CoV-2 and COVID-19, but while doing so and beyond, it will be essential to demonstrate steadfast resolve toward understanding and combating the parasitic diseases that for centuries have haunted humankind.
Collapse
Affiliation(s)
- Julián F Hillyer
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235
| |
Collapse
|
16
|
The Brief Case: Loa loa in a Patient from Nigeria. J Clin Microbiol 2020; 59:59/1/e01587-20. [PMID: 33335076 DOI: 10.1128/jcm.01587-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
17
|
Paulo R, Brito M, Van-Dunem P, Martins A, Novak RJ, Jacob B, Molyneux DM, Unnasch TR, Stothard JR, Kelly-Hope L. Clinical, serological and DNA testing in Bengo Province, Angola further reveals low filarial endemicity and opportunities for disease elimination. Parasite Epidemiol Control 2020; 11:e00183. [PMID: 33072898 PMCID: PMC7548300 DOI: 10.1016/j.parepi.2020.e00183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/31/2020] [Accepted: 09/20/2020] [Indexed: 12/05/2022] Open
Abstract
The prevalence of Loa loa, Onchocerca volvulus and Wuchereria bancrofti infections in an under-surveyed area of Bengo Province, Angola, was determined by surveying 22 communities with a combination of clinical, serological and DNA diagnostics. Additional information was collected on participants' duration of residency, access to mass drug administration, knowledge of insect vectors and use of bednets. A total of 1616 individuals (38.1% male: 61.9% female), with an average age of 43 years, were examined. For L. loa, 6.2% (n = 100/16616) individuals were found to have eyeworm, based on the rapid assessment procedure for loiasis (RAPLOA) surveys, and 11.5% (n =178/1543) based on nested PCR analyses of venous blood. L. loa prevalences in long-term residents (>10 years) and older individuals (>60 years) were significantly higher, and older men with eyeworm were better informed about Chrysops vectors. For O. volvulus, 4.7% (n = 74/1567) individuals were found to be positive by enzyme-linked immunosorbent assay (Ov 16 ELISA), with only three individuals reporting to have ever taken ivermectin. For W. bancrofti, no infections were found using the antigen-based immunochromatographic test (ICT) and real-time PCR analysis; however, 27 individuals presented with lymphatic filariasis (LF) related clinical conditions (lymphoedema = 11, hydrocoele = 14, both = 2). Just under half (45.5%) of the participants owned a bednet, with the majority (71.1%) sleeping under it the night before. Our approach of using combination diagnostics reveals the age-prevalence of loiasis alongside low endemicity of onchocerciasis and LF. Future research foci should be on identifying opportunities for more cost-effective ways to eliminate onchocerciasis and to develop innovative surveillance modalities for clinical LF for individual disease management and disability prevention.
Collapse
Affiliation(s)
- Rossely Paulo
- Centro de Investigacao em Saude de Angola(CISA)/Health Research Centre of Angola, Caxito, Angola
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Miguel Brito
- Centro de Investigacao em Saude de Angola(CISA)/Health Research Centre of Angola, Caxito, Angola
- Health and Technology Research Center (H&TRC), Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Portugal
| | - Pedro Van-Dunem
- National Directorate of Public Health, Ministry of Health, Angola
| | - António Martins
- Centro de Investigacao em Saude de Angola(CISA)/Health Research Centre of Angola, Caxito, Angola
| | - Robert J. Novak
- College of Public Health, University of South Florida, Florida, USA
| | - Benjamin Jacob
- College of Public Health, University of South Florida, Florida, USA
| | - David M. Molyneux
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - J. Russell Stothard
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Louise Kelly-Hope
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| |
Collapse
|
18
|
Boodman C, Marko D, Keynan Y. Slithering Through the Bone Marrow: Loiasis in a Patient With Human T-Cell Leukemia Virus-1-Associated Adult T-Cell Lymphoma. Open Forum Infect Dis 2020; 7:ofaa526. [PMID: 33335934 PMCID: PMC7731528 DOI: 10.1093/ofid/ofaa526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/22/2020] [Indexed: 11/13/2022] Open
Abstract
Loiasis is a filarial disease endemic to areas of Central and West Africa. We present a case of Loa loa microfilaremia in a patient with HTLV-1-related adult T-cell lymphoma. This case may suggest the possible role of cellular immunity in controlling microfilaria burden.
Collapse
Affiliation(s)
- Carl Boodman
- Section of Infectious Diseases, Department of Internal Medicine, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.,Department of Medical Microbiology and Infectious Diseases, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Daniel Marko
- Department of Pathology, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Yoav Keynan
- Section of Infectious Diseases, Department of Internal Medicine, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.,Department of Medical Microbiology and Infectious Diseases, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.,Department of Community Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| |
Collapse
|
19
|
Volpicelli L, De Angelis M, Morano A, Biliotti E, Franchi C, Gabrielli S, Mattiucci S, Di Bonaventura C, Taliani G. Encephalopathy in a patient with loiasis treated with albendazole: A case report. Parasitol Int 2019; 75:102006. [PMID: 31676328 DOI: 10.1016/j.parint.2019.102006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 10/18/2019] [Accepted: 10/25/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Loiasis is a vector-borne parasitic infection endemic across many areas of Central and West Africa. Its treatment is tricky due to the risk of serious neurologic adverse events occurring after the administration of microfilaricidal drugs, like diethylcarbamazine or ivermectin, in subjects with high pre-treatment microfilarial load. Albendazole is currently recommended to slowly reduce microfilaremia before curative regimen is prescribed. CASE PRESENTATION We report the case of a 25-year-old man from Guinea-Conakry who was incidentally diagnosed with highly microfilaremic Loa loa infection. A three weeks regimen of albendazole was prescribed. Minor neurologic side effects occurred after two weeks of administration, while serious encephalopathy developed one week later. Clinical and electroencephalographic features of the patient resembled those of an immune-mediated encephalitis. After exclusion of other causes of encephalopathy, treatment-related Loa loa encephalopathy induced by albendazole was suspected. Corticosteroid treatment was administered and the patient recovered. DISCUSSION Our case confirms that Loa loa treatment-related encephalopathy may occur even during albendazole treatment. The clinical and electroencephalographic similarities between Loa loa albendazole-related encephalopathy and immune-mediated encephalitis suggest the possibility of an underlying inflammation-based pathogenesis. Although corticosteroid administration is not recommended in Loa loa ivermectin-induced encephalopathy, in this case of Loa loa albendazole-induced encephalopathy it may have played a therapeutic role.
Collapse
Affiliation(s)
- Lorenzo Volpicelli
- Hepatology Unit, Department of Translational and Precision Medicine, Sapienza University of Rome, Rome, Italy.
| | - Maurizio De Angelis
- Hepatology Unit, Department of Translational and Precision Medicine, Sapienza University of Rome, Rome, Italy.
| | - Alessandra Morano
- Epilepsy Unit, Department of Human Neurosciences, Sapienza University, Rome, Italy.
| | - Elisa Biliotti
- Hepatology Unit, Department of Translational and Precision Medicine, Sapienza University of Rome, Rome, Italy.
| | - Cristiana Franchi
- Hepatology Unit, Department of Translational and Precision Medicine, Sapienza University of Rome, Rome, Italy.
| | - Simona Gabrielli
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy.
| | - Simonetta Mattiucci
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy.
| | - Carlo Di Bonaventura
- Epilepsy Unit, Department of Human Neurosciences, Sapienza University, Rome, Italy.
| | - Gloria Taliani
- Hepatology Unit, Department of Translational and Precision Medicine, Sapienza University of Rome, Rome, Italy.
| |
Collapse
|
20
|
Buell KG, Whittaker C, Chesnais CB, Jewell PD, Pion SDS, Walker M, Basáñez MG, Boussinesq M. Atypical Clinical Manifestations of Loiasis and Their Relevance for Endemic Populations. Open Forum Infect Dis 2019; 6:ofz417. [PMID: 31696139 PMCID: PMC6824532 DOI: 10.1093/ofid/ofz417] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 10/08/2019] [Indexed: 01/02/2023] Open
Abstract
Background Loiasis is mostly considered a relatively benign infection when compared with other filarial and parasitic diseases, with Calabar swellings and eyeworm being the most common signs. Yet, there are numerous reports in the literature of more serious sequelae. Establishing the relationship between infection and disease is a crucial first step toward estimating the burden of loiasis. Methods We conducted a systematic review of case reports containing 329 individuals and detailing clinical manifestations of loiasis with a focus on nonclassical, atypical presentations. Results Results indicate a high proportion (47%) of atypical presentations in the case reports identified, encompassing a wide range of cardiac, respiratory, gastrointestinal, renal, neurological, ophthalmological, and dermatological pathologies. Individuals with high microfilarial densities and residing in an endemic country were at greater risk of suffering from atypical manifestations. Conclusions Our findings have important implications for understanding the clinical spectrum of conditions associated with Loa loa infection, which extends well beyond the classical eyeworm and Calabar swellings. As case reports may overestimate the true rate of atypical manifestations in endemic populations, large-scale, longitudinal clinico-epidemiological studies will be required to refine our estimates and demonstrate causality between loiasis and the breadth of clinical manifestations reported. Even if the rates of atypical presentations were found to be lower, given that residents of loiasis-endemic areas are both numerous and the group most at risk of severe atypical manifestations, our conclusions support the recognition of loiasis as a significant public health burden across Central Africa.
Collapse
Affiliation(s)
- Kevin G Buell
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research and MRC Centre for Global Infectious Disease Analysis, Faculty of Medicine (St Mary's Campus), Imperial College London, London, UK
| | - Charles Whittaker
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research and MRC Centre for Global Infectious Disease Analysis, Faculty of Medicine (St Mary's Campus), Imperial College London, London, UK
| | - Cédric B Chesnais
- Institut de Recherche pour le Développement (IRD), UMI 233-INSERM U1175-Montpellier University, Montpellier, France
| | - Paul D Jewell
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research and MRC Centre for Global Infectious Disease Analysis, Faculty of Medicine (St Mary's Campus), Imperial College London, London, UK
| | - Sébastien D S Pion
- Institut de Recherche pour le Développement (IRD), UMI 233-INSERM U1175-Montpellier University, Montpellier, France
| | - Martin Walker
- Department of Pathobiology and Population Sciences, London Centre for Neglected Tropical Disease Research, Royal Veterinary College, Hatfield, UK
| | - Maria-Gloria Basáñez
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research and MRC Centre for Global Infectious Disease Analysis, Faculty of Medicine (St Mary's Campus), Imperial College London, London, UK
| | - Michel Boussinesq
- Institut de Recherche pour le Développement (IRD), UMI 233-INSERM U1175-Montpellier University, Montpellier, France
| |
Collapse
|
21
|
Shey RA, Ghogomu SM, Esoh KK, Nebangwa ND, Shintouo CM, Nongley NF, Asa BF, Ngale FN, Vanhamme L, Souopgui J. In-silico design of a multi-epitope vaccine candidate against onchocerciasis and related filarial diseases. Sci Rep 2019; 9:4409. [PMID: 30867498 PMCID: PMC6416346 DOI: 10.1038/s41598-019-40833-x] [Citation(s) in RCA: 199] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/25/2019] [Indexed: 01/02/2023] Open
Abstract
Onchocerciasis is a parasitic disease with high socio-economic burden particularly in sub-Saharan Africa. The elimination plan for this disease has faced numerous challenges. A multi-epitope prophylactic/therapeutic vaccine targeting the infective L3 and microfilaria stages of the parasite's life cycle would be invaluable to achieve the current elimination goal. There are several observations that make the possibility of developing a vaccine against this disease likely. For example, despite being exposed to high transmission rates of infection, 1 to 5% of people have no clinical manifestations of the disease and are thus considered as putatively immune individuals. An immuno-informatics approach was applied to design a filarial multi-epitope subunit vaccine peptide consisting of linear B-cell and T-cell epitopes of proteins reported to be potential novel vaccine candidates. Conservation of the selected proteins and predicted epitopes in other parasitic nematode species suggests that the generated chimera could be helpful for cross-protection. The 3D structure was predicted, refined, and validated using bioinformatics tools. Protein-protein docking of the chimeric vaccine peptide with the TLR4 protein predicted efficient binding. Immune simulation predicted significantly high levels of IgG1, T-helper, T-cytotoxic cells, INF-γ, and IL-2. Overall, the constructed recombinant putative peptide demonstrated antigenicity superior to current vaccine candidates.
Collapse
Affiliation(s)
- Robert Adamu Shey
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium.,Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Stephen Mbigha Ghogomu
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Kevin Kum Esoh
- Department of Biochemistry, Faculty of Science, Jomo Kenyatta University of Agriculture and Technology, Juja, Kenya
| | - Neba Derrick Nebangwa
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Cabirou Mounchili Shintouo
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Nkemngo Francis Nongley
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Bertha Fru Asa
- Department of Public Health and Hygiene, Faculty of Health Science, University of Buea, Buea, Cameroon
| | - Ferdinand Njume Ngale
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium.,Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium.
| |
Collapse
|
22
|
Badia-Rius X, Betts H, Molyneux DH, Kelly-Hope LA. Environmental factors associated with the distribution of Loa loa vectors Chrysops spp. in Central and West Africa: seeing the forest for the trees. Parasit Vectors 2019; 12:72. [PMID: 30728063 PMCID: PMC6366063 DOI: 10.1186/s13071-019-3327-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 01/29/2019] [Indexed: 11/16/2022] Open
Abstract
Background Loiasis is caused by the filarial parasite Loa loa, which is widespread through Central and West Africa and largely confined the tropical equatorial rainforests. The tabanid flies Chrysops silacea and Chrysops dimidiata are the main vectors driving transmission. This study aimed to better define the spatial distribution and ecological niche of the two vectors to help define spatial-temporal risk and target appropriate, timely intervention strategies for filariasis control and elimination programmes. Methods Chrysops spp. distributions were determined by collating information from the published literature into a database, detailing the year, country, locality, latitude/longitude and species collected. Environmental factors including climate, elevation and tree canopy characteristics were summarised for each vector from data obtained from satellite modelled data or imagery, which were also used to identify areas with overt landcover changes. The presence of each Chrysops vector was predicted using a maximum entropy species distribution modelling (MaxEnt) method. Results A total of 313 location-specific data points from 59 published articles were identified across seven loiasis endemic countries. Of these, 186 sites were included in the climate and elevation analysis, and due to overt landcover changes, 83 sites included in tree canopy analysis and MaxEnt model. Overall, C. silacea and C. dimidiata were found to have similar ranges; annual mean temperature (24.6 °C and 24.1 °C, respectively), annual precipitation (1848.6 mm and 1868.8 mm), elevation (368.8 m and 400.6 m), tree canopy cover (61.4% and 66.9%) and tree canopy height (22.4 m and 25.1 m). MaxEnt models found tree canopy coverage was a significant environmental variable for both vectors. Conclusions The Chrysops spp. database and large-scale environmental analysis provides insights into the spatial and ecological parameters of the L. loa vectors driving transmission. These may be used to further delineate loiasis risk, which will be important for implementing filariasis control and elimination programmes in the equatorial rainforest region of Central and West Africa. Electronic supplementary material The online version of this article (10.1186/s13071-019-3327-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Xavier Badia-Rius
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Hannah Betts
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David H Molyneux
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Louise A Kelly-Hope
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
| |
Collapse
|
23
|
Wanji S, Chounna Ndongmo WP, Fombad FF, Kengne-Ouafo JA, Njouendou AJ, Longang Tchounkeu YF, Koudou B, Bockarie M, Fobi G, Roungou JB, Enyong PA. Impact of repeated annual community directed treatment with ivermectin on loiasis parasitological indicators in Cameroon: Implications for onchocerciasis and lymphatic filariasis elimination in areas co-endemic with Loa loa in Africa. PLoS Negl Trop Dis 2018; 12:e0006750. [PMID: 30226900 PMCID: PMC6161907 DOI: 10.1371/journal.pntd.0006750] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 09/28/2018] [Accepted: 08/13/2018] [Indexed: 11/18/2022] Open
Abstract
Background Loiasis is a filarial infection endemic in the rainforest zone of west and central Africa particularly in Cameroon, Gabon, Republic of Congo, and Democratic Republic of the Congo. Repeated treatments with ivermectin have been delivered using the annual community directed treatment with ivermectin (CDTI) approach for several years to control onchocerciasis in some Loa loa-Onchocerca volvulus co-endemic areas. The impact of CDTI on loiasis parasitological indicators is not known. We, therefore, designed this cross sectional study to explore the effects of several rounds of CDTI on parasitological indicators of loiasis. Methodology/Principal findings The study was conducted in the East, Northwest and Southwest 2 CDTI projects of Cameroon. Individuals who consented to participate were interviewed for ivermectin treatment history and enrolled for parasitological screening using thick smears. Ivermectin treatment history was correlated with loiasis prevalence/intensity. A total of 3,684 individuals were recruited from 36 communities of the 3 CDTI projects and 900 individuals from 9 villages in a non-CDTI district. In the East, loiasis prevalence was 29.3% (range = 24.2%–34.6%) in the non-CDTI district but 16.0% (3.3%–26.6%) in the CDTI district with 10 ivermectin rounds (there were no baseline data for the latter). In the Northwest and Southwest 2 districts, reductions from 30.5% to 17.9% (after 9 ivermectin rounds) but from 8.1% to 7.8% (not significantly different after 14 rounds) were registered post CDTI, respectively. Similar trends in infection intensity were observed in all sites. There was a negative relationship between adherence to ivermectin treatment and prevalence/intensity of infection in all sites. None of the children (aged 10–14 years) examined in the East CDTI project harboured high (8,000–30,000 mf/ml) or very high (>30,000 mf/ml) microfilarial loads. Individuals who had taken >5 ivermectin treatments were 2.1 times more likely to present with no microfilaraemia than those with less treatments. Conclusion In areas where onchocerciasis and loiasis are co-endemic, CDTI reduces the number of, and microfilaraemia in L. loa-infected individuals, and this, in turn, will help to prevent non-neurological and neurological complications post-ivermectin treatment among CDTI adherents. Loa loa (the parasite causing loiasis), also known as African eye worm, is endemic in forest areas of west and central Africa. In several of the endemic areas, it co-exists with onchocerciasis and lymphatic filariasis (LF). Because of the benefit individuals suffering from onchocerciasis could have by taking ivermectin where the disease is severe, despite the risk of developing serious side-effects due to being co-infected with L. loa, mass drug administration (MDA) of ivermectin for the control of onchocerciasis has been ongoing in areas where the two diseases overlap. Ivermectin is also effective against loiasis. It is, therefore, hypothesized that several years of ivermectin MDA against onchocerciasis in those areas may have impacted on parasitological indicators for loiasis. In particular, we assess the impact of annual community directed treatment with ivermectin (CDTI) on loiasis with specific reference to the relationship between adherence to treatment and the risk of developing severe (nervous system) complications following ivermectin treatment. We also discuss the feasibility of eliminating onchocerciasis and/or LF in areas endemic for L. loa with ivermectin as the sole intervention tool.
Collapse
Affiliation(s)
- Samuel Wanji
- Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
- * E-mail:
| | - Winston Patrick Chounna Ndongmo
- Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Fanny Fri Fombad
- Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Jonas Arnaud Kengne-Ouafo
- Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Abdel Jelil Njouendou
- Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | | | - Benjamin Koudou
- Centre for Neglected Tropical Diseases (incorporating the Lymphatic Filariasis Support Centre), Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Moses Bockarie
- Centre for Neglected Tropical Diseases (incorporating the Lymphatic Filariasis Support Centre), Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Grace Fobi
- African Program for Onchocerciasis Control (APOC), Ouagadougou, Burkina Faso
| | | | - Peter A. Enyong
- Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| |
Collapse
|
24
|
Kelly-Hope LA, Blundell HJ, Macfarlane CL, Molyneux DH. Innovative Surveillance Strategies to Support the Elimination of Filariasis in Africa. Trends Parasitol 2018; 34:694-711. [PMID: 29958813 DOI: 10.1016/j.pt.2018.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/18/2018] [Accepted: 05/30/2018] [Indexed: 01/18/2023]
Abstract
Lymphatic filariasis (LF) and onchocerciasis are two neglected tropical diseases (NTDs) of public health significance targeted for global elimination. The World Health Organization (WHO) African Region is a priority region, with the highest collective burden of LF and onchocerciasis globally. Coendemic loiasis further complicates elimination due to the risk of adverse events associated with ivermectin treatment. A public health framework focusing on health-related data, systematic collection of data, and analysis and interpretation of data is used to highlight the range of innovative surveillance strategies required for filariasis elimination. The most recent and significant developments include: rapid point-of-care test (POCT) diagnostics; clinical assessment tools; new WHO guidelines; open-access online data portals; mHealth platforms; large-scale prevalence maps; and the optimisation of mathematical models.
Collapse
Affiliation(s)
- Louise A Kelly-Hope
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Harriet J Blundell
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Cara L Macfarlane
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David H Molyneux
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| |
Collapse
|
25
|
Whittaker C, Walker M, Pion SD, Chesnais CB, Boussinesq M, Basáñez MG. The Population Biology and Transmission Dynamics of Loa loa. Trends Parasitol 2018; 34:335-350. [DOI: 10.1016/j.pt.2017.12.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/10/2017] [Accepted: 12/11/2017] [Indexed: 11/27/2022]
|
26
|
The changing global landscape of health and disease: addressing challenges and opportunities for sustaining progress towards control and elimination of neglected tropical diseases (NTDs). Parasitology 2018; 145:1647-1654. [PMID: 29547362 DOI: 10.1017/s0031182018000069] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The drive to control neglected tropical diseases (NTDs) has had many successes but to reach defined targets new approaches are required. Over the last decade, NTD control programmes have benefitted from increased resources, and from effective partnerships and long-term pharmaceutical donations. Although the NTD agenda is broader than those diseases of parasitic aetiology there has been a massive up-scaling of the delivery of medicines to some billion people annually. Recipients are often the poorest, with the aspiration that NTD programmes are key to universal health coverage as reflected within the 2030 United Nations sustainable development goals (SDGs). To reach elimination targets, the community will need to adapt global events and changing policy environments to ensure programmes are responsive and can sustain progress towards NTD targets. Innovative thinking embedded within regional and national health systems is needed. Policy makers, managers and frontline health workers are the mediators between challenge and change at global and local levels. This paper attempts to address the challenges to end the chronic pandemic of NTDs and achieve the SDG targets. It concludes with a conceptual framework that illustrates the interactions between these key challenges and opportunities and emphasizes the health system as a critical mediator.
Collapse
|
27
|
Abstract
A variety of arthropods, protozoa, and helminths infect the skin and subcutaneous tissues and may be identified by anatomic pathologists in standard cytology and histology preparations. The specific organisms seen vary greatly with the patient's exposure history, including travel to or residence in endemic countries. Arthropods are the most commonly encountered parasites in the skin and subcutaneous tissues and include Sarcoptes scabei, Demodex species, Tunga penetrans, and myiasis-causing fly larvae. Protozoal parasites such as Leishmania may also be common in some settings. Helminths are less often seen, and include round worms (eg, Dirofilaria spp.), tapeworms (eg, Taenia solium, Spirometra spp.), and flukes (eg, Schistosoma spp.). This review covers the epidemiologic and histopathologic features of common parasitic infections of the skin and subcutaneous tissues.
Collapse
|
28
|
Gedge LM, Bettis AA, Bradley MH, Hollingsworth TD, Turner HC. Economic evaluations of lymphatic filariasis interventions: a systematic review and research needs. Parasit Vectors 2018; 11:75. [PMID: 29391042 PMCID: PMC5793442 DOI: 10.1186/s13071-018-2616-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 01/02/2018] [Indexed: 01/13/2023] Open
Abstract
In 2000, the World Health Organization established the Global Programme to Eliminate Lymphatic Filariasis (GPELF), with the goal of eliminating the disease as a public health problem by 2020. Since the start of the programme, a cumulative total of 6.2 billion treatments have been delivered to affected populations - with more than 556 million people treated in 2015 alone. In this paper, we perform a rigorous systematic review of the economic evaluations of lymphatic filariasis interventions have been conducted. We demonstrate that the standard interventions to control lymphatic filariasis are consistently found to be highly cost-effective. This finding has important implications for advocacy groups and potential funders. However, there are several important inconsistencies and research gaps that need to be addressed as we move forward towards the 2020 elimination goals. One of the most important identified research gaps was a lack of evaluation of new interventions specifically targeting areas co-endemic with onchocerciasis and Loa loa - which could become a major barrier to achieving elimination.
Collapse
Affiliation(s)
- Lukyn M. Gedge
- School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG UK
| | - Alison A. Bettis
- London Centre for Neglected Tropical Disease Research, London, UK
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG UK
| | | | - T. Déirdre Hollingsworth
- Mathematics Institute, University of Warwick, Coventry, CV4 7AL UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL UK
- Big Data Institute, University of Oxford, Oxford, OX3 7LF UK
| | - Hugo C. Turner
- Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
29
|
Brant TA, Okorie PN, Ogunmola O, Ojeyode NB, Fatunade S, Davies E, Saka Y, Stanton MC, Molyneux DH, Russell Stothard J, Kelly-Hope LA. Integrated risk mapping and landscape characterisation of lymphatic filariasis and loiasis in South West Nigeria. Parasite Epidemiol Control 2018; 3:21-35. [PMID: 29774296 PMCID: PMC5952684 DOI: 10.1016/j.parepi.2017.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/20/2017] [Accepted: 12/26/2017] [Indexed: 11/26/2022] Open
Abstract
Nigeria has the heaviest burden of lymphatic filariasis (LF) in sub-Saharan Africa, which is caused by the parasite Wuchereria bancrofti and transmitted by Anopheles mosquitoes. LF is targeted for elimination and the national programme is scaling up mass drug administration (MDA) across the country to interrupt transmission. However, in some regions the co-endemicity of the filarial parasite Loa loa (loiasis) is an impediment due to the risk of severe adverse events (SAEs) associated with the drug ivermectin. To better understand factors influencing LF elimination in loiasis areas, this study conducted a cross-sectional survey on the prevalence and co-distribution of the two infections, and the potential demographic, landscape, human movement, and intervention-related risk factors at a micro-level in the South West zone of Nigeria. In total, 870 participants from 10 communities on the fringe of a meso-endemic loiasis area of Osun State were selected. LF prevalence was measured by clinical assessment and using the rapid immunochromatographic test (ICT) to detect W. bancrofti antigen. Overall LF prevalence was low with ICT positivity ranging from 0 to 4.7%, with only 1 hydrocoele case identified. Males had significantly higher ICT positivity than females (3.2% vs 0.8%). Participants who did not sleep under a bed net had higher ICT positivity (4.0%) than those who did (1.3%). ICT positivity was also higher in communities with less tree coverage/canopy height (2.5-2.8%) than more forested areas with greater tree coverage/canopy height (0.9-1.0%). In comparison, loiasis was determined using the rapid assessment procedure for loiasis (RAPLOA), and found in all 10 communities with prevalence ranging from 1.4% to 11.2%. No significant difference was found by participants' age or sex. However, communities with predominately shrub land (10.4%) or forested land cover (6.2%) had higher prevalence than those with mosaic vegetation/croplands (2.5%). Satellite imagery showed denser forested areas in higher loiasis prevalence communities, and where low or no ICT positivity was found. Only one individual was found to be co-infected. GPS tracking of loiasis positive cases and controls also highlighted denser forested areas within higher loiasis risk communities and the sparser land cover in lower-risk communities. Mapping LF-loiasis distributions against landscape characteristics helped to highlight the micro-heterogeneity, identify potential SAE hotspots, and determine the safest and most appropriate treatment strategy.
Collapse
Affiliation(s)
- Tara A. Brant
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Patricia N. Okorie
- Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Olushola Ogunmola
- Federal Ministry of Health, Department of Public Health, Neglected Tropical Diseases Division, South West Zone, Nigeria
| | - Nureni Bolaji Ojeyode
- State Ministry of Health, Department of Primary Health Care and Disease Control, Division of Neglected Tropical Diseases, Osogbo, Osun State, Nigeria
| | - S.B. Fatunade
- State Ministry of Health, Department of Primary Health Care and Disease Control, Division of Neglected Tropical Diseases, Osogbo, Osun State, Nigeria
| | - Emmanuel Davies
- Federal Ministry of Health, Department of Public Health, Neglected Tropical Diseases Division, Abuja, Nigeria
| | - Yisa Saka
- Federal Ministry of Health, Department of Public Health, Neglected Tropical Diseases Division, Abuja, Nigeria
| | - Michelle C. Stanton
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David H. Molyneux
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - J. Russell Stothard
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Louise A. Kelly-Hope
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| |
Collapse
|
30
|
Brito M, Paulo R, Van-Dunem P, Martins A, Unnasch TR, Novak RJ, Jacob B, Stanton MC, Molyneux DH, Kelly-Hope LA. Rapid integrated clinical survey to determine prevalence and co-distribution patterns of lymphatic filariasis and onchocerciasis in a Loa loa co-endemic area: The Angolan experience. Parasite Epidemiol Control 2017; 2:71-84. [PMID: 29774284 PMCID: PMC5952692 DOI: 10.1016/j.parepi.2017.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/04/2017] [Accepted: 05/06/2017] [Indexed: 01/03/2023] Open
Abstract
The Republic of Angola is a priority country for onchocerciasis and lymphatic filariasis (LF) elimination, however, the co-distribution of the filarial parasite Loa loa (loiasis) is a significant impediment, due to the risk of severe adverse events (SAEs) associated with ivermectin used in mass drug administration (MDA) campaigns. Angola has a high risk loiasis zone identified in Bengo Province where alternative interventions may need to be implemented; however, the presence and geographical overlap of the three filarial infections/diseases are not well defined. Therefore, this study conducted a rapid integrated filarial mapping survey based on readily identifiable clinical conditions of each disease in this risk zone to help determine prevalence and co-distribution patterns in a timely manner with limited resources. In total, 2007 individuals from 29 communities in five provincial municipalities were surveyed. Community prevalence estimates were determined by the rapid assessment procedure for loiasis (RAPLOA) and rapid epidemiological mapping of onchocerciasis (REMO) together with two questions on LF clinical manifestations (presence of lymphoedema, hydrocoele). Overall low levels of endemicity, with different overlapping distributions were found. Loiasis was found in 18 communities with a prevalence of 2.0% (31/1571), which contrasted to previous results defining the area as a high risk zone. Onchocerciasis prevalence was 5.3% (49/922) in eight communities, and LF prevalence was 0.4% for lymphoedema (8/2007) and 2.6% for hydrocoeles (20/761 males) in seven and 12 communities respectively. The clinical mapping survey method helped to highlight that all three filarial infections are present in this zone of Bengo Province. However, the significant difference in loiasis prevalence found between the past and this current survey suggests that further studies including serological and parasitological confirmation are required. This will help determine levels of infection and risk, understand the associations between clinical, serological and parasitological prevalence patterns, and better determine the most appropriate treatment strategies to reach onchocerciasis and LF elimination targets in the loiasis co-endemic areas. Our results also suggest that the utility of the earlier RAPLOA derived maps, based on surveys undertaken over a decade ago, are likely to be invalid given the extent of population movement and environmental change, particularly deforestation, and that fine scale micro-mapping is required to more precisely delineate the interventions required defined by these complex co-endemicities.
Collapse
Affiliation(s)
- Miguel Brito
- Centro de Investigacao em Saude de Angola/Health Research Centre of Angola, Caxito, Angola
- Lisbon School of Health Technology, Lisbon, Portugal
| | - Rossely Paulo
- Centro de Investigacao em Saude de Angola/Health Research Centre of Angola, Caxito, Angola
- Centre for Neglected Tropical Diseases, and Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Pedro Van-Dunem
- National Directorate of Public Health, Ministry of Health, Angola
| | - António Martins
- Centro de Investigacao em Saude de Angola/Health Research Centre of Angola, Caxito, Angola
| | - Thomas R Unnasch
- College of Public Health, Department of Global Health, University of South Florida, Florida, USA
| | - Robert J Novak
- College of Public Health, Department of Global Health, University of South Florida, Florida, USA
| | - Benjamin Jacob
- College of Public Health, Department of Global Health, University of South Florida, Florida, USA
| | - Michelle C Stanton
- Centre for Neglected Tropical Diseases, and Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David H Molyneux
- Centre for Neglected Tropical Diseases, and Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Louise A Kelly-Hope
- Centre for Neglected Tropical Diseases, and Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| |
Collapse
|