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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.
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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
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Burger G, Adamou R, Kreuzmair R, Ndoumba WN, Mbassi DE, Mouima AMN, Tabopda CM, Adegnika RM, More A, Okwu DG, Mbadinga LBD, Calle CL, Veletzky L, Metzger WG, Mordmüller B, Ramharter M, Mombo-Ngoma G, Adegnika AA, Zoleko-Manego R, McCall MBB. Eosinophils, basophils and myeloid-derived suppressor cells in chronic Loa loa infection and its treatment in an endemic setting. PLoS Negl Trop Dis 2024; 18:e0012203. [PMID: 38771861 PMCID: PMC11147522 DOI: 10.1371/journal.pntd.0012203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 06/03/2024] [Accepted: 05/08/2024] [Indexed: 05/23/2024] Open
Abstract
BACKGROUND Chronic infection by Loa loa remains an unsolved immunological paradox. Despite harboring subcutaneously migrating adult worms and often high densities of microfilariae, most patients experience only relatively mild symptoms, yet microfilaricidal treatment can trigger life-threatening inflammation. Here, we investigated innate cell populations hypothesized to play a role in these two faces of the disease, in an endemic population in Gabon. METHODOLOGY/PRINCIPAL FINDINGS We analyzed numbers and activation of eosinophils and basophils, as well as myeloid-derived suppressor cell (MDSC) subsets and associated circulating cytokine levels by flow cytometry in sex- and age-matched L. loa-uninfected (LL-), -amicrofilaraemic (MF-) and -microfilaraemic (MF+) individuals (n = 42), as well as microfilaraemic individuals treated with albendazole (n = 26). The percentage of eosinophils was lower in LL- (3.0%) than in the combined L. loa-infected population, but was similar in MF+ (13.1%) and MF- (12.3%). Upon treatment of MF+, eosinophilia increased from day 0 (17.2%) to day 14 (24.8%) and had decreased below baseline at day 168 (6.3%). Expression of the eosinophil activation marker CD123 followed the same pattern as the percentage of eosinophils, while the inverse was observed for CD193 and to some extent CD125. Circulating IL-5 levels after treatment followed the same pattern as eosinophil dynamics. Basophil numbers did not differ between infection states but increased after treatment of MF+. We did not observe differences in MDSC numbers between infection states or upon treatment. CONCLUSIONS/SIGNIFICANCE We demonstrate that both chronic infection and treatment of L. loa microfilaraemia are associated with eosinophil circulation and distinct phenotypical activation markers that might contribute to inflammatory pathways in this setting. In this first ever investigation into MDSC in L. loa infection, we found no evidence for their increased presence in chronic loiasis, suggesting that immunomodulation by L. loa is induced through other pathways.
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Affiliation(s)
- Gerrit Burger
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Rafiou Adamou
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Ruth Kreuzmair
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Wilfrid Ndzebe Ndoumba
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research, Partner sites Hamburg-Borstel-Lübeck-Riems, Germany
| | - Dorothea Ekoka Mbassi
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- German Center for Infection Research, Partner sites Hamburg-Borstel-Lübeck-Riems, Germany
- Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | | | - Ayong More
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Dearie Glory Okwu
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research, Partner sites Hamburg-Borstel-Lübeck-Riems, Germany
| | | | | | - Luzia Veletzky
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | | | - Benjamin Mordmüller
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- German Center for Infection Research, Partner sites Hamburg-Borstel-Lübeck-Riems, Germany
- Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research, Partner sites Hamburg-Borstel-Lübeck-Riems, Germany
| | - Ayola Akim Adegnika
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research, Partner site Tübingen, Tübingen Germany
| | - Rella Zoleko-Manego
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- German Center for Infection Research, Partner sites Hamburg-Borstel-Lübeck-Riems, Germany
- Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Matthew B. B. McCall
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
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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.
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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
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Portela CS, Mendes de Araújo CP, Moura Sousa P, Gomes Simão CL, Silva de Oliveira JC, Crainey JL. Filarial disease in the Brazilian Amazon and emerging opportunities for treatment and control. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2023; 5:100168. [PMID: 38283060 PMCID: PMC10821485 DOI: 10.1016/j.crpvbd.2023.100168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/06/2023] [Accepted: 12/15/2023] [Indexed: 01/30/2024]
Abstract
Following the successful eradication of Wuchereria bancrofti, there are now just three species of conventional microfilaremic human filarial parasites endemic to the Brazilian Amazon region: Mansonella ozzardi, Mansonella perstans and Onchocerca volvulus. The zoonotic filarial parasite Dirofilaria immitis is also found in the Amazon region as are several sylvatic filarial parasites, some of which have been recorded causing zoonoses and some of which have never been recorded outside the region. Onchocerca volvulus is only found in the Amazonia onchocerciasis focus in the Brazilian state of Roraima where it affects the people of the Yanomami tribe living around the densely forested Venezuela border region. Mansonella ozzardi is by far the most common filarial parasite in Brazil and has a broad but patchy distribution throughout the western Amazon region. Recorded in the Brazilian states of Acre, Roraima, Matto Grosso, and within almost every municipality of Amazonas state, it is believed that pollution of the urban stream and river systems prevents the development of the simuliid vectors of M. ozzardi and explains the parasite's reduced distribution within urban areas and an absence of recent reports from the state capital Manaus. Decades of WHO-led periodic ivermectin treatment of Yanomami tribe's people have resulted in the partial suppression of O. volvulus transmission in this focus and has also probably affected the transmission of M. ozzardi in the region. Mansonella perstans, O. volvulus and very probably M. ozzardi infections can all be treated and most likely cured with a 4-6-week treatment course of doxycycline. The Brazilian Ministry of Health does not, however, presently recommend any treatment for mansonellosis infections and thus parasitic infections outside the Amazonia focus are typically left untreated. While the long treatment courses required for doxycycline-based mansonellosis therapies preclude their use in control programmes, new fast-acting filarial drug treatments are likely to soon become available for the treatment of both onchocerciasis and mansonellosis in the Amazon region. Filarial disease management in the Brazilian Amazon is thus likely to become dramatically more viable at a time when the public health importance of these diseases is increasingly being recognized.
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Affiliation(s)
- Cleudecir Siqueira Portela
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Biologia da Interação Patógeno Hospedeiro, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Cláudia Patrícia Mendes de Araújo
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Biologia da Interação Patógeno Hospedeiro, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Patrícia Moura Sousa
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Biologia da Interação Patógeno Hospedeiro, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Carla Letícia Gomes Simão
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Mestrado em Condições de Vida e Situações de Saúde na Amazônia, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - João Carlos Silva de Oliveira
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Saúde Pública na Amazônia, Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Manaus, Amazonas, Brazil
| | - James Lee Crainey
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
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Ekoka Mbassi D, Mombo-Ngoma G, Held J, Okwu DG, Ndzebe-Ndoumba W, Kalkman LC, Ekoka Mbassi FA, Pessanha de Carvalho L, Inoue J, Akinosho MA, Dimessa Mbadinga LB, Yovo EK, Mordmüller B, Kremsner PG, Adegnika AA, Ramharter M, Zoleko-Manego R. Efficacy and safety of ivermectin for the treatment of Plasmodium falciparum infections in asymptomatic male and female Gabonese adults - a pilot randomized, double-blind, placebo-controlled single-centre phase Ib/IIa clinical trial. EBioMedicine 2023; 97:104814. [PMID: 37839134 PMCID: PMC10582777 DOI: 10.1016/j.ebiom.2023.104814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 08/21/2023] [Accepted: 09/15/2023] [Indexed: 10/17/2023] Open
Abstract
BACKGROUND Ivermectin's mosquitocidal effect and in vitro activity against Plasmodium falciparum asexual stages are known. Its in vivo blood-schizonticidal efficacy is unknown. Ivermectin's tolerability and efficacy against P. falciparum infections in Gabonese adults were assessed. METHODS The study consisted of a multiple dose stage and a randomized, double-blind, placebo-controlled stage. Adults with asymptomatic P. falciparum parasitaemia (200-5000 parasites/μl) were enrolled. First, three groups of five participants received 200 μg/kg ivermectin once daily for one, two, and three days, respectively, and then 34 participants were randomized to 300 μg/kg ivermectin or placebo once daily for 3 days. Primary efficacy outcome was time to 90% parasite reduction. Primary safety outcomes were drug-related serious and severe adverse events (Trial registration: PACTR201908520097051). FINDINGS Between June 2019 and October 2020, 49 participants were enrolled. Out of the 34 randomized participants, 29 (85%) completed the trial as per protocol. No severe or serious adverse events were observed. The median time to 90% parasite reduction was 24.1 vs. 32.0 h in the ivermectin and placebo groups, respectively (HR 1.38 [95% CI 0.64 to 2.97]). INTERPRETATION Ivermectin was well tolerated in doses up to 300 μg/kg once daily for three days and asymptomatic P. falciparum asexual parasitaemia was reduced similarly with this dose of ivermectin compared to placebo. Further studies are needed to evaluate plasmodicidal effect of ivermectin at higher doses and in larger samples. FUNDING This study was funded by the Centre de Recherches Médicales de Lambaréné and the Centre for Tropical Medicine of the Bernhard Nocht Institute for Tropical Medicine.
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Affiliation(s)
- Dorothea Ekoka Mbassi
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lübeck-Riems, Germany
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lübeck-Riems, Germany; Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jana Held
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Dearie Glory Okwu
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Wilfrid Ndzebe-Ndoumba
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Franck Aurelien Ekoka Mbassi
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lübeck-Riems, Germany
| | | | - Juliana Inoue
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | | | | | | | - Benjamin Mordmüller
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Peter Gottfried Kremsner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Ayôla Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany; Department of Parasitology, Leiden University Medical Centre (LUMC), 2333 ZA, Leiden, the Netherlands; Fondation pour la Recherche Scientifique, 72 BP45, Cotonou, Benin
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lübeck-Riems, Germany
| | - Rella Zoleko-Manego
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon; Centre for Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lübeck-Riems, Germany; Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.
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Ferreira MU, Crainey JL, Gobbi FG. The search for better treatment strategies for mansonellosis: an expert perspective. Expert Opin Pharmacother 2023; 24:1685-1692. [PMID: 37477269 DOI: 10.1080/14656566.2023.2240235] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/20/2023] [Indexed: 07/22/2023]
Abstract
INTRODUCTION Four species of the Mansonella genus infect millions of people across sub-Saharan Africa and Central and South America. Most infections are asymptomatic, but mansonellosis can be associated with nonspecific clinical manifestations such as fever, headache, arthralgia, and ocular lesions (M. ozzardi); pruritus, arthralgia, abdominal pain, angioedema, skin rash, and fatigue (M. perstans and perhaps Mansonella sp. 'DEUX'); and pruritic dermatitis and chronic lymphadenitis (M. perstans). AREAS COVERED We searched the PubMed and SciELO databases for publications on mansonelliasis in English, Spanish, Portuguese, or French that appeared until 1 May 2023. Literature data show that anthelmintics - single-dose ivermectin for M. ozzardi, repeated doses of mebendazole alone or in combination with diethylcarbamazine (DEC) for M. perstans, and DEC alone for M. streptocerca - are effective against microfilariae. Antibiotics that target Wolbachia endosymbionts, such as doxycycline, are likely to kill adult worms of most, if not all, Mansonella species, but the currently recommended 6-week regimen is relatively impractical. New anthelmintics and shorter antibiotic regimens (e.g. with rifampin) have shown promise in experimental filarial infections and may proceed to clinical trials. EXPERT OPINION We recommend that human infections with Mansonella species be treated, regardless of any apparent clinical manifestations. We argue that mansonellosis, despite being widely considered a benign infection, may represent a direct or indirect cause of significant morbidity that remains poorly characterized at present.
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Affiliation(s)
- Marcelo U Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, NOVA University of Lisbon, Lisbon, Portugal
| | - James Lee Crainey
- Laboratory of Ecology and Transmissible Diseases in the Amazon, Leônidas and Maria Deane Institute, Fiocruz, Manaus, Brazil
| | - Federico G Gobbi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
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7
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Zoleko-Manego R, Kreuzmair R, Veletzky L, Ndzebe-Ndoumba W, Ekoka Mbassi D, Okwu DG, Dimessa-Mbadinga-Weyat LB, Houtsa-Temgoua RD, Mischlinger J, McCall MBB, Kresmner PG, Agnandji ST, Lell B, Adegnika AA, Mombo-Ngoma G, Ramharter M. Efficacy, safety, and tolerability of albendazole and ivermectin based regimens for the treatment of microfilaraemic loiasis in adult patients in Gabon: A randomized controlled assessor blinded clinical trial. PLoS Negl Trop Dis 2023; 17:e0011584. [PMID: 37639396 PMCID: PMC10491396 DOI: 10.1371/journal.pntd.0011584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 09/08/2023] [Accepted: 08/11/2023] [Indexed: 08/31/2023] Open
Abstract
BACKGROUND There is a lack of systematic evidence for strategies to control loiasis transmission in highly endemic regions. Here we assessed albendazole and ivermectin based treatment regimens to reduce Loa loa microfilaraemia in Gabon. METHODS Eligible adult patients with L. loa microfilaraemia between 5,000 and 50,000 microfilariae/ml were randomized to either a control or one of three intervention groups (1:2:2:2 allocation ratio) consisting of three-week twice daily 400mg oral albendazole followed by 1) no treatment, 2) two further weeks of twice daily 400mg albendazole, or 3) a single dose of ivermectin in this open label randomized assessor blinded controlled clinical trial. The primary outcome was the proportion of participants with L. loa microfilaraemia ≤ 100 mf/ml at Day 168. RESULTS In the efficacy-population of 42 patients 0 (0%; control group), 1 (9%; 3-week albendazole), 5 (39%; 5-weeks albendazole) and 2 (22%; 3-week albendazole plus single dose ivermectin) participants met the primary outcome of microfilaraemia below 100/ml at day 168. A 80-90% reduction of microfilaraemia was observed in the active treatment groups. CONCLUSION The 5-week regimen of albendazole or a 3-week regimen of albendazole followed by ivermectin were most efficacious to reduce microfilaraemia. All therapeutic regimens were well tolerated and safe. TRIAL REGISTRATION Trial registered at the Pan-African Clinical Trials Registry: PACTR201807197019027.
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Affiliation(s)
- Rella Zoleko-Manego
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research–Partner Sites Hamburg-Lübeck-Borstel-Riems, Germany
| | - Ruth Kreuzmair
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Radboud University Medical Center, Nijmegen, Netherlands
| | - Luzia Veletzky
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research–Partner Sites Hamburg-Lübeck-Borstel-Riems, Germany
| | | | - Dorothea Ekoka Mbassi
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research–Partner Sites Hamburg-Lübeck-Borstel-Riems, Germany
| | - Dearie G. Okwu
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | | | | | - Johannes Mischlinger
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research–Partner Sites Hamburg-Lübeck-Borstel-Riems, Germany
| | | | - Peter G. Kresmner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research–Partner Site Tübingen, Germany
| | - Selidji T. Agnandji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Betrand Lell
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Division of Infectious Diseases and Tropical Medicine, Department of Medicine 1, Medical University of Vienna, Vienna, Austria
| | - Ayôla A. Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research–Partner Site Tübingen, Germany
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research–Partner Sites Hamburg-Lübeck-Borstel-Riems, Germany
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8
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Eyang-Assengone ER, Makouloutou-Nzassi P, Mbou-Boutambe C, Bangueboussa F, Atsame J, Boundenga L. Status of Onchocerciasis Elimination in Gabon and Challenges: A Systematic Review. Microorganisms 2023; 11:1946. [PMID: 37630506 PMCID: PMC10458829 DOI: 10.3390/microorganisms11081946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/19/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
Control and treatment programs (CDTI) have been set up nationally in all endemic countries to overcome the impact of onchocerciasis on the affected populations. However, Gabon must still succeed in setting up real onchocerciasis control programs. Here, various database articles have been used to provide the scientific community with a summary document showing the mapping of this disease in Gabon. The articles dealing with onchocerciasis, animal reservoirs, surveillance, and elimination were analyzed. Results showed that little research has been performed. Most studies are concentrated in one region (The area of Lastourville). In addition, we observed that the distribution of the disease varies significantly across the country. Indeed, specific environments present a hyper-endemicity of the disease, while others are meso and hypo-endemic. So, we found some departments with a prevalence ranging from 0% to over 20%; within them, villages had infection levels comprising 10% to 60%, indicating potential hotspots. Vectors activities were studied in some areas. This paper showed the challenges encountered in the country to eliminate this disease. One solution is a deeper understanding of the disease's bioecology to establish effective health policies to eliminate onchocerciasis in Gabon effectively.
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Affiliation(s)
- Elsa-Rush Eyang-Assengone
- Unité de Recherche en Ecologie de la Santé (URES), Centre Interdisciplinaire de Recherches Médicales de Franceville (CIRMF), Franceville BP 769, Gabon; (P.M.-N.); (C.M.-B.); (F.B.)
| | - Patrice Makouloutou-Nzassi
- Unité de Recherche en Ecologie de la Santé (URES), Centre Interdisciplinaire de Recherches Médicales de Franceville (CIRMF), Franceville BP 769, Gabon; (P.M.-N.); (C.M.-B.); (F.B.)
- Département de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale (IRET/CENAREST), Libreville BP 13354, Gabon
| | - Clark Mbou-Boutambe
- Unité de Recherche en Ecologie de la Santé (URES), Centre Interdisciplinaire de Recherches Médicales de Franceville (CIRMF), Franceville BP 769, Gabon; (P.M.-N.); (C.M.-B.); (F.B.)
| | - Félicien Bangueboussa
- Unité de Recherche en Ecologie de la Santé (URES), Centre Interdisciplinaire de Recherches Médicales de Franceville (CIRMF), Franceville BP 769, Gabon; (P.M.-N.); (C.M.-B.); (F.B.)
| | - Julienne Atsame
- Programme de Lutte Contre les Maladies Parasitaires, Ministère de la Santé du Gabon, Libreville BP 2434, Gabon;
| | - Larson Boundenga
- Unité de Recherche en Ecologie de la Santé (URES), Centre Interdisciplinaire de Recherches Médicales de Franceville (CIRMF), Franceville BP 769, Gabon; (P.M.-N.); (C.M.-B.); (F.B.)
- Département d’anthropologie, Université de Durham, South Road, Durham DH1 3LE, UK
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Jimenez-Vila G, Campillo-Grau A, Espiau M, Soriano-Arandes A, Soler-Palacin P, Sulleiro E, Zarzuela F. Loiasis: An Unusual Cause of Eosinophilia in a Pediatric Patient. Pediatr Infect Dis J 2023; 42:e132. [PMID: 36728668 DOI: 10.1097/inf.0000000000003820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Guillem Jimenez-Vila
- Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital UniversitariVall d'Hebron, Barcelona, Spain
| | - Anna Campillo-Grau
- Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital UniversitariVall d'Hebron, Barcelona, Spain
| | - María Espiau
- Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital UniversitariVall d'Hebron, Barcelona, Spain
| | - Antoni Soriano-Arandes
- Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital UniversitariVall d'Hebron, Barcelona, Spain
| | - Pere Soler-Palacin
- Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital UniversitariVall d'Hebron, Barcelona, Spain
| | - Elena Sulleiro
- Microbiology Department, Hospital Universitari Vall d'Hebron, Barcelona, Spain
| | - Francesc Zarzuela
- Microbiology Department, Hospital Universitari Vall d'Hebron, Barcelona, Spain
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10
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Subbarao S, Thompson R, Klion A, Hauck FR, Thomas TA. Cases of Loiasis Among a Congolese Family: Screening for Loiasis Among Newly Arrived Refugees From Endemic Areas. J Nurse Pract 2023; 19:104505. [PMID: 36936748 PMCID: PMC10019557 DOI: 10.1016/j.nurpra.2022.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Loiasis is a parasitic infection caused by the filarial nematode Loa loa within endemic regions of West and Central Africa. These regions include areas co-endemic for other nematode infections. Although loiasis is rarely seen in the United States (US), primary care providers who regularly see refugees from endemic areas should be aware of its clinical presentation, diagnostic work-up, and initial management. Given the challenges of diagnosing loiasis, especially in low prevalence settings, we present cases of four family members, two of whom were diagnosed with loiasis, and discuss an approach to screening populations from endemic regions during their initial Refugee Health Examination upon arrival to the US.
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Affiliation(s)
- Shalini Subbarao
- School of Medicine, University of Virginia, Charlottesville, VA, USA
| | - Reagan Thompson
- School of Nursing, University of Virginia, Charlottesville, VA, USA
- Department of Population Health, University of Virginia, Charlottesville, VA, USA
| | - Amy Klion
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Fern R Hauck
- Department of Family Medicine, University of Virginia, Charlottesville, VA, USA
| | - Tania A Thomas
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, USA
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11
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Davi SD, Ramharter M, Nordmann T. Loiasis – Eine extrem vernachlässigte Tropenerkrankung. FLUGMEDIZIN · TROPENMEDIZIN · REISEMEDIZIN - FTR 2023. [DOI: 10.1055/a-1999-1821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
ZUSAMMENFASSUNGRund 10–15 Mio. Menschen in Zentral- und Westafrika sind mit der Filarie Loa loa infiziert. Obwohl die assoziierte Krankheitslast vergleichbar mit wichtigen Tropenkrankheiten wie der Schistosomiasis ist, gilt die Loaisis bisher als extrem vernachlässigte Tropenerkrankung. Parasitologisch wird differenziert zwischen der mikrofilariämen Loiasis, bei der die Mikrofilarien mittels Mikroskopie im Blutausstrich nachgewiesen werden, und der okkulten Loiasis, die nur bei entsprechender Exposition durch typische Symptome diagnostiziert werden kann. Pathognomonische Symptome sind die Wanderung des adulten Wurms in der Konjunktiva („afrikanischer Augenwurm“) sowie die transiente Calabar-Schwellung. Die Therapie der Loaisis stellt vor allem in Endemiegebieten oft eine große Herausforderung dar. Potenziell schwere Nebenwirkungen der verfügbaren Medikamente sowie das hohe Risiko einer Reinfektion führen meist dazu, dass L. loa-Patient*innen in den Endemiegebieten keine Therapie erhalten.
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Affiliation(s)
- Saskia Dede Davi
- Bernhard-Nocht-Institut für Tropenmedizin, Abteilung Klinische Forschung, Hamburg
| | - Michael Ramharter
- Bernhard-Nocht-Institut für Tropenmedizin, Abteilung Klinische Forschung, Hamburg
- Sektion Klinische Tropenmedizin, I. Medizinische Klinik des Universitätsklinikums Hamburg-Eppendorf
| | - Tamara Nordmann
- Bernhard-Nocht-Institut für Tropenmedizin, Abteilung Klinische Forschung, Hamburg
- Sektion Klinische Tropenmedizin, I. Medizinische Klinik des Universitätsklinikums Hamburg-Eppendorf
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12
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Tamarozzi F, Rodari P, Salas-Coronas J, Bottieau E, Salvador F, Soriano-Pérez MJ, Cabeza-Barrera MI, Van Esbroeck M, Treviño B, Buonfrate D, Gobbi FG. A large case series of travel-related Mansonella perstans (vector-borne filarial nematode): a TropNet study in Europe. J Travel Med 2022; 29:6567953. [PMID: 35417002 PMCID: PMC9635058 DOI: 10.1093/jtm/taac048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/25/2022] [Accepted: 04/01/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Infection with Mansonella perstans is a neglected filariasis, widely distributed in sub-Saharan Africa, characterized by an elusive clinical picture; treatment for mansonellosis is not standardized. This retrospective study aimed to describe the clinical features, treatment schemes and evolution, of a large cohort of imported cases of M. perstans infection seen in four European centres for tropical diseases. METHODS Mansonella perstans infections, diagnosed by identification of blood microfilariae in migrants, expatriates and travellers, collected between 1994 and 2018, were retrospectively analysed. Data concerning demographics, clinical history and laboratory examinations at diagnosis and at follow-up time points were retrieved. RESULTS A total of 392 patients were included in the study. Of the 281 patients for whom information on symptoms could be retrieved, 150 (53.4%) reported symptoms, abdominal pain and itching being the most frequent. Positive serology and eosinophilia were present in 84.4% and 66.1%, respectively, of those patients for whom these data were available. Concomitant parasitic infections were reported in 23.5% of patients. Treatment, administered to 325 patients (82.9%), was extremely heterogeneous between and within centres; the most commonly used regimen was mebendazole 100 mg twice a day for 1 month. A total of 256 (65.3%) patients attended a first follow-up, median 3 months (interquartile range 2-12) after the first visit; 83.1% of patients having received treatment based on mebendazole and/or doxycycline, targeting Wolbachia, became amicrofilaremic, 41.1-78.4% of whom within 12 months from single treatment. CONCLUSIONS Lack of specific symptoms, together with the inconstant positivity of parasitological and antibody-based assays in the infected population, makes the clinical suspicion and screening for mansonellosis particularly difficult. Prospective studies evaluating prevalence of infection in migrants from endemic areas, infection-specific morbidity, presence of Wolbachia endosymbionts in M. perstans populations from different geographical areas and efficacy of treatment regimens are absolutely needed to optimize the clinical management of infection.
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Affiliation(s)
- Francesca Tamarozzi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| | - Paola Rodari
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| | | | - Emmanuel Bottieau
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Fernando Salvador
- Tropical Medicine Unit Vall d'Hebron-Drassanes, Infectious Diseases Department, Vall d'Hebron University Hospital, PROSICS Barcelona, Barcelona, Spain
| | | | | | - Marjan Van Esbroeck
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Begoña Treviño
- Tropical Medicine Unit Vall d'Hebron-Drassanes, Infectious Diseases Department, Vall d'Hebron University Hospital, PROSICS Barcelona, Barcelona, Spain
| | - Dora Buonfrate
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
| | - Federico G Gobbi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar di Valpolicella, Verona, Italy
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13
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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.
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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
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14
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Ekoka Mbassi FA, Mombo-Ngoma G, Ndoumba WN, Yovo EK, Eberhardt KA, Ekoka Mbassi D, Adegnika AA, Agnandji ST, Bouyou-Akotet MK, Ramharter M, Zoleko-Manego R. Performance of Field's Stain Compared with Conventional Giemsa Stain for the Rapid Detection of Blood Microfilariae in Gabon. Am J Trop Med Hyg 2022; 107:383-387. [PMID: 35895407 PMCID: PMC9393457 DOI: 10.4269/ajtmh.22-0061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 03/25/2021] [Indexed: 11/15/2022] Open
Abstract
Filarial infections caused by Loa loa and Mansonella perstans are a considerable public health burden in rural regions of Central Africa. Rapid diagnostic tools for the detection of microfilariae in the blood are needed. Field's stain is a rapid staining technique for microscopic slides originally established for malaria diagnostics. It requires less than 1 minute of staining compared with conventional staining protocols requiring at least 15 to 20 minutes for staining and could thus significantly accelerate diagnostics for human filariasis. Here we evaluated Field's stain as a rapid staining technique in comparison to Giemsa stain for the detection of microfilariae in peripheral blood. Blood smears were collected from 175 participants residing in the region of Lambaréné and Fougamou, Gabon. Each participant's samples were stained in parallel with Field's stain and conventional Giemsa stain. Slides were then microscopically assessed and compared for qualitative and quantitative results by a blinded assessor for the two endemic filarial blood pathogens M. perstans and L. loa. Field's stain shows excellent diagnostic performance characteristics for L. loa microfilariae compared with Giemsa staining. Concordance was favorable for M. perstans although lower than for L. loa. Field's stain offers a rapid alternative to Giemsa stain for detection of L. loa microfilariae in thick blood smears. This could help accelerate diagnostics of blood filarial pathogens in mass screening programs or resource constrained health care institutions with high patient load.
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Affiliation(s)
- Franck-A. Ekoka Mbassi
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical‚ Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, Libreville, Gabon
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical‚ Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | - Kirsten A. Eberhardt
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical‚ Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Sites Hamburg-Lübeck-Borstel-Riems
| | - Dorothea Ekoka Mbassi
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical‚ Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Sites Hamburg-Lübeck-Borstel-Riems
| | - Ayôla A. Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | | | - Marielle K. Bouyou-Akotet
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, Libreville, Gabon
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical‚ Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Sites Hamburg-Lübeck-Borstel-Riems
| | - Rella Zoleko-Manego
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical‚ Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Sites Hamburg-Lübeck-Borstel-Riems
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Dieki R, Nsi-Emvo E, Akue JP. The Human Filaria Loa loa: Update on Diagnostics and Immune Response. Res Rep Trop Med 2022; 13:41-54. [PMID: 35936385 PMCID: PMC9355020 DOI: 10.2147/rrtm.s355104] [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: 02/10/2022] [Accepted: 06/03/2022] [Indexed: 11/24/2022] Open
Abstract
Loa loa loiasis was considered an anecdotal disease 30 years ago. Its spread in Equatorial Africa and the side effects associated with mass drug administration programs against filariasis in co-endemic areas have drawn the attention of the international research community. Progress in research conducted to date has provided insight into the immunobiology of this parasite. An interesting finding reported in several studies is that 70% of individuals with loiasis do not carry microfilariae in their blood, and 30% are microfilaremic, suggesting the involvement of several immunological mechanisms, as shown by elevated specific IgG4 and IgE levels signifying a potential cross-linking mechanism between the two isotypes via L. loa antigen to prevent allergy. A mechanism of anergy in the appearance of microfilariae in the peripheral blood results in immunological unresponsiveness in individuals with microfilariae. There is an interaction between other pathogens (parasites, bacteria, viruses) in individuals co-infected with L. loa. The strong antigen cross-reactivity between L. loa and lymphatic filarial worms warrants a re-evaluation of the distribution of the latter in co-endemic regions. The mechanism of concomitant immunity observed in the elimination of microfilariae or infective larvae (third-stage larvae, L3) may be used for the conception of an immunoprophylactic strategy.
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Affiliation(s)
- Roland Dieki
- Department of Parasitology, International Centre of Medical Research of Franceville, Franceville, Gabon
- Department of Chemistry, Université des Sciences et Techniques de Masuku (USTM), Franceville, Gabon
| | - Edouard Nsi-Emvo
- Department of Chemistry, Université des Sciences et Techniques de Masuku (USTM), Franceville, Gabon
| | - Jean Paul Akue
- Department of Parasitology, International Centre of Medical Research of Franceville, Franceville, Gabon
- Correspondence: Jean Paul Akue, Department of Parasitology, International Centre of Medical Research of Franceville, Franceville, BP 769, Gabon, Email
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16
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Tamarozzi F, Buonfrate D, Ricaboni D, Ursini T, Foti G, Gobbi F. Spleen nodules in Loa loa infection: re-emerging knowledge and future perspectives. THE LANCET. INFECTIOUS DISEASES 2022; 22:e197-e206. [PMID: 35219405 DOI: 10.1016/s1473-3099(21)00632-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/24/2021] [Accepted: 09/28/2021] [Indexed: 06/14/2023]
Abstract
Loiasis, the infection with the vector-borne filarial nematode Loa loa, is widely distributed in central and west Africa. Long considered a rather benign infection, recently loiasis with high microfilarial burden was associated with increased mortality risk. Eyeworm and Calabar swelling are pathognomonic signs of the infection, but other atypical, non-specific manifestations can also occur. For instance, splenic nodules have been seldom reported. In this Grand Round, we report two cases of loiasis in migrants who presented with spleen nodules, which could be followed up over time (up to 27 months) with multiple imaging techniques until their resolution. We comment on the clinical implications of these observations, including differential diagnosis with similar imaging findings, and critically review the evidence of spleen involvement in loiasis and other filarial infections.
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Affiliation(s)
- Francesca Tamarozzi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Italy.
| | - Dora Buonfrate
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Italy
| | | | - Tamara Ursini
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Italy
| | - Giovanni Foti
- Department of Radiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Italy
| | - Federico Gobbi
- Department of Infectious-Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Italy
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Risch F, Ritter M, Hoerauf A, Hübner MP. Human filariasis-contributions of the Litomosoides sigmodontis and Acanthocheilonema viteae animal model. Parasitol Res 2021; 120:4125-4143. [PMID: 33547508 PMCID: PMC8599372 DOI: 10.1007/s00436-020-07026-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/20/2020] [Indexed: 12/16/2022]
Abstract
Filariae are vector-borne parasitic nematodes that are endemic worldwide, in tropical and subtropical regions. Important human filariae spp. include Onchocerca volvulus, Wuchereria bancrofti and Brugia spp., and Loa loa and Mansonella spp. causing onchocerciasis (river blindness), lymphatic filariasis (lymphedema and hydrocele), loiasis (eye worm), and mansonelliasis, respectively. It is estimated that over 1 billion individuals live in endemic regions where filarial diseases are a public health concern contributing to significant disability adjusted life years (DALYs). Thus, efforts to control and eliminate filarial diseases were already launched by the WHO in the 1970s, especially against lymphatic filariasis and onchocerciasis, and are mainly based on mass drug administration (MDA) of microfilaricidal drugs (ivermectin, diethylcarbamazine, albendazole) to filarial endemic areas accompanied with vector control strategies with the goal to reduce the transmission. With the United Nations Sustainable Development Goals (SDGs), it was decided to eliminate transmission of onchocerciasis and stop lymphatic filariasis as a public health problem by 2030. It was also requested that novel drugs and treatment strategies be developed. Mouse models provide an important platform for anti-filarial drug research in a preclinical setting. This review presents an overview about the Litomosoides sigmodontis and Acanthocheilonema viteae filarial mouse models and their role in immunological research as well as preclinical studies about novel anti-filarial drugs and treatment strategies.
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Affiliation(s)
- Frederic Risch
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany
| | - Manuel Ritter
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Marc P Hübner
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany.
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany.
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18
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Sandri TL, Kreidenweiss A, Cavallo S, Weber D, Juhas S, Rodi M, Woldearegai TG, Gmeiner M, Veletzky L, Ramharter M, Tazemda-Kuitsouc GB, Matsiegui PB, Mordmüller B, Held J. Molecular Epidemiology of Mansonella Species in Gabon. J Infect Dis 2021; 223:287-296. [PMID: 33099649 DOI: 10.1093/infdis/jiaa670] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/20/2020] [Indexed: 01/04/2023] Open
Abstract
Mansonella perstans, a filarial nematode, infects large populations in Africa and Latin America. Recently, a potential new species, Mansonella sp "DEUX," was reported. Carriage of endosymbiotic Wolbachia opens treatment options for Mansonella infections. Within a cross-sectional study, we assessed the prevalence of filarial infections in 834 Gabonese individuals and the presence of the endosymbiont Wolbachia. Almost half of the participants (400/834 [48%]) were infected with filarial nematodes, with Mansonella sp "DEUX" being the most frequent (295/400 [74%]), followed by Loa loa (273/400 [68%]) and Mansonella perstans (82/400 [21%]). Being adult/elderly, male, and living in rural areas was associated with a higher risk of infection. Wolbachia carriage was confirmed in M. perstans and Mansonella sp "DEUX." In silico analysis revealed that Mansonella sp "DEUX" is not detected with currently published M. perstans-specific assays. Mansonella infections are highly prevalent in Gabon and might have been underreported, likely also beyond Gabon.
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Affiliation(s)
- Thaisa Lucas Sandri
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Laboratory of Molecular Immunopathology, Department of Clinical Pathology, Federal University of Paraná, Curitiba, Brazil
| | - Andrea Kreidenweiss
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,German Center for Infection Research, partner site Tübingen, Tübingen, Germany
| | - Simon Cavallo
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - David Weber
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Sascha Juhas
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Miriam Rodi
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Tamirat Gebru Woldearegai
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,German Center for Infection Research, partner site Tübingen, Tübingen, Germany
| | - Markus Gmeiner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Luzia Veletzky
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine and I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine and I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | - Benjamin Mordmüller
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,German Center for Infection Research, partner site Tübingen, Tübingen, Germany
| | - Jana Held
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,German Center for Infection Research, partner site Tübingen, Tübingen, Germany
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19
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Mischlinger J, Manego RZ, Mombo-Ngoma G, Ekoka Mbassi D, Hackbarth N, Ekoka Mbassi FA, Davi SD, Kreuzmair R, Veletzky L, Hergeth J, Ndoumba WN, Pitzinger P, Groger M, Matsiegui PB, Adegnika AA, Agnandji ST, Lell B, Ramharter M. Diagnostic performance of capillary and venous blood samples in the detection of Loa loa and Mansonella perstans microfilaraemia using light microscopy. PLoS Negl Trop Dis 2021; 15:e0009623. [PMID: 34398886 PMCID: PMC8389422 DOI: 10.1371/journal.pntd.0009623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 08/26/2021] [Accepted: 07/03/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Loa loa and Mansonella perstans-the causative agents of loiasis and mansonellosis-are vector-borne filarial parasites co-endemic in sub-Saharan Africa. Diagnosis of both infections is usually established by microscopic analysis of blood samples. It was recently established that the odds for detecting Plasmodium spp. is higher in capillary (CAP) blood than in venous (VEN) blood. In analogy to this finding this analysis evaluates potential differences in microfilaraemia of L. loa and M. perstans in samples of CAP and VEN blood. METHODS Recruitment took place between 2015 and 2019 at the CERMEL in Lambaréné, Gabon and its surrounding villages. Persons of all ages presenting to diagnostic services of the research center around noon were invited to participate in the study. A thick smear of each 10 microliters of CAP and VEN blood was prepared and analysed by a minimum of two independent microscopists. Differences of log2-transformed CAP and VEN microfilaraemia were computed and expressed as percentages. Furthermore, odds ratios for paired data were computed to quantify the odds to detect microfilariae in CAP blood versus in VEN blood. RESULTS A total of 713 participants were recruited among whom 52% were below 30 years of age, 27% between 30-59 years of age and 21% above 60 years of age. Male-female ratio was 0.84. Among 152 participants with microscopically-confirmed L. loa infection median (IQR) microfilaraemia was 3,650 (275-11,100) per milliliter blood in CAP blood and 2,775 (200-8,875) in VEN blood (p<0.0001), while among 102 participants with M. perstans this was 100 (0-200) and 100 (0-200), respectively (p = 0.44). Differences in linear models amount up to an average of +34.5% (95% CI: +11.0 to +63.0) higher L. loa microfilaria quantity in CAP blood versus VEN blood and for M. perstans it was on average higher by +24.8% (95% CI: +0.0 to +60.5). Concordantly, the odds for detection of microfilaraemia in CAP samples versus VEN samples was 1.24 (95% CI: 0.65-2.34) and 1.65 (95% CI: 1.0-2.68) for infections with L. loa and M. perstans, respectively. CONCLUSION This analysis indicates that average levels of microfilaraemia of L. loa are higher in CAP blood samples than in VEN blood samples. This might have implications for treatment algorithms of onchocerciasis and loiasis, in which exact quantification of L. loa microfilaraemia is of importance. Furthermore, the odds for detection of M. perstans microfilariae was higher in CAP than in VEN blood which may pre-dispose CAP blood for detection of M. perstans infection in large epidemiological studies when sampling of large blood quantities is not feasible. No solid evidence for a higher odds of L. loa microfilariae detection in CAP blood was revealed, which might be explained by generally high levels of L. loa microfilaraemia in CAP and VEN blood above the limit of detection of 100 microfilariae/ml. Yet, it cannot be excluded that the study was underpowered to detect a moderate difference.
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Affiliation(s)
- Johannes Mischlinger
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
| | - Rella Zoleko Manego
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Ghyslain Mombo-Ngoma
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Dorothea Ekoka Mbassi
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
| | - Nina Hackbarth
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
| | - Franck-Aurelien Ekoka Mbassi
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Saskia Dede Davi
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
| | - Ruth Kreuzmair
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Luzia Veletzky
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
| | | | | | | | - Mirjam Groger
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
| | | | - Ayôla Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Germany
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Michael Ramharter
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
- * E-mail:
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20
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Ta-Tang TH, Luz SLB, Crainey JL, Rubio JM. An Overview of the Management of Mansonellosis. Res Rep Trop Med 2021; 12:93-105. [PMID: 34079424 PMCID: PMC8163967 DOI: 10.2147/rrtm.s274684] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 04/30/2021] [Indexed: 02/02/2023] Open
Abstract
Mansonellosis is caused by three filarial parasite species from the genus Mansonella that commonly produce chronic human microfilaraemias: M. ozzardi, M. perstans and M. streptocerca. The disease is widespread in Africa, the Caribbean and South and Central America, and although it is typically asymptomatic it has been associated with mild pathologies including leg-chills, joint-pains, headaches, fevers, and corneal lesions. No robust mansonellosis disease burden estimates have yet been made and the impact the disease has on blood bank stocks and the monitoring of other filarial diseases is not thought to be of sufficient public health importance to justify dedicated disease management interventions. Mansonellosis´s Ceratopogonidae and Simuliidae vectors are not targeted by other control programmes and because of their small size and out-door biting habits are unlikely to be affected by interventions targeting other disease vectors like mosquitoes. The ivermectin and mebendazole-based mass drug administration (iMDA and mMDA) treatment regimens deployed by the WHO´s Elimination of Neglected Tropical Diseases (ESPEN) programme and its forerunners have, however, likely impacted significantly on the mansonellosis disease burden, principally by reducing the transmission of M. streptocerca in Africa. The increasingly popular plan of using iMDA to control malaria could also affect M. ozzardi parasite prevalence and transmission in Latin America in the future. However, a potentially far greater mansonellosis disease burden impact is likely to come from short-course curative anti-Wolbachia therapeutics, which are presently being developed for onchocerciasis and lymphatic filariasis treatment. Even if the WHO´s ESPEN programme does not choose to deploy these drugs in MDA interventions, they have the potential to dramatically increase the financial and logistical feasibility of effective mansonellosis management. There is, thus, now a fresh and urgent need to better characterise the disease burden and eco-epidemiology of mansonellosis so that effective management programmes can be designed, advocated for and implemented.
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Affiliation(s)
- Thuy-Huong Ta-Tang
- Malaria and NTDs Laboratory, National Centre of Tropical Medicine, Instituto de Salud Carlos III, Madrid, Spain
| | - Sergio L B Luz
- Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz, Manaus, Amazonas State, Brazil
| | - James L Crainey
- Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz, Manaus, Amazonas State, Brazil
| | - José M Rubio
- Malaria & Emerging Parasitic Diseases Laboratory, National Microbiology Center, Instituto de Salud Carlos III, Madrid, Spain
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21
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Development of sustainable research excellence with a global perspective on infectious diseases: Centre de Recherches Médicales de Lambaréné (CERMEL), Gabon. Wien Klin Wochenschr 2021; 133:500-508. [PMID: 33398458 PMCID: PMC7781170 DOI: 10.1007/s00508-020-01794-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 11/30/2020] [Indexed: 11/17/2022]
Abstract
Medical research in sub-Saharan Africa is of high priority for societies to respond adequately to local health needs. Often enough it remains a challenge to build up capacity in infrastructure and human resources to highest international standards and to sustain this over mid-term to long-term periods due to difficulties in obtaining long-term institutional core funding, attracting highly qualified scientists for medical research and coping with ever changing structural and political environments. The Centre de Recherches Médicales de Lambaréné (CERMEL) serves as model for how to overcome such challenges and to continuously increase its impact on medical care in Central Africa and beyond. Starting off as a research annex to the Albert Schweitzer Hospital in Lambaréné, Gabon, it has since then expanded its activities to academic and regulatory clinical trials for drugs, vaccines and diagnostics in the field of malaria, tuberculosis, and a wide range of poverty related and neglected tropical infectious diseases. Advancing bioethics in medical research in Africa and steadily improving its global networks and infrastructures, CERMEL serves as a reference centre for several international consortia. In close collaboration with national authorities, CERMEL has become one of the main training hubs for medical research in Central Africa. It is hoped that CERMEL and its leitmotiv “to improve medical care for local populations” will serve as an inspiration to other institutions in sub-Saharan Africa to further increase African capacity to advance medicine.
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22
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Impact of Helminth Infections during Pregnancy on Vaccine Immunogenicity in Gabonese Infants. Vaccines (Basel) 2020; 8:vaccines8030381. [PMID: 32664597 PMCID: PMC7563176 DOI: 10.3390/vaccines8030381] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/06/2020] [Accepted: 07/08/2020] [Indexed: 01/13/2023] Open
Abstract
Helminth infections are common in sub-Saharan Africa. Besides direct clinical effects, a bias towards a T helper type 2 (Th2) cell immune response is observed. The consequences of parasite infection during pregnancy for the mother and particularly for the fetus and the newborn can be severe and may include impaired immune response during acute infection and vaccination. Here, we present data of immune responses to vaccines given within the expanded program on immunization (EPI) of infants born to helminth infected or non-infected mothers. The study was conducted in Lambaréné and surroundings, Gabon. Maternal helminth infection was diagnosed microscopically using the Kato-Katz method for soil-transmitted helminths (STH), urine filtration for Schistosoma haematobium infections and the saponin-based method for filarial infections. Plasma antibody levels to different vaccine antigens were measured in mothers and their offspring by enzyme-linked immunosorbent assay (ELISA) at different timepoints. We found 42.3% of the mothers to be infected with at least one helminth species. Significantly lower anti-tetanus toxoid immunoglobulin (Ig) G was detected in the cord blood of infants born to helminth infected mothers. Following vaccination, immune responses of the infants to EPI vaccines were similar between the two groups at nine and 12 months. Even though infection with helminths is still common in pregnant women in Gabon, in our setting, there was no evidence seen for a substantial effect on infants’ immune responses to vaccines given as part of the EPI.
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23
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Pion SD, Chesnais CB. Uncovering the burden of loiasis: first estimates from Gabon. THE LANCET. INFECTIOUS DISEASES 2020; 20:1226-1227. [PMID: 32585134 DOI: 10.1016/s1473-3099(20)30324-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 04/15/2020] [Indexed: 11/27/2022]
Affiliation(s)
- Sébastien D Pion
- Research Institute for Development, University of Montpellier, Montpellier 34394, France.
| | - Cédric B Chesnais
- Research Institute for Development, University of Montpellier, Montpellier 34394, France
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