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Research and Reports in Tropical... 2018Mansonellosis is a filarial disease caused by three species of filarial (nematode) parasites (, , and ) that use humans as their main definitive hosts. These parasites... (Review)
Review
Mansonellosis is a filarial disease caused by three species of filarial (nematode) parasites (, , and ) that use humans as their main definitive hosts. These parasites are transmitted from person to person by bloodsucking females from two families of flies (Diptera). Biting midges (Ceratopogonidae) transmit all three species of , but blackflies (Simuliidae) are also known to play a role in the transmission of in parts of Latin America. and are endemic in western, eastern, and central Africa, and is also present in the neotropical region from equatorial Brazil to the Caribbean coast. has a patchy distribution in Latin America and the Caribbean. Mansonellosis infections are thought to have little pathogenicity and to be almost always asymptomatic, but occasionally causing itching, joint pains, enlarged lymph glands, and vague abdominal symptoms. In Brazil, infections are also associated with corneal lesions. Diagnosis is usually performed by detecting microfilariae in peripheral blood or skin without any periodicity. There is no standard treatment at present for mansonellosis. The combination therapy of diethylcarbamazine plus mebendazole for microfilaremia is presently one of the most widely used, but the use of ivermectin has also been proven to be very effective against microfilariae. Recently, doxycycline has shown excellent efficacy and safety when used as an antimicrobial against endosymbiotic bacteria harbored by some strains of and . Diethylcarbamazine and ivermectin have been used effectively to treat infection. There are at present no estimates of the disease burden caused by mansonellosis, and thus its importance to many global health professionals and policy makers is presently limited to how it can interfere with diagnostic tools used in modern filarial disease control and elimination programs aimed at other species of filariae.
PubMed: 30050351
DOI: 10.2147/RRTM.S125750 -
New Microbes and New Infections Nov 2018Human mansonellosis is caused by and the three main filarial species in the genus Despite accumulating evidence of a high prevalence in endemic areas, there is... (Review)
Review
Human mansonellosis is caused by and the three main filarial species in the genus Despite accumulating evidence of a high prevalence in endemic areas, there is currently no filariasis control programme targeting mansonellosis. The health-related impact on people living with these filariae remains unknown, and evidences regarding treatment strategies are scarce. Like other neglected diseases, it mainly affects poor populations living in tropical and subtropical climates. Mansonellosis can be considered one of the most neglected tropical infectious diseases. The objective of this literature review was to draw attention to the gap of knowledge regarding spp. taxonomy, the transmission of these arthropod-borne filariasis and the health outcomes of people living with mansonellosis.
PubMed: 30402239
DOI: 10.1016/j.nmni.2018.08.016 -
Research and Reports in Tropical... 2021Mansonellosis is caused by three filarial parasite species from the genus that commonly produce chronic human microfilaraemias: and . The disease is widespread in... (Review)
Review
Mansonellosis is caused by three filarial parasite species from the genus that commonly produce chronic human microfilaraemias: and . 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 in Africa. The increasingly popular plan of using iMDA to control malaria could also affect 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- 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.
PubMed: 34079424
DOI: 10.2147/RRTM.S274684 -
Parasites & Vectors Dec 2023Loiasis is endemic in the northern and western part of the Republic of Congo. Between 2004 and 2010, surveys were conducted, using the RAPLOA method, in all departments...
BACKGROUND
Loiasis is endemic in the northern and western part of the Republic of Congo. Between 2004 and 2010, surveys were conducted, using the RAPLOA method, in all departments of the Republic of Congo to assess the distribution of loiasis. Prior to 2004, only two parasitological surveys on loiasis had been conducted in Congo and mainly in the Department of Lékoumou, in the southwestern of the country. In 2019, we conducted a parasitological survey in this same department, more than 30 years after the first surveys.
METHODS
The study was conducted in 21 villages. Loa loa and Mansonella perstans microfilaremia levels were quantified using 50 µl calibrated blood smears.
RESULTS
A total of 2444 individuals were examined. The median age of the screened individuals was 43 (interquartile range: 30-57, range: 18-91) years old. The overall prevalences of L. loa and M. perstans microfilaremia were 20.0% [95% confidence intervals (CI) 18.0-21.6%] and 1.0% (95% CI 0.6-1.4%) respectively. The proportion of individuals with a microfilarial density of L. loa > 8000 mf/ml and > 30,000 mf/ml were 5.1% (95% CI 4.3-6.1%) and 1.1% (95% CI 0.8-1.7%), respectively. The overall community microfilarial load was 3.4 mf/ml.
CONCLUSIONS
Prevalences and intensities of L. loa infection remained generally stable between the late 1980s and 2019 in the Lékoumou Department. In contrast, parasitological indicators for M. perstans have declined sharply in the intervening years for an unknown reason.
Topics: Animals; Humans; Adult; Middle Aged; Mansonella; Loiasis; Mansonelliasis; Loa; Congo; Prevalence; Microfilariae
PubMed: 38071391
DOI: 10.1186/s13071-023-06056-w -
Frontiers in Cellular and Infection... 2023species are filarial parasites that infect humans worldwide. Although these infections are common, knowledge of the pathology and diversity of the causative species is...
INTRODUCTION
species are filarial parasites that infect humans worldwide. Although these infections are common, knowledge of the pathology and diversity of the causative species is limited. Furthermore, the lack of sequencing data for species, shows that their research is neglected. Apart from Mansonella perstans, a potential new species called sp "DEUX" has been identified in Gabon, which is prevalent at high frequencies. We aimed to further determine if sp "DEUX" is a genotype of M. , or if these are two sympatric species.
METHODS
We screened individuals in the area of Fougamou, Gabon for Mansonella mono-infections and generated de novo assemblies from the respective samples. For evolutionary analysis, a phylogenetic tree was reconstructed, and the differences and divergence times are presented. In addition, mitogenomes were generated and phylogenies based on 12S rDNA and cox1 were created.
RESULTS
We successfully generated whole genomes for M. perstans and sp "DEUX". Phylogenetic analysis based on annotated protein sequences, support the hypothesis of two distinct species. The inferred evolutionary analysis suggested, that M. perstans and sp "DEUX" separated around 778,000 years ago. Analysis based on mitochondrial marker genes support our hypothesis of two sympatric human Mansonella species.
DISCUSSION
The results presented indicate that sp "DEUX" is a new species. These findings reflect the neglect of this research topic. And the availability of whole genome data will allow further investigations of these species.
Topics: Animals; Humans; Mansonella; Phylogeny; Sympatry; DNA, Ribosomal; Amino Acid Sequence
PubMed: 37124042
DOI: 10.3389/fcimb.2023.1159814 -
Infectious Diseases of Poverty Jul 2020Mansonella perstans infection can be considered one of the most neglected tropical infectious diseases. Very few studies have reported on the clinical picture caused by... (Comparative Study)
Comparative Study
BACKGROUND
Mansonella perstans infection can be considered one of the most neglected tropical infectious diseases. Very few studies have reported on the clinical picture caused by infection with this nematode. Therefore, our study was aimed to describe the clinical patterns and treatment of imported M. perstans infection by migrants from Africa.
METHODS
The present study evaluated a large cohort of migrants who have been diagnosed, examined and treated for imported M. perstans infection at a Spanish reference center (Hospital Carlos III Tropical Medicine Unit, Madrid, Spain) over a 19-year period. Most patients voluntarily attend the emergency unit or are referred from primary care or general hospitals in Madrid. Chi-square test was used to compare the association between categorical variables. The continuous variables were compared by Student's t-test or the Mann-Whitney test. The corresponding regression models were used for multivariate analysis.
RESULTS
Five hundred three cases of migrants from tropical and subtropical areas with M. perstans infection were identified. Two hundred sixty-four patients were female (52.5%). The mean age (± SD) was 44.6 ± 18.2 years (range: 16-93 years). The mean time (± SD) between the arrival in Spain and the first consultation was 8.6 ± 18.0 months. The major origin of the patients was Equatorial Guinea (97.6%). Regarding the clinical picture, 257 patients were asymptomatic (54.7%) and 228 were symptomatic (45.3%); 190 patients had pruritus (37.8%), 50 (9.9%) had arthralgia, 18 patients had Calabar-like swelling (3.6%), and 15 (3%) had abdominal pain. Four hundred forty-two (87.9%) migrants had hyper-IgE, and 340 (67.6%) had eosinophilia. One hundred ninety-five patients had coinfections with other filarial nematodes (38.8%), and 308 migrants had only M. perstans infection (61.2%). Four hundred thirty-seven cases (86.9%) had been treated with anti-filarial drugs; 292 cases were treated with one anti-filarial drug, and 145 cases were treated with combined anti-filarial therapy. Additionally, 20 (4%) cases received steroids and 38 (7.6%) cases received antihistamines.
CONCLUSIONS
A long series of M. perstans infections is presented in sub-Saharan immigrants whose data indicate that it should be included in the differential diagnosis in patients with pruritus or analytical alterations such as eosinophilia or hyper-IgE presentation, and they also have a high number of coinfections with other microorganisms whose treatment needs to be protocolized.
Topics: Adolescent; Adult; Africa; Aged; Aged, 80 and over; Animals; Antiparasitic Agents; Communicable Diseases, Imported; Female; Humans; Male; Mansonella; Mansonelliasis; Middle Aged; Spain; Transients and Migrants; Treatment Outcome; Young Adult
PubMed: 32703283
DOI: 10.1186/s40249-020-00729-9 -
Biomedicine & Pharmacotherapy =... May 2021Human filarial infections are vector-borne nematode infections, which include lymphatic filariasis, onchocerciasis, loiasis, and mansonella filariasis. With a high... (Review)
Review
Human filarial infections are vector-borne nematode infections, which include lymphatic filariasis, onchocerciasis, loiasis, and mansonella filariasis. With a high prevalence in developing countries, filarial infections are responsible for some of the most debilitating morbidities and a vicious cycle of poverty and disease. Global initiatives set to eradicate these infections include community mass treatments, vector control, provision of care for morbidity, and search for vaccines. However, there are growing challenges associated with mass treatments, vector control, and antifilarial vaccine development. With the emergence of genome editing tools and successful applications in other infectious diseases, the integration of genetic editing techniques in future control strategies for filarial infections would offer the best option for eliminating filarial infections. In this review, we briefly discuss the mechanisms of the three main genetic editing techniques and explore the potential applications of these powerful tools to control filarial infections.
Topics: Animals; CRISPR-Associated Protein 9; CRISPR-Cas Systems; Clustered Regularly Interspaced Short Palindromic Repeats; Filariasis; Filaricides; Filarioidea; Gene Editing; Genetic Therapy; Humans; Protozoan Vaccines
PubMed: 33581654
DOI: 10.1016/j.biopha.2021.111292 -
Data in Brief Feb 2020Endemic communities of infections have been neglected since associated pathology remains undefined. Consequently, improvements in drug therapy have also been ignored...
Endemic communities of infections have been neglected since associated pathology remains undefined. Consequently, improvements in drug therapy have also been ignored despite a large number of infected individuals in areas of Cameroon. Thus, we established an system to culture microfilariae (Mf); the transmission stage of infection. In short, we compared the ability of two renowned culture media (Dulbecco's Modified Eagle's Medium (DMEM) and Roswell Park Memorial Institute (RPMI-1640)) to sustain Mf in culture. Media were supplemented with 10% fetal bovine serum (FBS) and monkey kidney epithelial cells (LLC-MK) were used as feeder cells. As readout we assessed Mf survival and motility using a standardised microscopy assessment strategy. Moreover, this culture system was used to test susceptibility levels of microfilariae to different chemotherapeutic agents. Parasite motility was scored daily using a graded system and analysed using the average motility and area under the motility curve of Mf. These datasets were analysed and discussed in detail in the related article entitled: " maintenance of microfilariae and its relevance for drug screening" [1].
PubMed: 31886361
DOI: 10.1016/j.dib.2019.104930 -
Journal of Clinical Microbiology Oct 2019The morphologic similarities of the microfilariae and their infrequency in clinical specimens in settings of endemicity present challenges to clinical laboratories in... (Review)
Review
The morphologic similarities of the microfilariae and their infrequency in clinical specimens in settings of endemicity present challenges to clinical laboratories in maintaining competence for accurate identification and differentiation. We present here a review of the primary filarial nematodes causing human infection, including an illustrated key, which we hope will improve the diagnostic capabilities of hematologists, microbiologists, medical technologists, and similarly qualified laboratorians.
Topics: Animals; Humans; Immunoassay; Life Cycle Stages; Microfilariae; Microscopy; Molecular Diagnostic Techniques; Nematode Infections; Specimen Handling
PubMed: 31340993
DOI: 10.1128/JCM.00706-19 -
Parasites & Vectors Jan 2017Mansonellosis was first reported in Ghana by Awadzi in the 1990s. Co-infections of Mansonella perstans have also been reported in a small cohort of patients with Buruli...
BACKGROUND
Mansonellosis was first reported in Ghana by Awadzi in the 1990s. Co-infections of Mansonella perstans have also been reported in a small cohort of patients with Buruli ulcer and their contacts. However, no study has assessed the exact prevalence of the disease in a larger study population. This study therefore aimed to find out the prevalence of M. perstans infection in some districts in Ghana and to determine the diversity of Culicoides that could be potential vectors for transmission.
METHODS
From each participant screened in the Asante Akim North (Ashanti Region), Sene West and Atebubu Amantin (Brong Ahafo Region) districts, a total of 70 μl of finger prick blood was collected for assessment of M. perstans microfilariae. Centre for Disease Control (CDC) light traps as well as the Human Landing Catch (HLC) method were used to assess the species diversity of Culicoides present in the study communities.
RESULTS
From 2,247 participants, an overall prevalence of 32% was recorded although up to 75% prevalence was demonstrated in some of the communities. Culicoides inornatipennis was the only species of Culicoides caught with the HLC method. By contrast, C. imicola (47%), C. neavei (25%) and C. schultzei (15%) were caught by the CDC light trap method. A wide diversity of other Culicoides spp. was also identified but correlation was only found between the prevalence of C. inornatipennis and M. perstans during the dry season.
CONCLUSIONS
Here we demonstrate for the first time that M. perstans is highly prevalent in three districts in Ghana. We found a wide spectrum of Culicoides spp. Culicoides inornatipennis was the most anthropophilic and is therefore likely to be the species responsible for transmission of infection but formal proof has yet to be obtained.
TRIAL REGISTRATION
NCT02281643 . Registered October 26, 2014. 'Retrospectively registered'.
TRIAL REGISTRY
ClinicalTrials.gov.
Topics: Animals; Ceratopogonidae; Ghana; Humans; Insect Vectors; Mansonella; Mansonelliasis; Prevalence; Retrospective Studies
PubMed: 28061905
DOI: 10.1186/s13071-016-1960-0