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Memorias Do Instituto Oswaldo Cruz May 2010This study investigated some epidemiological aspects of the Mansonella ozzardi in municipality of Coari, Amazonas. Clinical symptoms were correlated with the filarial...
This study investigated some epidemiological aspects of the Mansonella ozzardi in municipality of Coari, Amazonas. Clinical symptoms were correlated with the filarial infection and the parasitic infection rates (PIR) were estimated in simuliid vectors. The general M. ozzardi human prevalence rate was 13.3% (231/1733), of which 10.2% (109/1069) were from the urban area and 18.4% (122/664) from the rural area. The prevalence rates were higher in men (14.5% urban and 19.7% rural) than in women (6.7% urban and 17.2% rural) and occurred in most age groups. The indices of microfilaremics were higher in people > or = 51 years old (26.9% urban and 61.5% rural). High prevalence rates were observed in retired people (27.1% urban area), housewives and farmer (41.6% and 25%, respectively, in rural area). The main clinical symptoms were joint pains and sensation of leg coldness. Only Cerqueirellum argentiscutum (Simuliidae) transmits M. ozzardi in this municipality (PIR = 5.6% urban and 7.1% rural). M. ozzardi is a widely distributed parasitic disease in Coari. Thus, temporary residency in the region of people from other localities involved with the local gas exploitation might be a contributing factor in spreading the disease.
Topics: Adolescent; Adult; Age Distribution; Animals; Brazil; Child; Child, Preschool; Female; Humans; Infant; Insect Vectors; Male; Mansonella; Mansonelliasis; Middle Aged; Prevalence; Rural Population; Sex Distribution; Simuliidae; Urban Population; Young Adult
PubMed: 20512236
DOI: 10.1590/s0074-02762010000300002 -
Revista Da Sociedade Brasileira de... 2011Mansonelliasis is caused by Mansonella ozzardi. It is widespread in the Amazon region, with a high prevalence. The common exam of thick blood smears stained with Giemsa... (Comparative Study)
Comparative Study
INTRODUCTION
Mansonelliasis is caused by Mansonella ozzardi. It is widespread in the Amazon region, with a high prevalence. The common exam of thick blood smears stained with Giemsa shows low efficacy levels and has been an obstacle to diagnosing individuals with low blood parasitemia.
METHODS
In order to increase diagnosis efficacy, the PCR technique was improved.
RESULTS AND CONCLUSIONS
PCR demonstrated the best performance, with sensitivity and negative predictive values (NPV) of 100%, followed by blood filtration through membrane filters, which showed a sensitivity of 88.9% and a NPV of 84.6%, when compared to thick blood smears.
Topics: Animals; Humans; Mansonella; Mansonelliasis; Polymerase Chain Reaction; Predictive Value of Tests; Sensitivity and Specificity
PubMed: 21779677
DOI: 10.1590/s0037-86822011000300023 -
Revista Da Sociedade Brasileira de... 2014This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tefé River, Amazonas, Brazil.
INTRODUCTION
This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tefé River, Amazonas, Brazil.
METHODS
The prevalence of M. ozzardi was estimated by microscopic examination of thick blood smears.
RESULTS
The M. ozzardi prevalence rate was 6.3% (19/300). Filarial infection was found in 8 of the 11 communities surveyed, with prevalence rates varying from 2.5% to 22.2%.
CONCLUSIONS
Tefé is a region of oil and natural gas exploration, in which there is a high turnover of workers. Migration patterns may facilitate the dissemination of mansonelliasis to other regions.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Brazil; Child; Child, Preschool; Female; Humans; Male; Mansonella; Mansonelliasis; Middle Aged; Prevalence; Rivers; Rural Population; Young Adult
PubMed: 24553803
DOI: 10.1590/0037-8682-0031-2012 -
Clinical and Experimental Immunology Mar 2007The recommended control option against onchocerciasis is repeated ivermectin treatment, which will need to be implemented for decades, and it remains unknown how...
The recommended control option against onchocerciasis is repeated ivermectin treatment, which will need to be implemented for decades, and it remains unknown how repeated ivermectin therapy might affect immunity against Onchocerca volvulus in the long term. O. volvulus-specific antibody reactivity and cellular cytokine production were investigated in onchocerciasis patients receiving ivermectin (150 microg/kg) annually for 16 years. In treated patients, the T helper type 2 (Th2) cytokine interleukin (IL)-5 and T regulatory IL-10 in response to O. volvulus antigen (OvAg) and bacteria-derived Streptolysin O (SL-O) diminished to levels found in infection-free endemic controls; also, cellular release of Th1-type interferon (IFN)-gamma at 16 years post initial ivermectin treatment (p.i.t.) approached control levels. In ivermectin-treated onchocerciasis patients, IL-5 production in responses to the mitogen phytohaemagglutinin (PHA) decreased, but IL-10 in response PHA increased, and neither attained the cytokine production levels of endemic controls. At 16 years p.i.t., O. volvulus-specific IgG1 and IgG4 subclass reactivity still persisted at higher levels in onchocerciasis patients than in O. volvulus exposed but microfilariae-free endemic controls. In addition, cytokine responses remained depressed in onchocerciasis patients infected concurrently with Mansonella perstans and Necator americanus or Entamoeba histolytica/dispar. Thus, long-term ivermectin therapy of onchocerciasis may not suffice to re-establish fully a balanced Th1 and Th2 immune responsiveness in O. volvulus microfilariae-negative individuals. Such deficient reconstitution of immune competence may be due to an as yet continuing and uncontrolled reinfection with O. volvulus, but parasite co-infections can also bias and may prevent the development of such immunity.
Topics: Adult; Aged; Animals; Anthelmintics; Antibodies, Helminth; Cells, Cultured; Cytokines; Drug Administration Schedule; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunocompetence; Immunoglobulin G; Ivermectin; Male; Mansonelliasis; Middle Aged; Necatoriasis; Onchocerca volvulus; Onchocerciasis
PubMed: 17302900
DOI: 10.1111/j.1365-2249.2006.03312.x -
Emerging Infectious Diseases Jun 2014During August 2010-December 2012, we conducted a study of patients in Ghana who had Buruli ulcer, caused by Mycobacterium ulcerans, and found that 23% were co-infected...
During August 2010-December 2012, we conducted a study of patients in Ghana who had Buruli ulcer, caused by Mycobacterium ulcerans, and found that 23% were co-infected with Mansonella perstans nematodes; 13% of controls also had M. perstans infection. M. perstans co-infection should be considered in the diagnosis and treatment of Buruli ulcer.
Topics: Adolescent; Adult; Animals; Buruli Ulcer; Child; Coinfection; Female; Ghana; Humans; Incidence; Male; Mansonella; Mansonelliasis; Middle Aged; Mycobacterium ulcerans; Retrospective Studies
PubMed: 24857346
DOI: 10.3201/eid2006.131501 -
The American Journal of Tropical... Mar 2018The treatment of mansonelliasis is still a challenge because there are few clinical trials for the treatment of the disease. This double-blind, randomized,... (Randomized Controlled Trial)
Randomized Controlled Trial
The treatment of mansonelliasis is still a challenge because there are few clinical trials for the treatment of the disease. This double-blind, randomized, placebo-controlled study (phase III clinical trial) was conducted to evaluate the effectiveness of a single oral dose of ivermectin (0.15 mg/kg) in the reduction of the microfilaraemia and the occurrence of adverse effects in infected people compared with the control group treated with placebo. A total of 49 microfilaraemic patients were randomly selected from the municipality of Lábrea, State of Amazonas, in the Brazilian Amazon. Among them, 40 patients have concluded the study, 19 treated with ivermectin and 21 treated with placebo. In the first and third days after the treatment, all the patients were clinically evaluated, and the diagnostic and quantification of blood microfilariae through blood filtration in polycarbonate membranes was performed. A significant reduction of the microfilaraemia (99.9%) was observed in the patients who received ivermectin. Slight changes in laboratory test results, without clinical importance, were seen in treated and control groups. Our results suggest that ivermectin is effective and safe for the treatment of infections caused by .
Topics: Administration, Oral; Adolescent; Adult; Animals; Anthelmintics; Brazil; Double-Blind Method; Drug Administration Schedule; Female; Humans; Ivermectin; Male; Mansonella; Mansonelliasis; Microfilariae; Middle Aged; Treatment Outcome
PubMed: 29313486
DOI: 10.4269/ajtmh.17-0698 -
Parasites & Vectors May 2016Mansonellosis remains one of the most neglected of tropical diseases and its current distribution in the entire forest block of southern Cameroon is unknown. In order to...
BACKGROUND
Mansonellosis remains one of the most neglected of tropical diseases and its current distribution in the entire forest block of southern Cameroon is unknown. In order to address this issue, we have surveyed the distribution of Mansonella perstans in different bioecological zones and in addition, elucidated the influence of multiple rounds of ivermectin (IVM) based mass drug administration (MDA).
METHODS
A mixed design was used. Between 2000 and 2014, both cross-sectional and longitudinal surveys were carried out in 137 communities selected from 12 health districts belonging to five main bioecological zones of the southern part of Cameroon. The zones comprised of grassland savanna (GS), mosaic forest savanna (MFS), forested savanna (FS), deciduous equatorial rainforest (DERF) and the dense humid equatorial rainforest (DHERF). The survey was carried out in some areas with no treatment history as well as those currently under IVM MDA. Individuals within the participatory communities were screened for the presence of M. perstans microfilariae (mf) in peripheral blood by the calibrated thick film method to determine both prevalence and geometric mean intensities at the community level.
RESULTS
Apart from sporadic cases in savanna areas, distribution of M. perstans was strongly linked to the equatorial rainforest zones. Before CDTI, the highest mean prevalence (70.0 %) and intensity (17,382.2 mf/ml) were obtained in communities in Mamfes' DHERF areas followed by communities in the DHERF zone of Lolodorf (53.8 % and 7,814.8 mf/ml, respectively). A longitudinal survey in Mamfe further showed that M. perstans infections had reduced by 34.5 % in DERF (P < 0.001) but not DHERF zones after ten years of IVM MDA. Further data from the cross-sectional study revealed that there was a decrease in prevalence in DHERF zones only after ten years of MDA. In DERF zones however, the infection was relatively lower after four years of MDA.
CONCLUSIONS
The distribution of M. perstans in the southern part of Cameroon varies with bioecological zones and IVM MDA history. The zones with high prevalence and intensities lie in forested areas while those with low endemicity are in the savanna areas. MDA with ivermectin induced significant reduction in the endemicity of mansonellosis in the decidious equatorial rainforest. In contrast, the prevalence and intensity remained relatively high and stable in the dense humid equatorial rainforest zones even after a decade of mass drug administration with ivermectin. Since it is known that M. perstans down-regulates host's immune system, the findings from this work would be useful in designing studies to understand the impact of M. perstans on host immune response to vaccination and co-infection with other pathogens such as Mycobacterium spp. and Plasmodium spp. in areas of contrasting endemicities.
Topics: Animals; Cameroon; Cross-Sectional Studies; Endemic Diseases; Female; Forests; Geography; Humans; Insecticides; Ivermectin; Longitudinal Studies; Male; Mansonella; Mansonelliasis; Microfilariae; Neglected Diseases; Population Density; Prevalence; Rainforest
PubMed: 27245442
DOI: 10.1186/s13071-016-1595-1 -
Malaria Journal Jul 2013A case of co-infection with Plasmodium vivax and Mansonella ozzardi was detected in a blood sample from a person who had shown symptoms of malaria and lived in a city...
A case of co-infection with Plasmodium vivax and Mansonella ozzardi was detected in a blood sample from a person who had shown symptoms of malaria and lived in a city that was close to the Argentina/Bolivia border. The case was detected during a random revision of thick and thin smears from patients diagnosed with malaria from various towns and cities located in north-western Argentina between 1983 and 2001. Trophozoites of P. vivax were observed in the thin blood smear along with M. ozzardi microfilaria (larval form), which presented a long, slender, pointed anucleate tail and the absence of the sheath. This last characteristic is shared with Mansonella perstans, Mansonella streptocerca and Onchocerca volvulus. More rigorously controlled studies to detect other co-infection cases in the area as well as the possibility of importation from Bolivia into Argentina are currently ongoing. The relationship between the malaria parasite and microfilaria, the potential effect of malaria treatment on the development of M. ozzardi, and the possible impact of this microfilaria on the immunity of a person against P. vivax are all still unknown. This contribution constitutes a point of focus for future studies involving the interaction between the parasites and the potential risk that humans are exposed to.
Topics: Aged; Animals; Argentina; Blood; Coinfection; Humans; Malaria, Vivax; Male; Mansonella; Mansonelliasis; Plasmodium vivax
PubMed: 23866313
DOI: 10.1186/1475-2875-12-248 -
The New England Journal of Medicine Oct 2009Mansonella perstans infection is common in areas of Africa where Wuchereria bancrofti, a causative agent of lymphatic filariasis, is endemic. M. perstans is refractory... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Mansonella perstans infection is common in areas of Africa where Wuchereria bancrofti, a causative agent of lymphatic filariasis, is endemic. M. perstans is refractory to standard antifilarial therapies. The recent discovery of bacterial endosymbionts (e.g., wolbachia) in most filarial species, including M. perstans, provides new therapeutic options for reducing microfilaremia.
METHODS
In an open-label, randomized trial, we recruited subjects with M. perstans microfilaremia, with or without concomitant W. bancrofti infection, from four villages in Mali and randomly assigned them to receive doxycycline, at a dose of 200 mg daily for 6 weeks (106 subjects), or no treatment (110). At 6 months, subjects who were coinfected with W. bancrofti underwent a second random assignment, to treatment with a single dose of albendazole (400 mg) and ivermectin (150 microg per kilogram of body weight) or no treatment. Subjects were monitored daily during the first 6-week study period for adverse events. M. perstans and W. bancrofti microfilarial levels were assessed at 6, 12, and 36 months.
RESULTS
At 12 months, 67 of 69 subjects who had received treatment with doxycycline only (97%) had no detectable M. perstans microfilariae per 60 microl of blood, as compared with 10 of 63 subjects who had received no treatment (16%) (relative risk, 6.18; 95% confidence interval, 3.63 to 11.89; P<0.001). At 36 months, M. perstans microfilaremia remained suppressed in 48 of 64 subjects who had received treatment with doxycycline only (75%), a finding that was consistent with a macrofilaricidal effect of doxycycline. Vomiting was more frequent in the doxycycline-treated group than in the untreated group (17% vs. 4%).
CONCLUSIONS
These results are consistent with previous findings that M. perstans harbors the intracellular endosymbiont, wolbachia, and suggest that doxycycline is an effective therapy for M. perstans infection. (ClinicalTrials.gov number, NCT00340691.)
Topics: Adolescent; Adult; Aged; Albendazole; Animals; Anti-Bacterial Agents; Doxycycline; Drug Therapy, Combination; Elephantiasis, Filarial; Female; Filaricides; Humans; Ivermectin; Male; Mansonella; Mansonelliasis; Middle Aged; Rickettsiaceae Infections; Symbiosis; Treatment Outcome; Wolbachia; Wuchereria bancrofti; Young Adult
PubMed: 19812401
DOI: 10.1056/NEJMoa0900863 -
Journal of Vector Borne Diseases Mar 2011The study was aimed at elucidating the prevalence and intensity of Mansonella perstans microfilaraemia in the Emohua Local Government Area, Nigeria, and ascertaining the...
BACKGROUND & OBJECTIVES
The study was aimed at elucidating the prevalence and intensity of Mansonella perstans microfilaraemia in the Emohua Local Government Area, Nigeria, and ascertaining the abundance, circadian, and the annual biting patterns of the Culicoides vector.
METHODS
Thick smear of 50 µl finger-prick blood stained with Giemsa was examined microscopically in a cross-sectional study. Vector landing collection on human bait was employed in a longitudinal study of the vector biting patterns, carried out between July 2005 and August 2006.
RESULTS
Of 1486 individuals examined, 11.2% of both males and females were positive for M. perstans microfilaraemia. Microfilaraemia appeared early in life. The overall geometric mean intensity among those with positive microfilaraemia was 117 mf/ml (121 mf/ml for males and 113 mf/ml for females). The differences in geometric mean intensity between different age groups were statistically significant (one-way analysis of variance; p <0.05), being highest in the oldest age group (266 mf/ml). A total of 1183 female Culicoides sp were caught from September 2005 to August 2006. The abundance of Culicoides sp was seasonal. The circadian biting activity had a broad peak between 0700 and 1200 hrs. The monthly biting rates ranged from zero bite per person per month in January 2006 to 1151 bites per person per month in June 2006. The annual biting rate was 7382 bites per person per year.
CONCLUSION
Majority of those with positive microfilaraemia were poor socioeconomically, underscoring the need for health education and application of effective control measures against Culicoides biting midges in Emohua.
Topics: Adolescent; Adult; Aged; Animals; Ceratopogonidae; Child; Child, Preschool; Cross-Sectional Studies; Endemic Diseases; Female; Humans; Infant; Insect Bites and Stings; Insect Vectors; Local Government; Longitudinal Studies; Male; Mansonella; Mansonelliasis; Middle Aged; Nigeria; Parasitemia; Prevalence; Seasons; Young Adult
PubMed: 21406736
DOI: No ID Found