RESUMO
BACKGROUND: Mansonellosis is an undermapped insect-transmitted disease caused by filarial nematodes that are estimated to infect hundreds of millions of people. Despite their prevalence, there are many outstanding questions regarding the general biology and health impacts of the responsible parasites. Historical reports suggest that the Colombian Amazon is endemic for mansonellosis and may serve as an ideal location to pursue these questions. METHODS: We deployed molecular and classical approaches to survey Mansonella prevalence among adults belonging to indigenous communities along the Amazon River and its tributaries near Leticia, Colombia. RESULTS: Loop-mediated isothermal amplification (LAMP) assays on whole-blood samples detected a much higher prevalence of Mansonella ozzardi infection (approximately 40%) compared to blood smear microscopy or LAMP performed using plasma, likely reflecting greater sensitivity and the ability to detect low microfilaremias and occult infections. Mansonella infection rates increased with age and were higher among men. Genomic analysis confirmed the presence of M. ozzardi that clusters closely with strains sequenced in neighboring countries. We successfully cryopreserved M. ozzardi microfilariae, advancing the prospects of rearing infective larvae in controlled settings. CONCLUSION: These data suggest an underestimation of true mansonellosis prevalence, and we expect that these methods will help facilitate the study of mansonellosis in endemic and laboratory settings.
Assuntos
Mansonelose , Parasitos , Masculino , Adulto , Animais , Humanos , Mansonella/genética , Mansonelose/epidemiologia , Mansonelose/parasitologia , Colômbia/epidemiologia , PrevalênciaRESUMO
We reviewed Giemsa-stained thick blood smears, obtained through the national malaria surveillance program in the Amazon region of Ecuador, by light microscopy for Mansonella spp. microfilariae. Of 2,756 slides examined, 566 (20.5%) were positive. Nested PCR confirmed that the microfilariae were those of M. ozzardi nematodes, indicating that this parasite is endemic to this region.
Assuntos
Mansonella , Mansonelose/epidemiologia , Mansonelose/parasitologia , Animais , Equador/epidemiologia , Feminino , Geografia Médica , Humanos , Masculino , Mansonella/genética , Mansonella/isolamento & purificação , Mansonelose/diagnóstico , Reação em Cadeia da Polimerase , Prevalência , Vigilância em Saúde PúblicaRESUMO
BACKGROUND: In the Brazilian Amazon, the filarial nematode Mansonella ozzardi co-exists with malaria parasites and thick blood smear microscopy is considered the diagnostic gold standard. Transfusion of M. ozzardi microfilariae does not establish new infections, however microfilariae can survive approximately 2 years in blood-recipients with unknown risk of pathology. Data on transfusion-transmitted filariasis are lacking. This study investigated M. ozzardi parasitemias in blood donors from decentralized centers of "Fundação Hematologia e Hemoterapia do Estado do Amazonas/HEMOAM," Northern Brazil. STUDY DESIGN AND METHODS: Cross-sectional investigation employing blood smear microscopy (n = 356) and qualitative nested-M. ozzardi-PCR (227 out of 356) in donor candidates from 19 hemocenters in interior/rural municipalities of Amazonas state. FINDINGS: Participants were mostly young males. Positivity by microscopy was 7.9% (28 out of 356) and 23.8% by M. ozzardi-PCR (54 out of 227). Parasitaemias were found in 16 out of 19 municipalities. In 54 M. ozzardi-positives, 24 were ineligible; among 30 that donated, 27 were interdicted by seropositivity (22 anti-HBc, 3 anti-HBc + HBsAg, 1 Chagas+malaria, 1 VDRL). Seropositivty was higher in M. ozzardi-PCR-positives vs M. ozzardi-PCR-negatives (OR = 15.8, 95% CI 4.5-56.1, p < 0.0001). Three M. ozzardi contaminated blood units were transfused, but no follow-up information on the recipients is available. MAIN CONCLUSIONS: Our study provides important baseline data on M. ozzardi among blood donors from the Brazilian Amazon. Further investigations in endemic areas are necessary to clarify possible association between M. ozzardi and other infections and also to elucidate whether there is any significant clinical effect upon transfusion of contaminated blood.
Assuntos
Doadores de Sangue/estatística & dados numéricos , Mansonella/patogenicidade , Mansonelose/parasitologia , Adolescente , Adulto , Idoso , Animais , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: The human filarial worm Mansonella ozzardi is highly endemic in the large tributaries of the Amazon River. This infection is still highly neglected and can be falsely negative when microfilariae levels are low. OBJECTIVES: This study investigated the frequency of individuals with M. ozzardi in riverine communities in Coari municipality, Brazilian Amazon. METHODS: Different diagnostic methods including polymerase chain reaction (PCR), blood polycarbonate membrane filtration (PCMF), Knott's method (Knott), digital thick blood smears (DTBS) and venous thick blood smears (VTBS) were used to compare sensitivity and specificity among the methods. Data were analysed using PCMF and Bayesian latent class models (BLCM) as the gold standard. We used BLCM to calculate the prevalence of mansonelliasis based on the results of five diagnostic methods. FINDINGS: The prevalence of mansonelliasis was 35.4% by PCMF and 30.1% by BLCM. PCR and Knott methods both possessed high sensitivity. Sensitivity relative to PCMF was 98.5% [95% confidence interval (CI): 92.0 - 99.7] for PCR and 83.5% (95% CI: 72.9 - 90.5) for Knott. Sensitivity derived by BLCM was 100% (95% CI 93.7 - 100) for PCMF, 100% (95% CI: 93.7 - 100) for PCR and 98.3% (95% CI: 90.6 - 99.9) for Knott. The odds ratio of being diagnosed as microfilaremic increased with age but did not differ between genders. Microfilariae loads were higher in subjects aged 30 - 45 and 45 - 60 years. MAIN CONCLUSIONS: PCMF and PCR were the best methods to assess the prevalence of mansonelliasis in our samples. As such, using these methods could lead to higher prevalence of mansonelliasis in this region than the most commonly used method (i.e., thick blood smears).
Assuntos
Mansonella/genética , Mansonelose/diagnóstico , Adolescente , Adulto , Idoso , Animais , Teorema de Bayes , Brasil/epidemiologia , Criança , Feminino , Filtração , Humanos , Masculino , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Pessoa de Meia-Idade , Cimento de Policarboxilato , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , População Rural , Sensibilidade e Especificidade , Manejo de Espécimes , Adulto JovemRESUMO
Haiti, like most limited-resources countries in the world, faces numerous neglected infectious diseases. They represent a real public health issue with lethal consequences especially in children. We are reviewing here the available literature on four neglected infectious diseases, mansonelliasis, tungiasis, leprosy and anthrax. Filariasis, due to Mansonella ozzardi, has been totally neglected since its discovery in 1920 in Haiti; it persists in coastal homes with a high prevalence in adults when an effective treatment is available. The skin lesions caused by Tunga penetrans have existed since the pre-Columbian period in Haiti. They persist in the most retreated and hard-to-reach areas where the population lives in precarious conditions and in extreme poverty. New available research data show the importance of the problem with very high prevalence rates in some rural communities far away from any healthcare center. Cases of leprosy are recently reemerging as no monitoring program has been in place since 2004. Finally, anthrax is still endemic; small epidemics resurfacing periodically in families in rural areas. Screening of people for these diseases and managing the cases are necessary to improve health and reduce morbidity and mortality in Haiti.
Comme dans la plupart des pays pauvres de la planète, les maladies infectieuses négligées sont nombreuses en Haïti où elles représentent un réel problème de santé publique avec des conséquences létales, surtout pour les enfants. Nous faisons le point des données accessibles pour quatre d'entre elles. Totalement délaissée depuis la découverte de sa présence en Haïti en 1920, la filariose due à Mansonella ozzardi persiste en foyers côtiers avec une prévalence élevée chez les adultes alors qu'un traitement efficace est disponible. Connues depuis la période précolombienne dans l'île d'Hispaniola, les lésions cutanées dues à Tunga penetrans persistent dans les régions les plus reculées et difficiles d'accès où la population vit dans des conditions précaires et dans une très grande pauvreté. Nous rapportons les données d'enquêtes récentes qui montrent l'importance de cette ectoparasitose en Haïti où les taux de prévalence sont très élevés dans certaines communautés rurales isolées. Des cas de lèpre resurgissent en Haïti alors qu'aucun programme de surveillance n'est effectif depuis 2004. Enfin, la maladie du charbon est endémique dans les régions d'élevage où des épidémies familiales resurgissent périodiquement en milieu rural. Le dépistage des personnes atteintes de ces maladies et leur prise en charge sont nécessaires pour une amélioration de la santé et une baisse de la mortalité en Haïti.
Assuntos
Antraz/epidemiologia , Hanseníase/epidemiologia , Mansonelose/epidemiologia , Doenças Negligenciadas/epidemiologia , Tungíase/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Feminino , Filariose/epidemiologia , Haiti/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto JovemRESUMO
Mansonella ozzardi (Nematoda: Onchocercidae) is a little studied filarial nematode. This human parasite, transmitted by two families of dipteran vectors, biting midges (most of them members of the genus Culicoides) and blackflies (genus Simulium), is endemic to the Neotropical regions of the New World. With a patchy geographical distribution from southern Mexico to north-western Argentina, human infection with M. ozzardi is highly prevalent in some of the Caribbean islands, along riverine communities in the Amazon Basin, and on both sides of the border between Bolivia and Argentina. Studies conducted in Haiti between 1974 and 1984 allowed the first complete description of the adult worm and permitted clarification of the taxonomic position of this filarial species. This paper reports the known geographical distribution of M. ozzardi in Neotropical regions of the Americas, and focuses on the current situation in Haiti where this filariasis remains a completely neglected public health problem.
Assuntos
Ceratopogonidae/parasitologia , Insetos Vetores/parasitologia , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Simuliidae/parasitologia , Animais , Haiti/epidemiologia , Humanos , Prevalência , Topografia MédicaRESUMO
Mansonella ozzardi (Nematoda: Onchocercidae) is an understudied filarial nematode, originally described by Patrick Manson in 1897, that can be transmitted by two families of dipteran vectors, biting midges (most of them members of the genus Culicoides) and black flies (genus Simulium). With a patchy geographic distribution from southern Mexico to northwestern Argentina, human infection with M. ozzardi is highly prevalent in some of the Caribbean islands, along riverine communities in the Amazon Basin, and on both sides of the border between Bolivia and Argentina. There is no clinical entity unequivocally associated with M. ozzardi infection, although fever, arthralgia, headache, cold lower extremities, and itchy cutaneous rashes are occasionally mentioned in case report series. More recently, ocular manifestations (especially keratitis) have been associated with mansonelliasis, opening an important area of investigation. Here, we briefly review the biology, epidemiology, pathogenesis, and clinical aspects of M. ozzardi infection and point to some existing knowledge gaps, aiming to stimulate a research agenda to help filling them.
Assuntos
Mansonella , Mansonelose/epidemiologia , Mansonelose/parasitologia , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/parasitologia , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Vetores Artrópodes/classificação , Vetores Artrópodes/parasitologia , Humanos , Mansonella/efeitos dos fármacos , Mansonella/crescimento & desenvolvimento , Mansonella/isolamento & purificação , Mansonella/fisiologia , Mansonelose/diagnóstico , Mansonelose/terapia , Doenças Negligenciadas/diagnóstico , Doenças Negligenciadas/terapia , PrevalênciaRESUMO
Mansonellosis is endemic in several regions of Africa, the Caribbean, and Latin America. Mansonella ozzardi and Mansonella perstans have been reported in Latin America, including the Amazon region. A morphological and molecular microfilariae study was performed in Pauini (Brazil). Blood samples were collected from 40 individuals, and were analyzed by Giemsa-stained blood film and by two different nested polymerase chain reactions which detect internal transcribed spacer-1 and the major sperm protein gene. By microscopy, 14 of 40 were positive: 11 as M. ozzardi and three as M. perstans-like infections. Both molecular methods detected 19 positive cases as M. ozzardi, including those 14 individuals detected by microscopy, without detectable genetic differences among any of the 19 positive samples. Molecular techniques showed an improvement of mansonellosis diagnosis and may become an effective tool to evaluate the present status of M. ozzardi and M. perstans in Latin America.
Assuntos
Mansonella , Mansonelose/parasitologia , Microfilárias , Animais , Brasil/epidemiologia , Humanos , Mansonella/genética , Mansonella/ultraestrutura , Mansonelose/diagnóstico , Mansonelose/epidemiologia , Microfilárias/genética , Microfilárias/ultraestrutura , Microscopia , Filogenia , Reação em Cadeia da PolimeraseRESUMO
46 especies de la familia Ceratopogonidae se han registrado en Misiones. Algunas especies son importantes polinizadoras, otras son depredadores importantes de organismos en hábitats semiacuáticos y acuáticos y otras se las utiliza como bioindicadores de calidad del agua. Las hembras adultas de Culicoides y Forcipomyia son hematófagos de vertebrados incluyendo al humano. Estos ceratopogónidos producen molestias por sus picaduras y los que presentan mayor importancia, hasta ahora potencial, en Argentina son los de género Culicoides sp, en donde hay especies de importancia médico-veterinaria. El estudio tiene por objetivo la identificación y caracterización de criaderos de ceratopogónidos de importancia sanitaria y económica para la zona sur de Misiones. Este trabajo corresponde a un estudio de tipo descriptivo en el área de la taxonomía de la familia Ceratopogonidae. Se realizó entre mayo 2016 y 2017 en el Centro de Investigaciones Entomológica. Se recolectaron larvas en 24 puntos determinados, se registraron datos ambientales y parámetros físico-químicos para la caracterización de los criaderos y se clasificó taxonómicamente a los individuos adultos con claves taxonómicas de Borkent y Spinelli (2007) y Spinelli et al (2005). Culicoides debilipalpis se colectó en criadero de ambiente fitotélmico en el Parque Profundidad en enero de 2017. Esta especie está incriminada en la transmisión de mansonelosis. El género Culicoides sp. se colectó en ambiente fitotélmico, en hueco de árbol, en ARA-El Zaimán y la Estancia Santa Inés, y en las axila de bromelia en el ARA-El Zaimán. La especie Alluaudomyia schnacki y los géneros Stilobezzia, y Atrichpogon se colectaron en ambientes lenticos. El género Forcipomyia, se colecto en ambientes fitotélmicos y lenticos. Es necesario ampliar el área de muestreo valiéndose de las características de criaderos relevadas en este trabajo, para poder identificar con mayor precisión posibles sitios de cría de esta familia
Assuntos
Qualidade da Água , Ceratopogonidae , Mansonelose , Mansonelose/epidemiologiaRESUMO
INTRODUCTION Mansonella ozzardi is a widely distributed filaria worm in the Amazon region. This study aimed to determine the prevalence of M. ozzardi infection in riverine communities of Lábrea municipality, Amazonas State, Brazil. METHODS A diagnostic blood filtration method in a polycarbonate membrane was used. RESULTS M. ozzardi was found in 50.3% of the sample, with the highest prevalence in farmers/fishermen (69.4%; χ 2 = -19.14, p<0.001). The prevalence was higher in longer-term residents (≥11 years; 60.2%). CONCLUSIONS M. ozzardi infection rates are high near the Purus River, much greater than those previously reported based on diagnosis using thick blood smears.