An atypical microfilaria in blood samples from inhabitants of Brazilian Amazon

Abstract

An unidentified microfilaria sharing characteristics with Mansonella ozzardi and Onchocerca volvulus was detected in blood samples from seven human volunteers, inhabitants of a community in the border of Amazonas and Acre State. They were detected during epidemiological studies carried out in some communities along Antimary, Acre, and Purus Rivers in the Brazilian Amazon. The most striking difference was presented in the shape of the cephalic space from this microfilaria which was different from those of M. ozzardi and with similarities to O. volvulus in this region, but no remarkable differences were observed at the caudal region. More accurate studies are being carried out in order to provide additional data and supporting evidences before establishment of a new species can be done.

Genetic Characterization of Atypical Mansonella (Mansonella) ozzardi Microfilariae in Human Blood Samples from Northeastern Peru

“…Of note, the atypical Mf previously reported from Brazil was described as being similar in size to M. ozzardi, with lengths of 198-247 μm. 4 Previous studies have reported variable lengths for M. ozzardi Mf from South America (between 149 and 228 μm).…”

“…These Mf include Microfilaria bolivarensis in Venezuela, 3 a microfilaria sharing characteristics with M. ozzardi and O. volvulus in Brazil, 4 and an atypical Mf recently reported from Peru. 5 The atypical Mf reported from Brazil and Peru were morphologically similar, with two nuclei followed by a single nucleus just caudal to the cephalic space.…”

“…This finding is in contrast to Mf of M. ozzardi, which have a single nucleus in this position. 4,5 The geographic distance between the communities where these atypical Mf were detected is approximately 850 km, and both areas are within M. ozzardi-endemic zones. 6 Additional studies were warranted to investigate whether the atypical Mf are from a novel filarial parasite species.…”

Mansonella ozzardi in Amazonas, Brazil: prevalence and distribution in the municipality of Coari, in the middle Solimões River

“…The first epidemiological survey for mansonelliasis in the municipality of Coari, AM, Brazil, was conducted by Rachou (1957), who found a prevalence rate of 10% for M. ozzardi; therefore, the present investigation is aimed at estimating the prevalence of M. ozzardi in both rural and urban areas of this municipality, assessing clinical manifestations of the disease and identifying the vector of M. ozzardi and its parasitic infection rate (PIR). Although this filariasis is a very neglected disease, since the 1950s, researchers have been calling attention to the high rates of infection (Rachou 1954, Lacerda & Rachou 1956, Oliveira 1961, Shelley 1975, Moraes et al 1978, Tavares 1981, Adami et al 2008, 2009b. The controversy over symptoms and the absence of a permanent health assistance as well as orientation for treatment and prophylaxis is continuing.…”

Mansonelosis por Mansonella ozzardi en voluntarios para despistaje de malaria en la Amazonía peruana

“…Recientemente Arróspide et al (10,25) notificaron en muestras de sangre de personas residentes en comunidades del río Nanay, la existencia de una variedad de Mansonella a la que se denominó atípica debido a la disposición ligeramente diferente de los primeros núcleos detrás del espacio cefálico. Estudios filogenéticos moleculares establecieron que se trataba de especies de M. ozzardi que estarían atravesando un proceso de la variación natural de la especie.…”