Despite the broad distribution of M. ozzardi in Latin America and the Caribbean, there is still very little DNA sequence data available to study this neglected parasite’s epidemiology. Mitochondrial DNA (mtDNA) sequences, especially the cytochrome oxidase (CO1) gene’s barcoding region, have been targeted successfully for filarial diagnostics and for epidemiological, ecological and evolutionary studies. MtDNA-based studies can, however, be compromised by unrecognised mitochondrial pseudogenes, such as Numts. Here, we have used shot-gun Illumina-HiSeq sequencing to recover the first complete Mansonella genus mitogenome and to identify several mitochondrial-origin pseudogenes. Mitogenome phylogenetic analysis placed M. ozzardi in the Onchocercidae “ONC5” clade and suggested that Mansonella parasites are more closely related to Wuchereria and Brugia genera parasites than they are to Loa genus parasites. DNA sequence alignments, BLAST searches and conceptual translations have been used to compliment phylogenetic analysis showing that M. ozzardi from the Amazon and Caribbean regions are near-identical and that previously reported Peruvian M. ozzardi CO1 reference sequences are probably of pseudogene origin. In addition to adding a much-needed resource to the Mansonella genus’s molecular tool-kit and providing evidence that some M. ozzardi CO1 sequence deposits are pseudogenes, our results suggest that all Neotropical M. ozzardi parasites are closely related.
We obtained ribosomal and mitochondrial DNA sequences from residents of Amazonas state, Brazil, with Mansonella parasitemias. Phylogenetic analysis of these sequences confirm that M. ozzardi and M. perstans parasites occur in sympatry and reveal the close relationship between M. perstans in Africa and Brazil, providing insights into the parasite’s New World origins.
BackgroundAmerican cutaneous leishmaniasis (ACL) is a re-emerging disease in the state of São Paulo, Brazil. It is important to understand both the vector and disease distribution to help design control strategies. As an initial step in applying geographic information systems (GIS) and remote sensing (RS) tools to map disease-risk, the objectives of the present work were to: (i) produce a single database of species distributions of the sand fly vectors in the state of São Paulo, (ii) create combined distributional maps of both the incidence of ACL and its sand fly vectors, and (iii) thereby provide individual municipalities with a source of reference material for work carried out in their area.ResultsA database containing 910 individual records of sand fly occurrence in the state of São Paulo, from 37 different sources, was compiled. These records date from between 1943 to 2009, and describe the presence of at least one of the six incriminated or suspected sand fly vector species in 183/645 (28.4%) municipalities. For the remaining 462 (71.6%) municipalities, we were unable to locate records of any of the six incriminated or suspected sand fly vector species (Nyssomyia intermedia, N. neivai, N. whitmani, Pintomyia fischeri, P. pessoai and Migonemyia migonei). The distribution of each of the six incriminated or suspected vector species of ACL in the state of São Paulo were individually mapped and overlaid on the incidence of ACL for the period 1993 to 1995 and 1998 to 2007. Overall, the maps reveal that the six sand fly vector species analyzed have unique and heterogeneous, although often overlapping, distributions. Several sand fly species - Nyssomyia intermedia and N. neivai - are highly localized, while the other sand fly species - N. whitmani, M. migonei, P. fischeri and P. pessoai - are much more broadly distributed. ACL has been reported in 160/183 (87.4%) of the municipalities with records for at least one of the six incriminated or suspected sand fly vector species, while there are no records of any of these sand fly species in 318/478 (66.5%) municipalities with ACL.ConclusionsThe maps produced in this work provide basic data on the distribution of the six incriminated or suspected sand fly vectors of ACL in the state of São Paulo, and highlight the complex and geographically heterogeneous pattern of ACL transmission in the region. Further studies are required to clarify the role of each of the six suspected sand fly vector species in different regions of the state of São Paulo, especially in the majority of municipalities where ACL is present but sand fly vectors have not yet been identified.
Mansonella ozzardi and Mansonella perstans infections both cause mansonellosis but are usually treated differently. Using a real-time polymerase chain reaction assay and deep sequencing, we reveal the presence of mansonellosis coinfections that were undetectable by standard diagnostic methods. Our results confirm mansonellosis coinfections and have important implications for the disease’s treatment and diagnosis.
There are two species of filarial parasites with sheathless microfilariae known to commonly cause parasitaemias in humans: Mansonella perstans and Mansonella ozzardi. In most contemporary accounts of the distribution of these parasites, neither is usually considered to occur anywhere in the Eastern Hemisphere. However, Sir Patrick Manson, who first described both parasite species, recorded the existence of sheathless sharp-tailed Mansonella ozzardi-like parasites occurring in the blood of natives from New Guinea in each and every version of his manual for tropical disease that he wrote before his death in 1922. Manson's reports were based on his own identifications and were made from at least two independent blood sample collections that were taken from the island. Pacific region Mansonella perstans parasitaemias were also later (in 1923) reported to occur in New Guinea and once before this (in 1905) in Fiji. Although Mansonella-parasitaemias are generally regarded as benign, they are thought to be of public health importance because they can affect the epidemiological monitoring of other filarial diseases. In this article, we reviewed the historic literature concerning Pacific-origin Mansonella-parasitaemias in an attempt to explain how, despite repeated reports of Pacific-region Mansonella-parasitaemias, by as early as the 1970s, the WHO had arrived at the present-day view that Wuchereria bancrofti is the only cause of filarial parasitaemias in Papua New Guinea. We have also evaluated the evidence supporting the contemporary existence of Pacific-area parasitaemia-causing Mansonella parasites and assessed the relevance such parasites could have for present-day lymphatic filariasis elimination efforts in the region.
The primates that inhabit the rainforest surrounding the city of Manaus (Amazonas, Brazil) have long been recognised as potentially important reservoirs of emerging and re-emerging infectious diseases (ERIDs). PCR amplification of filarial sequences from wild-caught Simulium oyapockense has been used to incriminate potentially important Amazon-region ERID bridge vectors by showing they had previously fed on non-human primates. The broader use of filarial parasite sequences for the incrimination of biting insects as potentially important zoonotic disease vectors is limited by a paucity of primate-derived filarial parasite reference sequences which can be matched to the PCR amplified sequences obtained from insect-vector vectors. Here we have used shotgun sequencing to obtain reference data from an adult Dipetalonema gracile parasite which was found infecting a wild pied tamarin (Saguinus bicolor) in a peripheral region of Manaus. We report the parasite´s complete mitochondrial genome (which is 13,647 base pairs in length), 894,846 base pairs of its Wolbachia genome and 6,426 base pairs of its ribosomal DNA locus (spanning from the start of its 18S subunit to the end of its 28S subunit). Despite being critically endangered, S. bicolor is commonly encountered around the periphery of Manaus and in urban forest fragments. The reported sequences may be a useful reference tool for identifying ERID bridge vectors and potentially provide some insights into the amount and the nature of contact between primate pathogen reservoirs and the residents of Manaus.
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