This study analyzes 3,181 deaths from paracoccidioidomycosis in Brazil, based on 16 years of sequential data (from 1980 to 1995). During this period paracoccidioidomycosis showed considerable magnitude and low visibility, representing the eighth most common cause of death from predominantly chronic or recurrent types of infectious and parasitic diseases. It also had the highest mortality rate among the systemic mycoses. The mean annual mortality rate was 1.45 per million inhabitants, indicating a downward long-term trend (reduction of 31.28%), while spatial distribution among the different regions and States of Brazil was non-homogenous. The South (with the highest regional rate) and the Southeast showed a downward trend, while the Central West had the second highest rate in the country. At least one-fifth of Brazilian municipalities (or 22.71% of the country's total area) reported deaths from paracoccidioidomycosis. Overall nationwide mortality per area was 3.73/10,000km2. The disease was endemic in non-metropolitan areas. The majority of deaths occurred in males (84.75%), and there was a sex ratio of 562 men/100 women. The 30-59-year and over-60-year age groups were the most affected. The study showed that the mortality rate justifies classifying this disease as a major health problem in Brazil.
The pathogenic dimorphic fungus Sporothrix schenckii is the agent responsible for sporotrichosis, an important fungal infection with a worldwide distribution. Little is known about the population structure of S. schenckii, although recent molecular and phenotypic data seem to demonstrate that different genetic lineages exist within this species. The aim of this study was to determine, by sequence analysis of three protein coding loci (chitin synthase, -tubulin, and calmodulin), whether this variability is due to species divergence or intraspecific diversity in S. schenckii. We included in the analysis 60 isolates (59 of clinical and 1 of environmental origin) of this species from a wide geographical range. DNA sequence data from the three nuclear regions were used in a phylogenetic analysis. The combined analysis of the three loci revealed the presence of three major clades, one grouping all of the European isolates, another with only Brazilian isolates, and the third with isolates from other South American countries and Africa. A total of 14 100% bootstrap-supported nodes were shown, 6 of them representing putative phylogenetic species. Our data also demonstrated that most of these species prevail in different geographical regions.Sporothrix schenckii is a thermally dimorphic fungus responsible for sporotrichosis, a chronic granulomatous infection of the skin and subcutaneous tissues, although it can disseminate, affecting any organ of the human body (3). The infection is distributed worldwide, although it is more common in tropical and subtropical areas. Despite the clinical importance of S. schenckii, little is known about its basic biology and population structure. S. schenckii has its natural habitat in soil and plants, although it has been isolated from a variety of other sources (5,14,26). Recent molecular studies have demonstrated the existence of a high level of intraspecific variability and that isolates are mainly grouped according to their geographical origin (10,11,14,16). More recently, on the basis of internal transcribed spacer (ITS) region sequence analysis, it has been suggested that more than one species could exist within S. schenckii (27). Travassos and Lloyd (26) and Ghosh et al. (6) had also found morphological and physiological differences between isolates of clinical origin and those from other sources. Differences in virulence between clinical and environmental strains were reported, but no correlation was found with the different clinical forms of sporotrichosis (5,16,25). In this study, we have used DNA sequence data from multiple loci to assess the extent of clonality within a group of clinical isolates of S. schenckii from different geographic regions. Several molecular studies based on multiple gene sequences have demonstrated the existence of numerous phylogenetic species within well-established morphological species (4,7,17). However, the definition of phylogenetic species is controversial (13). Taylor et al. (24) argued that in the recognition of phylogenetic species, one-g...
The molecular types of 443 Brazilian isolates of Cryptococcus neoformans and Cryptococcus gattii were analyzed to determine their geographic distribution within Brazil and their underlying host conditions. The following data, imported from previous epidemiological studies as well as two culture collections, were analyzed for: place of isolation, source (clinical or environmental), host risk factors, species, serotype, mating type, and molecular type. Molecular typing by PCR-fingerprinting using primers for the minisatellite-specific core sequence of the wild-type phage M13 or microsatellites [(GACA)4, (GTG)5], restriction fragment length polymorphism of URA5 gene analysis, and/or amplified fragment length polymorphism (AFLP) identified eight major genotypes: VNI/AFLP1, VNII/AFLP1A, VNIII/AFLP2, and VNIV/AFLP3 for C. neoformans, and VGI/AFLP4, VGII/AFLP6, VGIII/AFLP5, and VGIV/AFLP7 for C. gattii. The most common molecular type found in Brazil was VNI (64%), followed by VGII (21%), VNII (5%), VGIII (4%), VGI and VNIV (3% each), and VNIII (< 1%). Primary cryptococcosis caused by the molecular type VGII (serotype B, MAT alpha) prevails in immunocompetent hosts in the North and Northeast regions, disclosing an endemic regional pattern for this specific molecular type in the Northern Brazil.
The emergence of distinct populations of Cryptococcus gattii in the temperate North American Pacific Northwest (PNW) was surprising, as this species was previously thought to be confined to tropical and semitropical regions. Beyond a new habitat niche, the dominant emergent population displayed increased virulence and caused primary pulmonary disease, as opposed to the predominantly neurologic disease seen previously elsewhere. Whole-genome sequencing was performed on 118 C. gattii isolates, including the PNW subtypes and the global diversity of molecular type VGII, to better ascertain the natural source and genomic adaptations leading to the emergence of infection in the PNW. Overall, the VGII population was highly diverse, demonstrating large numbers of mutational and recombinational events; however, the three dominant subtypes from the PNW were of low diversity and were completely clonal. Although strains of VGII were found on at least five continents, all genetic subpopulations were represented or were most closely related to strains from South America. The phylogenetic data are consistent with multiple dispersal events from South America to North America and elsewhere. Numerous gene content differences were identified between the emergent clones and other VGII lineages, including genes potentially related to habitat adaptation, virulence, and pathology. Evidence was also found for possible gene introgression from Cryptococcus neoformans var. grubii that is rarely seen in global C. gattii but that was present in all PNW populations. These findings provide greater understanding of C. gattii evolution in North America and support extensive evolution in, and dispersal from, South America.
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