Project description:Cryptosporidium skunk genotype is a zoonotic pathogen commonly identified in surface water. Thus far, no subtyping tool exists for characterizing its transmission in humans and animals and transport in environment. In this study, a subtyping tool based on the 60kDa glycoprotein (gp60) gene previously developed for Cryptosporidium chipmunk genotype I was used in the characterization of Cryptosporidium skunk genotype in animal and storm runoff samples from a watershed in New York. Altogether, 17 positive samples from this watershed and 5 human and animal specimens from other areas were analyzed. We identified 14 subtypes of Cryptosporidium skunk genotype, 11 of which were seen in the watershed. In phylogenetic analysis, these subtypes belonged to 4 subtype families (XVIa, XVIb, XVIc, and XVId). No host-adapted subtypes were identified and the two subtypes in humans were genetically similar to some in raccoons, otters, and storm runoff samples from the watershed. The characteristics of gp60 protein sequences of the Cryptosporidium skunk genotype are similar to those of other Cryptosporidium species, but only its XVIb subtype family has a putative furin cleavage site. This subtyping tool might be useful in characterizing Cryptosporidium skunk genotype in clinical and environmental samples.
Project description:Cryptosporidium chipmunk genotype I is an emerging zoonotic pathogen in humans. The lack of subtyping tools makes it impossible to determine the role of zoonotic transmission in epidemiology. To identify potential subtyping markers, we sequenced the genome of a human chipmunk genotype I isolate. Altogether, 9,509,783 bp of assembled sequences in 853 contigs were obtained, with an N50 of 117,886 bp and >200-fold coverage. Based on the whole-genome sequence data, two genetic markers encoding the 60-kDa glycoprotein (gp60) and a mucin protein (ortholog of cgd1_470) were selected for the development of a subtyping tool. The tool was used for characterizing chipmunk genotype I in 25 human specimens from four U.S. states and Sweden, one specimen each from an eastern gray squirrel, a chipmunk, and a deer mouse, and 4 water samples from New York. At the gp60 locus, although different subtypes were seen among the animals, water, and humans, the 15 subtypes identified differed mostly in the numbers of trinucleotide repeats (TCA, TCG, or TCT) in the serine repeat region, with only two single nucleotide polymorphisms in the nonrepeat region. Some geographic differences were found in the subtype distribution of chipmunk genotype I from humans. In contrast, only two subtypes were found at the mucin locus, which differed from each other in the numbers of a 30-bp minisatellite repeat. Thus, Cryptosporidium chipmunk genotype I isolates from humans and wildlife are genetically similar, and zoonotic transmission might play a potential role in human infections.
Project description:Three strains of a novel Bartonella species (Bartonella tamiae) were isolated from human patients from Thailand. Sequence analysis of six chromosomal regions (16S rRNA, gltA, groEL, ftsZ, rpoB, and the intergenic spacer region) and phenotypical analysis supported the similarity of the three strains and placed them within the genus Bartonella separately from previously described species.
Project description:Hepatitis E is an emerging viral disease that is the leading cause of viral hepatitis in the world. The vast majority of hepatitis E cases in developed countries are caused by zoonotic genotypes 3 and 4 of hepatitis E virus (HEV) for which pig and wild boar and to lesser extent rabbits are the main reservoir. According to recent reports rabbits are a source of human HEV infection and highlight the risk of zoonotic foodborne transmission. Here we report the molecular analysis of a novel HEV strain identified in a rabbit during a countrywide surveillance of rabbits and hares in Germany, 2016. The analysis of the complete genome reveals characteristics of a putative novel recombinant subtype of the species Orthohepevirus A within the clade of genotype 3 but not closely related to any known subtypes. Importantly, the genome of this strain possesses a nucleotide exchange in the overlapping region of open reading frames ORF2/ORF3 interfering with a broadly applied diagnostic real-time RT-PCR. In conclusion, a new type of HEV strain was identified in a German rabbit with atypical and novel sequence characteristics.
Project description:This report describes a case of cryptosporidiosis from an immunocompetent patient from Perth, Western Australia, suffering from diarrhea and a spectrum of other symptoms. Molecular identification revealed that this patient was infected with three Cryptosporidium species-Cryptosporidium meleagridis, the Cryptosporidium mink genotype, and an unknown Cryptosporidium species.
Project description:Viral metagenomic analysis was used to identify a previously uncharacterized parvovirus species, "HBoV2," whose closest phylogenetic relative is the human bocavirus (HBoV). HBoV2 has a genomic organization identical to that of HBoV but has only 78%, 67%, and 80% identity, respectively, with the latter's NS1, NP1, and VP1/VP2 proteins. The study used polymerase chain reaction to detect HBoV2 sequences in 5 of 98 stool samples from Pakistani children and in 3 of 699 stool samples from Edinburgh. Nearly-full-length genome sequencing revealed the presence of 3 HBoV2 genotypes and evidence of recombination between genotypes. Further studies are necessary to identify anatomical sites of HBoV2 replication and potential associations with clinical symptoms or disease.
Project description:Cryptosporidium muris, predominantly a rodent species of Cryptosporidium, is not normally considered a human pathogen. Recently, isolated human infections have been reported from Indonesia, Thailand, France, and Kenya. We report the first case of C. muris in a human in the Western Hemisphere. This species may be an emerging zoonotic pathogen capable of infecting humans.
Project description:We identified an unusual subtype of a Cryptosporidium sp. horse genotype as the cause of cryptosporidiosis in a 13-year-old girl in Poland who was undergoing immunosuppressive treatment for juvenile rheumatoid arthritis and Crohn's disease. The same subtype was identified in a horse the girl had ridden.
Project description:The fungal pathogen Candida glabrata has emerged as a major health threat since it readily acquires resistance to multiple drug classes, including triazoles and/or echinocandins. Thus far, cellular mechanisms promoting the emergence of resistance to multiple drug classes have not been described in this organism. Here we demonstrate that a mutator phenotype caused by a mismatch repair defect is prevalent in C. glabrata clinical isolates. Strains carrying alterations in mismatch repair gene MSH2 exhibit a higher propensity to breakthrough antifungal treatment in vitro and in mouse models of colonization, and are recovered at a high rate (55% of all C. glabrata recovered) from patients. This genetic mechanism promotes the acquisition of resistance to multiple antifungals, at least partially explaining the elevated rates of triazole and multi-drug resistance associated with C. glabrata. We anticipate that identifying MSH2 defects in infecting strains may influence the management of patients on antifungal drug therapy.