RESUMEN
SETTING: Tuberculosis (TB) has decreased substantially in New York City (NYC), but progress has slowed in recent years. Continued declines will require novel approaches tailored to foreign-born populations. OBJECTIVE: To describe TB epidemiology among the Mexico-born population of NYC to inform interventions in this community. DESIGN: The study included NYC patients with TB disease identified from 2001 to 2014. Incidence rates were compared by country of birth groupings. Demographic and patient characteristics were analyzed for all Mexico-born TB patients. Patients were compared by Mycobacterium bovis vs. non-M. bovis TB strain. Culture-confirmed patients were compared by genotype clustering status. RESULTS: From 2001 to 2014, 621 Mexico-born TB patients were identified in NYC. TB rates were significantly higher among Mexico-born vs. US-born persons every year. Mexico-born patients had lived in the United States for a median 7 years at diagnosis. The geographic distribution of Mexico-born TB patients was similar to that of the total Mexico-born population. Overall, 71% of patients reported previous employment; 52% of non-M. bovis patients were clustered based on genotyping results. CONCLUSIONS: Our results provide a foundation to inform future interventions in the Mexico-born population. Additional work is needed to explore possible local TB transmission and health care-seeking practices.
Asunto(s)
Mycobacterium bovis/aislamiento & purificación , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Análisis por Conglomerados , Femenino , Genotipo , Humanos , Incidencia , Masculino , México/etnología , Persona de Mediana Edad , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Ciudad de Nueva York/epidemiología , Tuberculosis/microbiología , Adulto JovenRESUMEN
We have determined the complete coding sequences of six dengue-1 (DEN-1) viruses isolated from Paraguay and Argentina in 2000 from patients with dengue fever. Sequences of strains 259par00, 280par00, 295arg00, 297arg00 and 301arg00 can encode a polyprotein of 3392 amino acids. Strain 293arg00 circulated as a "wild type+deletion mutant" quasispecies, with a subpopulation characterized by a 3-nucleotide deletion in the NS4A region. This variant, which would encode a three amino acid change in the NS4A protein, was found as a minority population in one additional partially-sequenced isolate from the same outbreak. These six South American strains group into two different clades of the "American-African" DEN-1 genotype-one clade is most closely related to strains isolated from Brazil in 1997, the other to a Peruvian strain isolated in 1991 for which only partial sequence information is available. DEN-1 viruses isolated worldwide comprise at least four different genotypes according to previously defined classification criteria.
Asunto(s)
Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Dengue/virología , Brotes de Enfermedades , Secuencia de Aminoácidos , Argentina/epidemiología , Secuencia de Bases , Dengue/epidemiología , Virus del Dengue/clasificación , Genoma Viral , Humanos , Datos de Secuencia Molecular , Paraguay/epidemiología , Filogenia , Análisis de Secuencia de ADNRESUMEN
We sequenced the Capsid-pre Membrane (C/prM) and the Envelope-Nonstructural protein 1 (E/NS1) regions of 24 recent isolates of dengue-1 (DEN-1) from South America. This included 12 Argentinean and 11 Paraguayan DEN-1 strains isolated in 2000 plus a Paraguayan strain isolated in 1988. These sequences were compared with published sequences of DEN-1 isolated worldwide to determine the origin of these isolates. Pairwise comparisons of strains from Paraguay and Argentina revealed a nucleotide divergence of 0-5% in the E/NS1 region and 0-3% in the C/prM region. Our results showed that these viruses belong to the same genotype, but can be separated into two clades. Interestingly, both clades circulated simultaneously in the same geographic area during the 2000 outbreaks. Amino acid differences were found between both clades in the C/prM region at position 100 (Lys vs. Arg) and in the E/NS1 region at positions 722 (Ala vs. Thr). Although the geographic movement of DEN-1 virus can not be unequivocally traced from the genetic relationship determined here, our results suggest that the recent epidemics in Argentina and Paraguay were due to the re-emergence of a previously circulating strain, or to the virus circulating unnoticed, rather than to the introduction of a new genotype.
Asunto(s)
Virus del Dengue/clasificación , Secuencia de Aminoácidos , Argentina , Virus del Dengue/genética , Genotipo , Datos de Secuencia Molecular , Paraguay , Filogenia , Proteínas del Envoltorio Viral/química , Proteínas no Estructurales Virales/químicaRESUMEN
The 5' nontranslated region (5'NTR) and nonstructural region nucleotide sequences of nine enzootic Venezuelan equine encephalitis (VEE) virus strains were determined, thus completing the genomic RNA sequences of all prototype strains. The full-length genomes, representing VEE virus antigenic subtypes I-VI, range in size from 11.3 to 11.5 kilobases, with 48-53% overall G+C contents. Size disparities result from subtype-related differences in the number and length of direct repeats in the C-terminal nonstructural protein 3 (nsP3) domain coding sequence and the 3'NTR, while G+C content disparities are attributable to strain-specific variations in base composition at the wobble position of the polyprotein codons. Highly-conserved protein components and one nonconserved protein domain constitute the VEE virus replicase polyproteins. Approximately 80% of deduced nsP1 and nsP4 amino acid residues are invariant, compared to less than 20% of C-terminal nsP3 domain residues. In two enzootic strains, C-terminal nsP3 domain sequences degenerate into little more than repetitive serine-rich blocks. Nonstructural region sequence information drawn from a cross-section of VEE virus subtypes clarifies features of alphavirus conserved sequence elements and proteinase recognition signals. As well, whole-genome comparative analysis supports the reclassification of VEE subtype-variety IF and subtype II viruses.