Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
1.
Emerg Infect Dis ; 30(1): 116-124, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38146997

ABSTRACT

We conducted an epidemiologic assessment of disease distribution by race/ethnicity to identify subpopulation-specific drivers of tuberculosis (TB). We used detailed racial/ethnic categorizations for the 932 TB cases diagnosed in Arkansas, USA, during 2010-2021. After adjusting for age and sex, racial/ethnic disparities persisted; the Native Hawaiian/Pacific Islander (NHPI) group had the highest risk for TB (risk ratio 173.6, 95% CI 140.6-214.2) compared with the non-Hispanic White group, followed by Asian, Hispanic, and non-Hispanic Black. Notable racial/ethnic disparities existed across all age groups; NHPI persons 0-14 years of age were at a particularly increased risk for TB (risk ratio 888, 95% CI 403-1,962). The risks for sputum smear-positive pulmonary TB and extrapulmonary TB were both significantly higher for racial/ethnic minority groups. Our findings suggest that TB control in Arkansas can benefit from a targeted focus on subpopulations at increased risk for TB.


Subject(s)
Ethnicity , Tuberculosis , Humans , Arkansas/epidemiology , Incidence , Minority Groups , Tuberculosis/epidemiology
2.
Lepr Rev ; 87(1): 109-12, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27255065

ABSTRACT

The cross-immunity between tuberculosis and leprosy is unknown. The aim of this pilot study was to evaluate the occurrence of Mycobacterium tuberculosis and M. leprae infection in Marshallese adult volunteers in Springdale, Arkansas, U.S.A., a population that experiences high rates of leprosy and tuberculosis. We used immunodiagnostic testing for tuberculosis and leprosy infection and found significant prevalence of latent tuberculosis infection (19.0%), and asymptomatic Mycobacterium leprae infection (22.2%). We found a negative association between presence of antibodies to Mycobacterium leprae and a positive interferon-γ release assay for Mycobacterium tuberculosis infection, prevalence odds ratio = 0.1 (95% CI = 0.0, 0.9). Although these findings require confirmation on a larger scale, they are supportive of the existence of cross-immunity.


Subject(s)
Leprosy/epidemiology , Tuberculosis/epidemiology , Adolescent , Adult , Aged , Arkansas/epidemiology , Humans , Leprosy/ethnology , Middle Aged , Pilot Projects , Tuberculosis/ethnology , Young Adult
3.
J Theor Biol ; 380: 238-46, 2015 Sep 07.
Article in English | MEDLINE | ID: mdl-26051196

ABSTRACT

Comprehensive assessment of the effectiveness of contact investigations for tuberculosis (TB) control is still lacking. In this study, we use a computational model, calibrated against notification data from Arkansas during the period 2001-2011, that reproduces independent data on key features of TB transmission and epidemiology. The model estimates that the Arkansas contact investigations program has avoided 18.6% (12.1-25.9%) of TB cases and 23.7% (16.4-30.6%) of TB deaths that would have occurred during 2001-2014 if passive diagnosis alone were implemented. If contacts of sputum smear-negative cases had not been included in the program, the percentage reduction would have been remarkably lower. In addition, we predict that achieving national targets for performance indicators of contact investigation programs has strong potential to further reduce TB transmission and burden. However, contact investigations are expected to have limited effectiveness on avoiding reactivation cases of latent infections over the next 60 years.


Subject(s)
Contact Tracing , Tuberculosis/prevention & control , Arkansas/epidemiology , Humans , Models, Theoretical , Prevalence , Tuberculosis/epidemiology
4.
Circ Cardiovasc Qual Outcomes ; 6(6): 668-73, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24150043

ABSTRACT

BACKGROUND: The excess stroke mortality in the southeastern states of the United States (stroke-belt states) is well known; however, the factors associated with this pattern have not been fully elucidated. We measured the contribution of several demographic factors by analyzing stroke mortality data (2005-2009) at the census block group (BG) level in the state of Arkansas. METHODS AND RESULTS: Census BGs were used as proxies for neighborhoods. BGs were stratified using 5 census measures: poverty (percent of population below federal poverty level), population density (population per square mile), education (percent of population aged >25 years who did not graduate from high school), population mobility (percent of population who resided at the same address 1 year ago), and the percent of non-Hispanic blacks (percent of population that is black). Generalized additive models were used to estimate the variation in stroke mortality among BGs and to assess the impact of different demographic variables. From 2005 to 2009, there were 8930 stroke deaths in Arkansas. There was considerable variation in the relative risk even between adjacent BGs within a single county. The geographically weighted regression analyses indicated that 4.5% to 9% of deviance in stroke mortality among BGs could be explained by poverty, education, population density, and population mobility. Race/ethnicity (non-Hispanic blacks) explains <2% of the deviance in stroke mortality among BGs. CONCLUSIONS: Our study shows that primordial risk factors such as poverty and education drive disparities in stroke mortality among neighborhoods in Arkansas.


Subject(s)
Black or African American , Demography , Poverty , Residence Characteristics , Stroke/epidemiology , Adult , Arkansas , Female , Humans , Male , Middle Aged , Models, Statistical , Risk Factors , Stroke/mortality , Survival Analysis
5.
Tuberculosis (Edinb) ; 91(3): 244-9, 2011 May.
Article in English | MEDLINE | ID: mdl-21367661

ABSTRACT

It was reported previously that the major fraction of the recent decrease of tuberculosis incident cases in Arkansas had been due to a decrease in the reactivated infections. Preventing transmission of Mycobacterium tuberculosis is the key to a continued decline in tuberculosis cases. In this study, we integrated epidemiological data analysis and comparative genomics to identify host and microbial factors important to tuberculosis transmission. A significantly higher proportion of cases in large clusters (containing >10 cases) were non-Hispanic black, homeless, less than 65 years old, male sex, smear-positive sputum, excessive use of alcohol, and HIV sero-positive, compared to cases in small clusters (containing 2-5 cases) diagnosed within one year. However, being non-Hispanic black and homeless within the past year were the only two host characteristics that were identified as independent risk factors for being in large clusters. This finding suggests that social behavioral factors have a more important role in transmission of tuberculosis than does the infectiousness of the source. Comparing the genomic content of one of the large cluster strains to that of a non-clustered strain from the same community identified 25 genes that differed between the two strains, potentially contributing to the observed differences in transmission.


Subject(s)
Host-Pathogen Interactions , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/transmission , Black or African American/statistics & numerical data , Aged , Arkansas/epidemiology , Cluster Analysis , Female , Genetic Variation , Genotype , HIV Seropositivity/epidemiology , Hispanic or Latino/statistics & numerical data , Ill-Housed Persons/statistics & numerical data , Humans , Interdisciplinary Communication , Male , Middle Aged , Molecular Epidemiology , Mycobacterium tuberculosis/classification , Risk Factors , Sputum/microbiology , Tuberculosis/epidemiology
6.
J Ark Med Soc ; 105(12): 283-4, 286, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19606641

ABSTRACT

The incidence of invasive female breast cancer declined 6.7% in the United States from 2002 to 2003 following a nationwide decrease in the use of hormone replacement therapy that began in 2002. We used data from the Arkansas Central Cancer Registry to look for similar changes in the incidence of female breast cancer in Arkansas. There was a 9.3% decline in the incidence of invasive female breast cancer in Arkansas in 2003, and the decline continued through 2005. The decline was significantly higher (p<0.05) among invasive cancers, particularly among women ages 50 and older and for those having an estrogen-receptor positive tumor.


Subject(s)
Breast Neoplasms/epidemiology , Age Distribution , Aged , Aged, 80 and over , Arkansas/epidemiology , Female , Humans , Incidence , Middle Aged , Registries/statistics & numerical data , SEER Program/statistics & numerical data
7.
Tuberculosis (Edinb) ; 89(2): 114-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19027362

ABSTRACT

Mycobacterium tuberculosis lipases, a diverse class of enzymes involved in lipid metabolism, may have an important role in tuberculosis (TB) pathogenesis. We explored the association of large sequence polymorphism (LSP) in one of the M. tuberculosis lipase-encoding genes, lipR (Rv3084), with patient characteristics using a population-based sample of clinical isolates to elucidate the potential role of lipR in TB pathogenesis. LSP in lipR was found in 104 (15.6%) of 665 isolates, of which 96% belonged to principal genetic group 3. When linkage by molecular type and epidemiologic evidence were compared, molecularly clustered cases infected with a lipR LSP isolate were more often epidemiologically linked than clustered cases infected with a lipR wild-type isolate. Further epidemiologic and functional studies are necessary to determine if the association between this lipR LSP and recent transmission we identified in this population reflects a functional role of lipR in TB transmission and pathogenesis or other unidentified mechanisms.


Subject(s)
Bacterial Proteins/genetics , Esterases/genetics , Hydrolases/genetics , Mycobacterium tuberculosis/pathogenicity , Tuberculosis/transmission , Adolescent , Adult , Aged , Aged, 80 and over , Arkansas/epidemiology , Child , Child, Preschool , Chromosome Mapping , Cluster Analysis , Female , Genes, Bacterial , Genotype , Humans , Infant , Infant, Newborn , Male , Middle Aged , Mycobacterium tuberculosis/enzymology , Mycobacterium tuberculosis/genetics , Polymorphism, Genetic , Tuberculosis/epidemiology , Tuberculosis/microbiology , Virulence/genetics , Young Adult
8.
Am J Epidemiol ; 166(6): 662-71, 2007 Sep 15.
Article in English | MEDLINE | ID: mdl-17625223

ABSTRACT

Incident cases of tuberculosis may result from a recently acquired Mycobacterium tuberculosis infection or from the reactivation of a latent infection acquired in the remote past. The authors used molecular fingerprinting data to estimate the relative contributions of recent and remotely acquired infection to the yearly incidence of tuberculosis in Arkansas, a state with a largely rural population where the incidence of tuberculosis declined from 7.9 cases per 100,000 population to 4.7 cases per 100,000 between 1997 and 2003. The authors used a time-restricted definition of clustering in addition to the standard definition in order to increase the specificity of the clustering measure for recent transmission. The greatest overall declines were seen in non-Hispanic Blacks (from 13.8 cases per 100,000 in 1997 to 6.5 cases per 100,000 in 2003) and persons aged 65 years or more (from 19.9 cases per 100,000 in 1997 to 8.5 cases per 100,000 in 2003). In both groups, the incidence of nonclustered cases declined more dramatically than the incidence of clustered cases. This suggests that the decline in rates resulted primarily from declining rates of disease due to reactivation of past infections. Declines in the overall incidence of tuberculosis in a population may not necessarily result from declines in active transmission.


Subject(s)
Tuberculosis/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Arkansas/epidemiology , Chi-Square Distribution , Cluster Analysis , DNA Fingerprinting , Female , Genotype , Humans , Incidence , Male , Middle Aged , Mycobacterium tuberculosis/genetics , Poisson Distribution , Polymorphism, Restriction Fragment Length , Population Surveillance , Risk Factors , Rural Population , Tuberculosis/ethnology
9.
Tuberculosis (Edinb) ; 87(4): 338-46, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17475562

ABSTRACT

There is evidence that some members of the Mycobacterium tuberculosis PE PGRS gene subfamily, including PE PGRS33, may have a specific function in M. tuberculosis persistence. The impact of naturally-occurring PE PGRS33 genetic variations on the virulence and transmissibility of clinical M. tuberculosis isolates is not known. We used PCR and DNA sequencing to identify genetic variations in the PE PGRS33 gene in comparison with the sequenced laboratory strain, H37Rv, among 649 isolates from a population-based sample. The PE PGRS33 alleles were placed into two groups, based on the effect of the sequence variations on the PE PGRS33 protein, and their associations with clinical and epidemiological characteristics were assessed using multivariate logistic regression to control for potential confounding of host-related factors. Of the 639 isolates for which sequence data were obtained, 139 (21.8%) had PE PGRS33 alleles that would result in a significant change to the PE PGRS33 protein due to large insertions/deletions or frameshift mutations. These isolates were significantly associated with clustering based on genotype and absence of cavitations in the lungs, compared to isolates having PE PGRS33 alleles that would result in no or minimal change to the PE PGRS33 protein. The association of significant changes to PE PGRS33 with clinical and epidemiological characteristics suggests that PE PGRS33 may have an important role in M. tuberculosis persistence.


Subject(s)
Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Genes, Bacterial/genetics , Membrane Proteins/genetics , Mycobacterium tuberculosis/genetics , Tuberculosis/genetics , Arkansas/epidemiology , Cluster Analysis , Female , Frameshift Mutation , Genetic Variation , Humans , Male , Mycobacterium tuberculosis/pathogenicity , Peptide Mapping , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Sequence Analysis, DNA , Seroepidemiologic Studies , Tuberculosis/epidemiology
10.
Am J Respir Crit Care Med ; 171(12): 1436-42, 2005 Jun 15.
Article in English | MEDLINE | ID: mdl-15805187

ABSTRACT

To identify Mycobacterium tuberculosis virulence factors, we integrated comparative genomics and epidemiologic data analysis to investigate the relationship between certain genomic insertions and deletions in the phospholipase-C gene D (plcD) with the clinical presentation of tuberculosis (TB). Four hundred ninety-six well-characterized M. tuberculosis clinical isolates were studied. Approximately 30% (147) of the isolates had an interruption of the plcD gene. Patients infected with the plcD mutant were twice as likely to have extrathoracic disease as those infected by a strain without an interruption (adjusted odds ratio, 2.19; 95% confidence interval, 1.27, 3.76). When we limited the analysis to the 275 isolates with distinct DNA fingerprint patterns, we observed the same association (adjusted odds ratio, 2.74; 95% confidence interval, 1.35, 5.56). Furthermore, the magnitude of the association appeared to differ with the type of extrathoracic TB. Our findings suggest that the plcD gene of M. tuberculosis is potentially involved in the pathogenesis of TB, and the clinical presentation of the disease may be influenced by the genetic variability of the plcD region.


Subject(s)
Mutation , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/pathogenicity , Tuberculosis/microbiology , Type C Phospholipases/genetics , Adult , Aged , Blotting, Southern , DNA Fingerprinting , Disease Progression , Female , Genes, Bacterial/genetics , Genetic Markers/genetics , Humans , Male , Middle Aged , Polymerase Chain Reaction , Sensitivity and Specificity , Sequence Analysis, DNA , Severity of Illness Index , Tuberculosis/physiopathology , Type C Phospholipases/metabolism
11.
Clin Infect Dis ; 38(2): 199-205, 2004 Jan 15.
Article in English | MEDLINE | ID: mdl-14699451

ABSTRACT

The proportion of extrapulmonary tuberculosis cases in the United States has increased from 16% of tuberculosis cases, in 1991, to 20%, in 2001. To determine associations between the demographic, clinical, and life style characteristics of patients with tuberculosis and the occurrence of extrapulmonary tuberculosis, a retrospective case-control study was conducted. This study included 705 patients with tuberculosis, representing 98% of the culture-proven cases of tuberculosis in Arkansas from 1 January 1996 through 31 December 2000. A comparison between 85 patients with extrapulmonary tuberculosis (case patients) and 620 patients with pulmonary tuberculosis (control patients) showed women (OR, 1.98; 95% CI, 1.25-3.13), non-Hispanic blacks (OR, 2.38; 95% CI, 1.42-3.97), and HIV-positive persons (OR, 4.93; 95% CI, 1.95-12.46) to have a significantly higher risk for extrapulmonary tuberculosis than men, non-Hispanic whites, and HIV-negative persons. This study expands the knowledge base regarding the epidemiology of extrapulmonary tuberculosis and enhances our understanding of the relative contribution of host-related factors to the pathogenesis of tuberculosis.


Subject(s)
Tuberculosis/epidemiology , Adolescent , Adult , Age Distribution , Age Factors , Aged , Case-Control Studies , Child , Child, Preschool , Female , HIV Infections/complications , Humans , Infant , Infant, Newborn , Male , Middle Aged , Retrospective Studies , Risk Factors , Sex Factors , Tuberculosis/ethnology , Tuberculosis/physiopathology
12.
Emerg Infect Dis ; 8(11): 1246-8, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12453349

ABSTRACT

A cluster of tuberculosis cases in a rural community in Arkansas persisted from 1991 to 1999. The cluster had 13 members, 11 linked epidemiologically. Old records identified 24 additional patients for 40 linked cases during a 54-year period. Residents of this neighborhood represent a population at high risk who should be considered for tuberculin testing and treatment for latent tuberculosis infection.


Subject(s)
Mycobacterium tuberculosis/isolation & purification , Rural Population , Tuberculosis/transmission , Adolescent , Aged , Aged, 80 and over , Antitubercular Agents/pharmacology , Arkansas/epidemiology , Child , Child, Preschool , Cluster Analysis , DNA Fingerprinting , Drug Resistance, Multiple, Bacterial , Female , Humans , Infant , Male , Middle Aged , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Risk , Rural Health , Time Factors , Tuberculosis/epidemiology , Tuberculosis/microbiology
13.
Emerg Infect Dis ; 8(11): 1257-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12453352

ABSTRACT

Molecular epidemiologic studies provide evidence of transmission of Mycobacterium tuberculosis within clusters of patients whose isolates share identical IS6110-DNA fingerprint patterns. However, M. tuberculosis transmission among patients whose isolates have similar but not identical DNA fingerprint patterns (i.e., differing by a single band) has not been well documented. We used DNA fingerprinting, combined with conventional epidemiology, to show unsuspected patterns of tuberculosis transmission associated with three public bars in the same city. Among clustered TB cases, DNA fingerprinting analysis of isolates with similar and identical fingerprints helped us discover epidemiologic links missed during routine tuberculosis contact investigations.


Subject(s)
DNA Fingerprinting , Mycobacterium tuberculosis/genetics , Tuberculosis/microbiology , Tuberculosis/transmission , Adult , Arkansas/epidemiology , Cluster Analysis , Contact Tracing , Humans , Molecular Epidemiology , Mycobacterium tuberculosis/classification , Risk Factors , Tuberculosis/epidemiology
14.
J Am Geriatr Soc ; 50(7): 1213-8, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12133015

ABSTRACT

OBJECTIVES: To determine the reason for an increase in tuberculin skin test (TST) conversion in employees in a nursing home and to determine the source case responsible for spread of tuberculosis (TB) in two nursing homes and a hospital in a rural part of Arkansas using molecular and traditional epidemiological methods. DESIGN: TB contact investigation of residents and employees of two nursing homes and a hospital. SETTING: Two nursing homes and a hospital in rural part of Arkansas. PARTICIPANTS: One hundred fifty-seven employees and 117 residents of two nursing homes and 211 employees of a hospital in rural part of Arkansas. MEASUREMENTS: Tuberculin skin test. RESULTS: Analysis of room and work assignments of residents and employees who converted their TSTs in Nursing Home A showed that residents and employees in the same wing as the suspect source case were significantly more likely to have converted their TST than residents and employees in other wings (P = .01). A nurse from the local hospital where the suspected source case had been sent developed a tuberculous cervical abscess, and one employee in Nursing Home A developed pulmonary TB. A visitor to Nursing Home A was diagnosed with culture-positive pulmonary TB 2 years later. Genotyping of the Mycobacterium tuberculosis isolates from the four secondary cases showed identical patterns. CONCLUSION: Molecular and traditional epidemiological studies revealed an outbreak of TB that began in a nursing home and spread to a second nursing home, a local hospital, and the community.


Subject(s)
Disease Outbreaks , Nursing Homes , Occupational Diseases/epidemiology , Tuberculosis/epidemiology , Adult , Aged , Aged, 80 and over , Arkansas/epidemiology , Chi-Square Distribution , Diagnosis, Differential , Female , Genotype , Hospitals, Community , Humans , Male , Middle Aged , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , Occupational Diseases/diagnosis , Tuberculin Test , Tuberculosis/diagnosis , Tuberculosis/transmission
SELECTION OF CITATIONS
SEARCH DETAIL
...