What Can Genetic Relatedness Tell Us About Risk Factors for Tuberculosis Transmission?

ABSTRACTExtended-spectrum cephalosporin resistance (ESC-R) in Escherichia coli and Klebsiella pneumoniae is a healthcare threat; high gastrointestinal carriage rates are reported from South-east Asia. Colonisation prevalence data in Cambodia are lacking. We determined gastrointestinal colonisation prevalence of ESC-resistant E. coli (ESC-R-EC) and K. pneumoniae (ESC-R-KP) in Cambodian children/adolescents and associated risk factors; characterised relevant resistance genes, their genetic contexts, and the genetic relatedness of ESC-R strains using whole genome sequencing (WGS). Faeces and questionnaire data were obtained from individuals <16 years in northwestern Cambodia, 2012. WGS of cultured ESC-R-EC/KP was performed (Illumina). Maximum likelihood phylogenies were used to characterise relatedness of isolates; ESC-R-associated resistance genes and their genetic contexts were identified from de novo assemblies using BLASTn and automated/manual annotation. 82/148 (55%) of children/adolescents were ESC-R-EC/KP colonised; 12/148 (8%) were co-colonised with both species. Independent risk factors for colonisation were hospitalisation (OR: 3.12, 95%, CI [1.52-6.38]) and intestinal parasites (OR: 3.11 [1.29-7.51]); school attendance conferred decreased risk (OR: 0.44 [0.21-0.92]. ESC-R strains were diverse; the commonest ESC-R mechanisms were blaCTX-M 1 and 9 sub-family variants. Structures flanking these genes were highly variable, and for blaCTX-M-15,-55and-27, frequently involved IS26. Chromosomal blaCTX-M integration was common in E. coli. Gastrointestinal ESC-R-EC/KP colonisation is widespread in Cambodian children/adolescents; hospital admission and intestinal parasites are independent risk factors. The genetic contexts of blaCTX-M are highly mosaic, consistent with rapid horizontal exchange. Chromosomal integration of blaCTX-M may result in stable propagation in these community-associated pathogens.

Download Full-text

Nosocomial Tuberculosis Transmission from 2006 to 2018 in Beijing Chest Hospital, China

10.21203/rs.3.rs-18459/v3 ◽

2020 ◽

Author(s):

Zhongyao Xie ◽

Ning Zhou ◽

Yuqing Chi ◽

Guofang Huang ◽

Jingping Wang ◽

...

Keyword(s):

Risk Factors ◽

Mechanical Ventilation ◽

Natural Ventilation ◽

Cox Regression ◽

Protective Effects ◽

Cox Regression Analysis ◽

Tuberculosis Transmission ◽

Regression Correlation ◽

Ventilation Systems

Abstract Introduction: Strong evidence is lacking to support effectiveness of currently implemented tuberculosis infection prevention control (TB-IPC) measures for preventing nosocomial tuberculosis (TB) transmission. This 13-year analysis is the longest follow-up investigation to date to identify risk factors underlying nosocomial TB transmission. Methods: We monitored all staff of Beijing Chest Hospital each year from 2006 to 2018. Age, gender, duration, department, education, income, respirator, ultraviolet, and ventilation were chosen as variables. Univariate cox regression, correlation analysis, and multivariate cox regression were analyzed sequentially.Results: Using multivariable cox regression analysis, variables of income, ultraviolet germicidal irradiation (UVGI), natural ventilation and mechanical ventilation conferred significant protective effects, with odds ratios (ORs) of 0.499, 0.058, 0.003, and 0.015, respectively (P<0.05). Medical N95 respirator conferred an excellent protective effect, with an associated TB infection rate of 0%. Notably, inadequately maintained mechanical ventilation systems were less protective than natural ventilation systems.Conclusions: UVGI, adequate ventilation, and use of medical N95 respirator may be risk factors of nosocomial TB transmission.

Download Full-text

Antibiotic Usage and Risk of Colonization and Infection with Antibiotic-Resistant Bacteria: a Hospital Population-Based Study

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00431-09 ◽

2009 ◽

Vol 53 (10) ◽

pp. 4264-4269 ◽

Cited By ~ 82

Author(s):

Evelina Tacconelli ◽

Giulia De Angelis ◽

Maria Adriana Cataldo ◽

Elisabetta Mantengoli ◽

Teresa Spanu ◽

...

Keyword(s):

Risk Factors ◽

Genetic Relatedness ◽

Antibiotic Use ◽

Population Based ◽

Resistant Bacteria ◽

Diabetic Patients ◽

Antibiotic Resistant Bacteria ◽

Multicenter Cohort Study ◽

Antibiotic Resistant ◽

Before And After

ABSTRACT Accurate assessment of risk factors for nosocomial acquisition of colonization by antibiotic-resistant bacteria (ARB) is often confounded by scarce data on antibiotic use. A 12-month, nested, multicenter cohort study was conducted. Target ARB were methicillin (meticillin)-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and ciprofloxacin-resistant Pseudomonas aeruginosa (CR-PA). Nares and rectal swabs were obtained before and after starting antibiotics. Pulsed-field gel electrophoresis was done to define genetic relatedness of the strains. Primary outcomes were (i) the mean time, in days, for acquisition of target ARB colonization in patients previously not colonized; (ii) the rate of acquisition per 1,000 antibiotic-days according to different classes of antibiotics; (iii) the rate of infection caused by the same bacteria as those previously isolated in screening samples; and (iv) the risk factors for ARB acquisition. In total, 6,245 swabs from 864 inpatients were processed. The rate of acquisition was 3%, 2%, and 1% for MRSA, VRE, and CR-PA, respectively. The rate of acquisition of ARB per 1,000 antibiotic-days was 14 for carbapenems, 9 for glycopeptides, and 6 for broad-spectrum cephalosporins and quinolones. The highest rates of acquisition were observed for carbapenems in dialyzed and diabetic patients. Four risk factors were independently associated with acquisition of target ARB: use of carbapenems, age of >70 years, hospitalization for >16 days, and human immunodeficiency virus infection. During the 30-day follow-up, 4 among 42 patients newly colonized by ARB (9%) suffered from an infection due to the same bacteria as those isolated in a previous screening sample. Colonizing and infecting strains from single patients were genotypically identical. Identifying ARB colonization early during antibiotic therapy could target a high-risk hospitalized population that may benefit from intervention to decrease the risk of subsequent nosocomial infections.

Download Full-text

RFLP patterns and risk factors for recent tuberculosis transmission among hospitalized tuberculosis patients in Rio de Janeiro, Brazil

Transactions of the Royal Society of Tropical Medicine and Hygiene ◽

10.1016/s0035-9203(00)90317-1 ◽

2000 ◽

Vol 94 (3) ◽

pp. 271-275 ◽

Cited By ~ 16

Author(s):

F.C.O. Fandinho ◽

A.L. Kritski ◽

C. Hofer ◽

H. Conde ◽

R.M.C. Ferreira ◽

...

Keyword(s):

Risk Factors ◽

Rio De Janeiro ◽

Tuberculosis Patients ◽

Tuberculosis Transmission

Download Full-text

Nosocomial tuberculosis transmission from 2006 to 2018 in Beijing Chest Hospital, China

Antimicrobial Resistance and Infection Control ◽

10.1186/s13756-020-00831-5 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Zhongyao Xie ◽

Ning Zhou ◽

Yuqing Chi ◽

Guofang Huang ◽

Jingping Wang ◽

...

Keyword(s):

Risk Factors ◽

Mechanical Ventilation ◽

Natural Ventilation ◽

Cox Regression ◽

Protective Effects ◽

Cox Regression Analysis ◽

Tuberculosis Transmission ◽

Regression Correlation ◽

Ventilation Systems

Abstract Introduction Strong evidence is lacking to support effectiveness of currently implemented tuberculosis infection prevention control (TB-IPC) measures for preventing nosocomial tuberculosis (TB) transmission. This 13-year analysis is the longest follow-up investigation to date to identify risk factors underlying nosocomial TB transmission. Methods We monitored all staff of Beijing Chest Hospital each year from 2006 to 2018. Age, gender, duration, department, education, income, respirator, ultraviolet, and ventilation were chosen as variables. Univariate cox regression, correlation analysis, and multivariate cox regression were analyzed sequentially. Results Using multivariable cox regression analysis, variables of income, ultraviolet germicidal irradiation (UVGI), natural ventilation and mechanical ventilation conferred significant protective effects, with odds ratios of 0.499, 0.058, 0.003, and 0.015, respectively (P < 0.05). Medical N95 respirator conferred an excellent protective effect, with an associated TB infection rate of 0%. Notably, inadequately maintained mechanical ventilation systems were less protective than natural ventilation systems. Conclusion UVGI, adequate ventilation, and use of medical N95 respirator may be risk factors of nosocomial TB transmission.

Download Full-text

Use of genotyping based clustering to quantify recent tuberculosis transmission in Guadeloupe during a seven years period: analysis of risk factors and access to health care

BMC Infectious Diseases ◽

10.1186/1471-2334-13-364 ◽

2013 ◽

Vol 13 (1) ◽

Cited By ~ 8

Author(s):

Séverine Ferdinand ◽

Julie Millet ◽

Annick Accipe ◽

Sylvie Cassadou ◽

Pascal Chaud ◽

...

Keyword(s):

Risk Factors ◽

Health Care ◽

Access To Health Care ◽

Period Analysis ◽

Tuberculosis Transmission ◽

Access To Health

Download Full-text

Community-Acquired Methicillin-Resistant Staphylococcus aureus: An Emerging Pathogen

Infection Control and Hospital Epidemiology ◽

10.1086/502231 ◽

2003 ◽

Vol 24 (6) ◽

pp. 451-455 ◽

Cited By ~ 111

Author(s):

Battolili Saïd-Salim ◽

Barun Mathema ◽

Barry N. Kreiswirth

Keyword(s):

Risk Factors ◽

New York ◽

Los Angeles ◽

Genetic Relatedness ◽

Protein A ◽

Genetic Characteristics ◽

Type Iv ◽

Severe Infections ◽

Mrsa Strains ◽

Hospital Acquired

AbstractThe prevalence of MRSA in the nosocomial setting has been well studied, and its control remains a challenge for infection control professionals. Complicating this problem is the increasing number of reports on the spread of community-acquired MRSA (CA-MRSA). CA-MRSA strains differ from hospital-acquired MRSA (HA-MRSA) strains in that they are generally susceptible to most antibiotics. These strains share the presence of staphylococcal cassette chromosome mec (SCCwec) type IV in their genomes, are frequently virulent, and predominantly cause skin and soft tissue infections. The genome sequence of the prototypic CA-MRSA strain, MW2, revealed the presence of additional virulence factors not commonly present in other S. aureus strains.We determined the genetic relatedness of 30 geographically diverse CA-MRSA isolates clustered based on SCCmec type IV by sequence analysis of the polymorphic repeat region of the protein A gene (spa typing). These results indicated that most strains shared a common spa type (131), identical to MW2. Because this group tends to infect healthy individuals with no known risk factors for nosocomial acquisition of MRSA, we refer to it as CA-MRSA without risk factors. A second group, CA-MRSA with risk factors, consists of two related genotypes, spa types 1 and 7, which differ by one nucleotide change. These strains have caused severe infections in HIV-positive patients in Los Angeles and New York.Although CA-MRSA strains share genetic determinants, they are not clonal but rather are derived from different genetic backgrounds. The genetic characteristics and the epidemiology of CA-MRSA with and without risk factors are discussed.

Download Full-text

Transmission of tuberculosis and predictors of large clusters within three years in an urban setting in Tokyo, Japan: a population-based molecular epidemiological study

BMJ Open ◽

10.1136/bmjopen-2019-029295 ◽

2019 ◽

Vol 9 (5) ◽

pp. e029295

Author(s):

Kiyohiko Izumi ◽

Yoshiro Murase ◽

Kazuhiro Uchimura ◽

Aya Kaebeta ◽

Keiko Ishihara ◽

...

Keyword(s):

Risk Factors ◽

Homeless People ◽

Urban Setting ◽

Full Time ◽

Foreign Born ◽

Cross Sectional ◽

Tuberculosis Transmission ◽

Large Clusters ◽

Genotype Clustering ◽

Culture Positive

ObjectiveMolecular epidemiology is a promising tool for understanding tuberculosis transmission dynamics but has not been sufficiently utilised in Asian countries including Japan. The aim of this study was to estimate the proportion of TB cases attributable to recent transmission and to identify risk factors of genotype clustering and the development of large clusters within 3 years in an urban setting in Japan.Design and settingLong-term cross-sectional observational study combining the characteristics of patients with culture-positive TB notified in Shinjuku City, Tokyo (2002–2013), with genotype data ofMycobacterium tuberculosis.Primary outcome measureGenotype clustering rate and association between genotype clustering status and explanatory variables.ResultsAmong 1025 cases, 515 were localised within 113 genotype clusters. The overall clustering rate was 39.2%. Significantly higher rates were found in patients aged <40 years (adjusted odds ratio (aOR)=1.73, 95% CI 1.23 to 2.44), native Japanese individuals (aOR=3.90, 95% CI 2.27 to 6.72), full-time workers (aOR=1.63, 95% CI 1.17 to 2.27), part-time/daily workers (aOR=2.20, 95% CI 1.35 to 3.58), individuals receiving public assistance (aOR=1.81, 95% CI 1.15 to 2.84) and homeless people (aOR=1.63, 95% CI 1.02 to 2.62). A significant predictor of large genotype clusters within 3 years was a registration interval ≤2 months between the first two cases in a cluster.ConclusionOur results indicated that a large proportion of patients with culture-positive TB were involved in the recent TB transmission chain. Foreign-born persons still have a limited impact on transmission in the Japanese urban setting. Intensified public health interventions, including the active case finding, need to focus on individuals with socioeconomic risk factors that are significantly associated with tuberculosis transmission and clusters with shorter registration intervals between the first two cases.

Download Full-text