Duration of Exposure Among Close Contacts of Patients With Infectious Tuberculosis and Risk of Latent Tuberculosis Infection.

Background: Predictors of latent tuberculosis infection (LTBI) among close contacts of persons with infectious tuberculosis (TB) are incompletely understood, particularly the number of exposure hours.

Methods: We prospectively enrolled adult patients with culture-confirmed pulmonary TB and their close contacts at 9 health departments in the United States and Canada. Patients with TB were interviewed and close contacts were interviewed and screened for TB and LTBI during contact investigations.

Risk Factors for Tuberculosis and Effect of Preventive Therapy Among Close Contacts of Persons With Infectious Tuberculosis.

Background: Close contacts of persons with pulmonary tuberculosis (TB) have high rates of TB disease.

Methods: We prospectively enrolled TB patients and their close contacts at 9 US/Canadian sites. TB patients and contacts were interviewed to identify index patient, contact, and exposure risk factors for TB.

Risk and Timing of Tuberculosis Among Close Contacts of Persons with Infectious Tuberculosis.

Background: The risk and timing of tuberculosis among recently exposed close contacts of patients with infectious tuberculosis are not well established.

Methods: We prospectively enrolled patients ≥15 years of age with culture-confirmed pulmonary tuberculosis and their close contacts at 9 health departments in the United States and Canada. Close contacts were screened and cross-matched with tuberculosis registries to identify those who developed tuberculosis.

Profiling T cell activation using single-molecule fluorescence in situ hybridization and flow cytometry.

Flow cytometric characterization of Ag-specific T cells typically relies on detection of protein analytes. Shifting the analysis to detection of RNA would provide several significant advantages, which we illustrate by developing a new host immunity-based platform for detection of infections. Cytokine mRNAs synthesized in response to ex vivo stimulation with pathogen-specific Ags are detected in T cells with single-molecule fluorescence in situ hybridization followed by flow cytometry.

Acquired rifamycin resistance with twice-weekly treatment of HIV-related tuberculosis.

Rationale: Rifabutin was recommended in place of rifampin during treatment of HIV-related tuberculosis (TB) to facilitate concomitant potent antiretroviral therapy, but this approach has not been evaluated in a prospective study.

Objective: To evaluate the activity of intermittent rifabutin-based therapy.

Methods: Patients with culture-confirmed TB were treated under direct supervision with 2 mo of rifabutin, isoniazid, pyrazinamide, and ethambutol (given daily, thrice-weekly, or twice-weekly per the local tuberculosis control program), followed by 4 mo of twice-weekly rifabutin plus isoniazid.

Rethinking the socioeconomics and geography of tuberculosis among foreign-born residents of New Jersey, 1994-1999.

Objectives: This study investigated the socioeconomic profile of foreign-born tuberculosis patients in New Jersey.

Methods: Foreign- and US-born tuberculosis patients in 1994-1999 were compared using various measures of socioeconomic status.

Results: Out of 4295 tuberculosis patients, 2005 (47%) were foreign-born.

Treatment of latent tuberculosis infection in contacts of new tuberculosis cases in the United States.

Background: Few data are available describing treatment completion rates among recently infected contacts of tuberculosis (TB) cases, a group at high risk for development of active TB.

Methods: Health department records were reviewed for all contacts of 360 culture-positive pulmonary TB cases reported from five health departments in the United States in 1996.

Results: Of 2,267 contacts who completed screening, 630 (28%) had newly documented positive skin tests (121 with skin test conversion).

Evaluation of investigations conducted to detect and prevent transmission of tuberculosis.

Context: Contact investigations are routinely conducted by health departments throughout the United States for all cases of active pulmonary tuberculosis (TB) to identify secondary cases of active TB and latent TB infection and to initiate therapy as needed in these contacts. Little is known about the actual procedures followed, or the results.

Objectives: To evaluate contact investigations conducted by US health departments and the outcomes of these investigations.

Identification and evolution of an IS6110 low-copy-number Mycobacterium tuberculosis cluster.

A cohort of 56 patients infected with related strains of Mycobacterium tuberculosis, the S75 group, was identified in a New Jersey population-based study of all isolates with a low number of copies of the insertion element IS6110. Genotyping was combined with surveillance data to identify the S75 group and to elucidate its recent evolution. The S75 group had similar demographic and geographic characteristics.