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Our data suggest that for preventing tuberculosis in HIV-infected patients, a daily 2-month regimen of rifampin and pyrazinamide is similar in safety and efficacy to a daily 12-month regimen of isoniazid. This shorter regimen offers practical advantages to both patients and tuberculosis control programs.

Rationale: Treatment of latent tuberculosis (TB) infection with weekly rifapentine and isoniazid is a potentially effective alternative to current therapies. Objectives: To compare the efficacy of weekly rifapentine/isoniazid to daily rifampin/pyrazinamide in preventing TB in household contacts of patients with pulmonary TB in Brazil. Methods: Contacts of patients with TB were randomized to rifapentine 900 mg/isoniazid 900 mg once weekly for 12 wk or rifampin 450-600 mg/pyrazinamide 750-1,500 mg daily for 8 wk and followed for at least 2 yr. Measurements: TB rates, adverse events, and adherence to therapy. Main Results: A total of 399 household contacts were enrolled, 206 in the rifapentine/isoniazid arm and 193 in the rifampin/pyrazinamide arm. The median age was 34 yr, median weight was 63 kg, 60% of participants were female, and only one patient was HIV infected. Rifapentine/isoniazid was well tolerated, but the trial was halted by the investigators before completion because of unanticipated hepatotoxicity in the rifampin/pyrazinamide arm. Twenty of 193 participants (10%) receiving rifampin/pyrazinamide experienced grade 3 or 4 hepatotoxicity, compared with 2 of 206 participants (1%) on rifapentine/isoniazid (p Ͻ 0.001). There were no hospitalizations or deaths due to hepatotoxicity, and all participants' liver enzyme levels returned to normal during follow-up. During followup, four cases of active TB developed, three in the rifapentine/ isoniazid group and one in the rifampin/pyrazinamide group (1.46 vs. 0.52%; difference, 0.94%; 95% confidence interval, Ϫ1.6 to 3.7%). Conclusions: Rifapentine/isoniazid was better tolerated than rifampin/ pyrazinamide and was associated with good protection against TB. Rifapentine/isoniazid weekly for 12 wk is likely a promising therapy for latent TB infection.Keywords: controlled clinical trial; latent tuberculosis; pyrazinamide; rifampin; rifapentine Treatment of latent Mycobacterium tuberculosis infection is an important component of tuberculosis (TB) control (1, 2) In Western countries, targeted testing and treatment of latently infected individuals is recommended for those at increased risk of developing active TB, including contacts of infectious cases, individuals with HIV infection and other conditions that reduce host resistance to TB, and immigrants from endemic areas, among others (1). Chemoprophylaxis of high-risk patients using isonia- zid (INH) reduces the risk of developing active disease by 60 to 90%, and is the standard of care throughout the world (3). Although INH preventive therapy is highly efficacious and inexpensive, its use may be limited by toxicity and poor adherence with the long duration of treatment required for patients with no symptoms. Consequently, the development of alternative, shorter regimens to treat latent TB infection has become a priority (4).Rifamycin antibiotics have greater potency against the dormant and semidormant organisms that characterize latent TB infection than INH alone, and may be effective when given for shorter duration...

The tools and strategies of syndromic surveillance, say the authors, hold promise for improving public health security in developing countries.

No abstract

A whole-blood interferon-gamma release assay (IGRA) is being evaluated for its potential to replace the tuberculin skin test (TST) for detecting Mycobacterium tuberculosis infection. To test the assay in a population in which tuberculosis is highly endemic and in another population that is representative of an urban United States population, 253 volunteers from Ethiopia and 175 volunteers from Baltimore were studied for responsiveness on IGRA compared with a simultaneously performed TST. The agreement between the 2 tests, beyond that due to chance, was 68% among subjects from Baltimore and only 35% among those from Ethiopia. IGRA had a sensitivity of 71%, compared with 95% sensitivity for the TST, among 21 subjects who had undergone treatment for culture-confirmed tuberculosis. The specificity was 85% for IGRA and 96% for TST among 52 subjects with no known history of exposure to tuberculosis. In its current form, with purified protein derivative used as the stimulation antigen, the IGRA was found to perform poorly in comparison to the TST in diagnosing M. tuberculosis infection.

Infection with the human immunodeficiency virus type 1 (HIV-1) results in decreased cell-mediated immunity, which includes decreased delayed hypersensitivity to skin test antigens. HIV-1 seropositivity and skin test reactivity to purified protein derivative (PPD) were determined among 2042 healthy Haitian adults with normal chest radiographs. Among HIV-1-seropositive individuals, 52.3% (146/279) had PPD reactions greater than or equal to 10 mm compared with 67.2% (1184/1763) of the seronegative adults (P less than .001). However, the percentage of HIV-1-seropositive individuals with PPD reactions greater than or equal to 5 mm was similar to the percentage of seronegative adults with PPD reactions greater than or equal to 10 mm (180/279 [64.5%] vs. 1184/1763 [67.2%]). Assuming that the rate of prior infection with Mycobacterium tuberculosis was similar for HIV-1-seronegative and -seropositive populations, these data provide support for the recent recommendations to use induration of greater than or equal to 5 mm as evidence of past infection with M. tuberculosis in HIV-1 seropositive adults.

Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES) is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations.