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Mycobacterium intracellulare (MIT) was diagnosed postmortem by culture and supporting histopathology in seven birds from a flock of little blue penguins (Eudyptula minor) at the Henry Doorly Zoo (HDZ). These birds represented 20% of the deaths in the population over a 4 yr period. Clinical signs in affected birds included severe respiratory distress characterized by open-mouth breathing with chronic debilitation. On exam, plaques were noted in the larynx, trachea, and soft tissue of the caudal oropharynx. Index cases were identified on necropsy in two birds on loan to another institution in 2003. Following a case confirmed antemortem at the HDZ, a three-drug protocol of rifampin (15 mg/kg p.o. s.i.d.), ethambutol (15 mg/kg p.o. s.i.d.), and clarithromycin (10 mg/kg p.o. s.i.d.) was started on this bird in 2004 and extended to the entire flock in 2005. Gastric wash, fecal samples, and throat plaques were obtained antemortem on five birds within the flock, selected because of the presence of oral plaques, and tested by culture followed by a polymerase chain reaction assay. MIT was detected in gastric washes from four birds and in throat plaques from all five. Three more birds died during treatment. After the seventh bird died, antimicrobial susceptibility testing performed in July 2007 indicated that the MIT was now resistant to most antibiotics tested, including rifampin and ethambutol. The treatment regimen was changed to minocycline (10 mg/kg p.o. b.i.d.) and clarithromycin (10 mg/kg p.o. s.i.d.). Oral plaques were not seen on monthly rechecks of the flock through November 2008. The proposed mechanism of transmission is exposure to wild birds but the source has not been determined. These cases of avian mycobacteriosis caused by MIT are the first known cases reported in little blue penguins.

A cost analysis of combining a tuberculin skin test (TST) and the QuantiFERON-TB Gold test (QFT-GT)to detect latent tuberculosis in newly hired health care workers was performed. An approximately 50% reduction in the cost of additional care was realized when workers with positive TST results were subsequently screened using the QFT-GT.Tuberculosis (TB) is a leading cause of morbidity and mortality worldwide, with 9 million new cases and 2 million deaths reported in 2006 (13, 16). In the United States, 10 to15 million people are estimated to have latent TB (LTB), an infection that is asymptomatic and noninfectious (13). The identification and appropriate treatment of people with LTB is necessary to control TB, since some of these individuals will develop active TB if not properly managed (13).The tuberculin skin test (TST) was, until recently, the only available method used to detect LTB (2,4,5,7,10,14). However, problems are associated with the TST such as a high false-positivity rate, interference by the Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccination and a delayed result which requires two visits to the clinic, one for placement of the TST and another to evaluate the results of testing. This high false-positivity rate also leads to unnecessary procedures such as a chest X-ray (CXR), a more extensive systemic review, and isoniazid (INH) therapy (11,14).The QuantiFERON-TB Gold test (QFT-GT; Cellestis Limited, Carnegie, Victoria, Australia) was recently approved by the FDA as a screening test to detect for active 16). This assay tests whole blood and uses the enzymelinked immunosorbent assay format to detect gamma interferon, a cytokine secreted by sensitized T cells in response to specific Mycobacterium tuberculosis complex antigens which is absent from the vaccine strain of BCG (8)(9)(10)(11)16). This study was conducted to assess the cost of using a two-step process of evaluating new health care employees with positive TST results with the QFT-GT as a means to eliminate unneeded follow-up and treatment.(This research was presented at the 109th General Meeting of the American Society for Microbiology, 17 to 21 May 2009, Philadelphia, PA.)A total of 242 participants presenting to Employee Heath during preemployment screening between April 2006 and April 2008 were enrolled in this study. The ages of the participants ranged from 18 to 64 years, with 141 females and 101 males. Of the participants, 123 were foreign born in thirdworld countries located in Africa, the Middle East, Southeast Asia, and Central and South America. New employees were asked to complete a questionnaire that included the presence of medical conditions such as human immunodeficiency virus infection, diabetes, chronic pulmonary diseases, and previous TB disease, as well as risk of exposure to TB (such as close contact with patients with active TB or living/traveling in an area where TB is highly endemic), a history of BCG vaccination, and previous TST results. In addition, individuals with previous positive TST results were asked...