viernes, 5 de octubre de 2012

Notes from the Field: Tuberculosis Outbreak in a Long-Term–Care Facility for Mentally Ill Persons — Puerto Rico, 2010–2012

Weekly
October 5, 2012 / 61(39);801-801

During January 2012, the Puerto Rico Department of Health (PRDOH) detected a tuberculosis (TB) outbreak among residents of a long-term–care facility in the San Juan metropolitan area. The same rare Mycobacterium tuberculosis genotype was identified in isolates from four patients. This facility housed 40 men, aged 40–71 years, with severe mental illness. During April 2012, CDC assisted PRDOH with the investigation to describe outbreak epidemiology, identify and prioritize contacts for evaluation and treatment, and provide recommendations on interventions aimed at stopping TB transmission.
A confirmed case was defined as TB disease diagnosed during July 2010–April 2012 in a facility resident caused by M. tuberculosis with the outbreak genotype; a probable case was TB disease during the same period in a facility resident without isolates available for genotyping analysis but with epidemiologic links to a confirmed case. Four confirmed and three probable cases were identified. Median age of the seven men was 52 years (range: 49–71 years), and none had evidence of human immunodeficiency virus infection. Three patients died; two died of respiratory failure presumed to be related to TB, the third died of cardiorespiratory arrest of unknown etiology. Patients were considered to be infectious from 3 months before development of symptoms if they had acid-fast bacilli in their sputum or cavitary lesions on chest radiography or from 1 month before onset of symptoms for other cases, to 14 days after the beginning of treatment (1). The median estimated length of time the patients were infectious at the facility was 99 days (range: 91–214 days). A review of medical records identified a possible eighth TB case in a facility resident who had died of respiratory failure in April 2011 without testing for TB.
Since the initial case was identified in July 2010, tuberculin skin tests were administered to 187 contacts during 2010–2012; 26 (81%) of 32 residents and seven (5%) of 155 nonresident contacts (facility employees and residents' family members) had evidence of latent TB infection. Among residents, median time between a positive tuberculin skin test and chest radiography was 29 days (range: 3–515 days) and between chest radiography and latent TB infection treatment initiation was 66 days (range: 15–555 days). The congregate setting, with extended close contact among facility residents and extended infectious periods provided a prolonged opportunity for exposure. Contributing factors for the extended infectious periods included the local TB clinic's lack of on-site radiography equipment, delays in preapproval for radiographs among Medicaid beneficiary residents, and difficulty in transporting residents with severe mental illness to a medical facility.
To prevent similar outbreaks, PRDOH recommended more timely access to medical services for facility residents, placement of radiography equipment at the TB clinic, and dissemination of educational materials to facility employees. CDC guidelines recommend TB education, symptom screening, and possibly testing of new employees and residents of long-term–care facilities (2,3). Because of difficulties with symptom screening among persons with severe mental illness, PRDOH recommended that new residents undergo more intensive screening (e.g., tuberculin skin testing, chest radiography, and sputum evaluation) before admission to long-term–care facilities in Puerto Rico.

Reported by

Johnny V. Rullán, MD, Brenda Rivera-García, DVM, Maria Bermúdez, MPH, Miguel Fernández-Vásquez, Puerto Rico Dept of Health. Sapna Bamrah, MD, Bruce Health, Div of TB Elimination, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention; W. Randolph Daley, DVM, Div of Applied Sciences, Scientific Education and Professional Development Program Office; Sara Auld, MD, Kanako Ishida, PhD, EIS officers, CDC. Corresponding contributor: Kanako Ishida, kishida@cdc.gov, 404-553-7635.