Tuberculosis risk among staff of a large public hospital in Kenya

SETTING: In sub-Saharan Africa, high rates of tuberculosis (TB) and human immunodeficiency virus (HIV) infection pose a serious threat for occupationally acquired TB among health care workers. OBJECTIVE: To identify factors associated with TB disease among staff of an 1800-bed hospital in Kenya. DESIGN: We calculated TB incidence among staff and conducted a case-control study where cases (n = 65) were staff diagnosed with TB and controls (n = 316) were randomly selected staff without recent TB. RESULTS: The annual incidence of TB from 2001 to 2005 ranged from 645 to 1115 per 100000 population. Factors associated with TB disease were additional daily hours spent in rooms with patients (adjusted odds ratio [aOR] 1.3, 95%CI 1.2-1.5), working in areas where TB patients received care (aOR 2.1, 95%CI 1.1-4.2), HIV infection (aOR 29.1, 95%CI 5.1-167) and living in a slum (aOR 4.7, 95%CI 1.8-12.5) or hospital-provided low-income housing (aOR 2.6, 95%CI 1.2-5.6). CONCLUSION: Hospital exposures were associated with TB disease among staff at this hospital regardless of their job designation, even after controlling for living conditions, suggesting transmission from patients. Health care facilities should improve infection control practices, provide quality occupational health services and encourage staff testing for HIV infection to address the TB burden in hospital staff.