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Prevalence of latent TB among health care workers in four major tertiary care hospitals in Riyadh, Saudi Arabia.

BACKGROUND
Tuberculosis (TB) infection represents a global health problem and a great risk to Health Care Workers (HCWs). Identifying individuals, particularly HCWs with latent tuberculosis infection (LTBI) will support TB control through chemoprophylaxis and prevent cross-infection.


OBJECTIVES
This study aimed to identify prevalence of Latent TB among a two-year new hires of HCWs in 4 major tertiary care hospitals in Riyadh, Saudi Arabia.


MATERIAL AND METHODS
2650 recently (2-years) hired HCWs were surveyed for latent TB using Tuberculin Skin Test (TST). Data was collected from January 2008 to December 2009. Induration due to TST equal to or more than 10 mm. within 48-72 hours was considered positive. The results of TST were correlated with other variables such as age group, gender, job category, country of origin.


RESULTS
as an overall rate, 291(11%) out of 2650 were positive for TST, with the highest significant positive rates among physicians (14.9%) and nurses (12.9%) compared to students as a reference group. No statistically significant difference was detected between both sexes. The highest significant positive TST rates were found among HCWs in the age group of 50 years and older (32.6%) compared to 10-19 years age group as a reference group, and among HCWs coming from sub-Saharan countries (61.1%) compared to Saudi HCWs with the lowest positive rates (5%) as a reference group.


CONCLUSION AND RECOMMENDATIONS
LTB is prevalent among newly hired HCWs in Riyadh tertiary hospitals. Standard programs for detection and treatment of LTB should be encouraged.