Reassessment of selected healthcare associated risk factors for HBV and HCV infections among volunteer blood donors, Karachi, Pakistan.

Epidemiologic studies conducted in the 1990s identified several independent healthcare associated risk factors for HBV and HCV infections in Pakistan. In 2002, we re-examined healthcare associated HBV and/or HCV infection risk factors in volunteer blood donors. In this case-control study, we collected data using a structured questionnaire on socioeconomic attributes, putative healthcare related risk factors, and other known factors for HBV and HCV infections in Karachi, Pakistan. The multivariable logistic-regression model (166 cases, 394 controls) after adjusting for socio-demographic attributes and other known HBV and HCV risk factors revealed that more cases than controls had multiple lifetime hospitalization, adjusted odds ratio (AOR) = 2.48; 95% confidence interval (CI) 1.04, 5.94, and had received dental treatment from an unqualified provider (AOR = 5.90, CI, 1.66, 21.02). More cases than controls had received a large number of therapeutic injections during the last 5 years (1-5 injections vs. 0, AOR = 2.64, 95% CI 1.06, 6.60; 6-19 injections vs. 0, AOR = 4.09, 95% CI 1.59, 10.51; > or = 20 injections vs. 0, AOR = 4.34, 95% CI 1.70,11.07), and had their last injection given using a re-usable glass syringe (AOR = 3.41 CI 1.13, 10.29). Our data suggest that risk factors for HBV and HCV infections identified in the last decade have remained unchanged in healthcare facilities in Karachi. Additional multi-disciplinary efforts are needed to control healthcare associated HBV and HCV transmission in Pakistan.