Background: Undiagnosed cases of transmissible blood-borne viruses (HCV and HIV) result in significant morbidity and mortality, further spread of epidemics, and increased public health costs. Testing in emergency departments (EDs) is an opportunity for expanding HIV and HCV screening. The goal of this project was to increase the proportion of eligible patients screened for HIV and HCV in urban areas. Methods: An opportunistic automated screening program for HIV and HCV was implemented in the EDs of 4 public hospitals in Spain and Portugal at different periods between 2018 and 2022. HIV and HCV prevalence was prospectively evaluated. In case of anti-HCV or anti-HIV reactive test results, reflex testing was done for confirmation. Results: More than 90% of the population eligible for testing were screened in the participating centers. We found a seroprevalence rate of 0.7% for HIV and seroprevalence rates ranging from 0.6% to 3.9% for hepatitis C. Between 19% and 53% of individuals who tested positive for HCV antibodies were viremic. Conclusions: Opportunistic HIV and HCV screening in EDs is feasible, does not disrupt ED activities, is highly effective in increasing diagnosis, and contributes to WHO goals for the elimination of HIV and hepatitis C.
