Acute HCV: systemic PBMC response Dr. Kamal follows a population of Egyptian health care workers who become infected acutely with HCV, and she routinely isolates PBMCs from them. This clinical population is composed primarily of Genotype 1 and Genotype 4 infected individuals, and is thoroughly described for patient demographics, RNA titer at the time of blood collection, and progression to chronic infection. Given the relative rarity of Genotype 4 in our local population our initial analysis will focus on Genotype 1 acute HCV, but we intend to study genotype 4 as well, since this genotype has great relevance to HCV worldwide. Based on our previous work we anticipate needing between 10-20 patients in a given group in order to clearly define consistent gene expression changes across a spectrum of clinical variability. We expect to collect and study PBMC samples from at least 20 acute genotype 1 patients per year. Samples from 20 healthy control volunteers will also be obtained over the 3 year study period (recruited by poster).