Sadeq R, Mohtady H, Al Badawy N, Ibrahim S, Omar AR, Husseiny MI, El Zowalaty M (2013) Endogenous IFNγ in chronic HCV genotype 4 patients treated with PEG-IFNα and ribavirin. J Infect Dev Ctries 7:859–867. doi: 10.3855/jidc.2937