. . . . . "However, vaccines have not yet been developed for some viruses such as human immunodeficiency virus, hepatitis C virus, herpes simplex virus (HSV), cytomegalovirus, and most hemorrhagic fever viruses (except for yellow fever virus) [1].VZV causes 2 distinct diseases: chickenpox (varicella) and shingles (herpes zoster [HZ])." . .