The chapter describes various viral infections. Herpes simplex virus (HSV) is the one that causes contagious sores, most often around the mouth or on the genitals. Virus remains latent in sensory ganglia after primary episode from where it periodically reactivates. HSV1 causes orolabial herpes and HSV2 is responsible for genital herpes. Antivirals like acyclovir, famciclovir, valaciclovir are given during clinical episodes as a treatment. Varicella zoster virus (VZV), also called human herpes virus-3, causes varicella infection. Pityriasis rosea, from the combination of pityriasis which means powdery scale and rosea meaning pink, is the common acute disease typically beginning as a single oval scaly plaque on the trunk (herald patch or mother patch). Other topics covered are Kaposi’s sarcoma, human papilloma virus, measles, rubella, erythema infectiosum, roseola infantum, molluscum contagiosum, etc.