Abstract
Herpes infections are among very common diseases and are manifested with skin symptoms. They are caused by DNA viruses that are antigenically homogeneous.
Human is the only virus source and host. Seroprevalence of the population is very high.
Herpes simplex and varicella are the most common conditions. Papillomavirus infections are caused by human papillomaviruses (HPV) that belong to DNA viruses.
They most frequently induce the formation of verruca and condylomata. Condylomata are transmitted sexually and associated with risks.
Their incidence is increasing worldwide. The exact prevalence of verruca is unknown but it is estimated to affect 7%-12% of the population.
At times, spontaneous regression of the disease occurs, but infection in the cells can persist and treatment is difficult. Some types of HPV cause dysplasias which are considered to be precancerous conditions.
They include certain skin warts induced by HPV type 5 and lesions in the uterine cervix caused by HPV types 16, 18, 33, and 52. The occurrence of these papillomaviruses has also been described in other types of tumours.
The latency period from exposure to tumour development can be several years.