Herpes Genitalis As a Clinically Significant Sexually Transmitted Viral Disease

Several viruses may be transmitted by sexual contact. Important among them are herpes genitalis, genital warts virus, molluscum contagiosum, virus B hepatitis, cytomegalovirus and Marburg virus.

Herpes Genitalis

Herpes genitalis is caused usually by Herpes simplex virus (HSV) type 2 and less frequently by HSV type 1. It is moderately infectious. The virus remains dormant in the presacral sensory ganglion cells. Periodically, it moves into the skin through the axons of sensory nerves to produce recurrent attacks of herpes simplex locally. Factors which produce the reappearance of herpes are not clear. In many western countries, herpes genitalis is emerging as the commonest among the STD. The disease is transmitted by sexual intercourse. The virus is shed from the lesions for up to 2 weeks after apparent healing. Infection of the baby during birth leads to neonatal herpes.

Clinical features: The incubation period is 2 to 4 days or rarely longer. The onset of local lesions may be preceded by burning pain in the S₁ and S₆ dermatomes. The lesions occur in the external genitalia of men and in the anal canal of homosexuals. Over the penis, it starts with erythema followed by the appearance of papules or vesicles which soon rupture to form shallow painful ulcers. Ultimately, crusts form which dry up and fall off leaving healed scars which fade. Tender inguinal adenopathy develops in the primary attack but not with recurrences. The lesions are infective throughout. Recurrences are generally much milder. In women, the primary lesion and recurrent attacks differ from each other considerably. Primary attack is severe, whereas subsequent attacks are milder. Lesions occur usually in the vulva and adjacent skin areas. Morphology of the lesion is the same as in men. During the primary attach, retention of urine may develop dye to extreme pain on micturation. Herpes virus infection may be directly or indirectly related to the development of carcinoma of the cervix, vagina or vulva in later life.

Dissemination of the infection is rare in adults, but if it occurs, it can be fatal. The skin, the central nervous system and other internal organs may be affected. The newborn may acquire herpes during its passage through infected maternal tissues. Lesions develop usually within two weeks after birth. These occur more commonly with primary maternal herpes than with recurrent attacks. Both HSV-1 and HSV-2 may be responsible . Lesions may be localized or dissemination may occur. In the latter case, mortality is high. Disseminated herpes affects the central nervous system.

This is established by isolation of the virus. Blood should be taken for complement fixation test and this should be repeated after two to three weeks to determine changes in the titer. In primary infection, the first sample is seronegative, the second sample shows a marked rise in titer. In recurrent herpes both samples give the same low titer.