The herpes simplex virus type 2 (HSV-2) is a double-stranded DNA virus with tropism neurological and mucocutaneous. The infection is usually acquired through sexual contact and causes genital ulceration. Persistent infection may be a source of clinical relapses. The application of new diagnostic procedures provided further insights into the biological interactions between HIV and caused by human immunodeficiency virus (HIV).
Seroprevalence studies revealed a high frequency of herpes symptoms in some Western countries, and greater even those in developing countries. The state of HSV-2 infection may represent a useful marker of sexual behavior. In fact, in many countries of sub-Saharan Africa, the epidemic of HSV-2 occurred in parallel with that caused by HIV.
Most infections go unnoticed. Susceptible individuals have primary infection after the first exposure to HSV-1 or HSV-2, genital lesions may be associated with significant morbidity. The first episode may be accompanied by systemic manifestations, complications are rare in men but aseptic meningitis and urinary retention are more common in women. During the latency period, subclinical or asymptomatic viral shedding is frequent. Patients in whom the initial episode was more severe with a high rate of recurrence. In most investigations, the percentage of symptomatic infections and recognized between 13% and 37%, is higher in HIV positive subjects.
Most injuries are caused by genital herpes HSV-2 but increasingly there are more symptoms related to infection with HSV-1. Prospective studies showed that transmission is not usually associated with a recurrence clinically recognized. In a similar way to other sexually transmitted diseases, infection with HSV-2 is more common in women, probably related to biological and anatomical factors.
The frequency of clinical recurrence and asymptomatic phase is significantly lower in HSV-1 infection and do not appear to be differences among individuals infected with both herpes symptoms in men virus for those infected with HSV-2 only. The polymerase chain reaction (PCR) detected the virus in mucocutaneous surface much more frequently than viral culture.
The HSV-1 and HSV-2 can cause genital herpes primarily, in some centers, the HSV-1 is the causative pathogen half of those injuries.
In Western countries the incidence of HSV-1 infection in children is declining and many teenagers become infected by HSV-1 with the sexual initiation. However, the HSV-1 reactivates less frequently than HSV-2, so that most clinical recurrences are attributable to the latter.
A U.S. population study in 1996 revealed an incidence of seropositivity for HSV-2 from 22%, 30% higher than that recorded 10 years earlier despite education programs in the decades of 80s and 90s in response to the epidemic HIV. Another study, in Baltimore, USA, revealed a frequency of HSV-2 infection by 81% in subjects HIV positive homosexual or heterosexual.
In sub-Saharan Africa, epidemiological studies showed a high rate of infection in adults: 40% in Kinshasa and Zimbabwe, over 65% in Tanzania and Uganda and up to 82% in the Republic South Africa . In these countries, HSV-1 infection is endemic and is acquired during childhood, while the prevalence of Herpes symptoms rises sharply since adolescence. In Asia, the frequency of HSV-2 infection varies from 6% in the general population to 50% in high-risk groups.
Numerous epidemiological studies showed that chancroid, syphilis and genital herpes are common cause of genital ulcer lesions in developing countries. However, the first two situations appear to have declined in recent years as herpetic ulcers are becoming more frequent in HIV positive patients and HIV negative.
A good correlation was found between the prevalence of antibodies antiHSV-2 and the number of sexual partners throughout life, especially in males. Unlike what was observed in industrialized countries, the prevalence of infection appears to be unrelated to the age of first sexual contact.
Serology for HSV-2 can be a useful biomarker to identify changes in patterns of sexual behavior in the studies evaluating the intervention in HIV infection, as HSV-2 is sexually transmitted more easily than HIV. In this context, a recent study in young South Africa showed that HIV infection is associated with HSV-2 seropositivity and sexual behavior.