Herpes is a very common viral infection throughout the world, it can be caused by either strain of Herpes Simplex Virus (HSV), designated HSV-1 and HSV-2. The HSVs, although commonly associated with Oral and Genital Herpes, are responsible for various clinical manifestations, including: cutaneous infections ( whitlow, herpes gladatorlum); ocular infections, neonatal herpes, herpes encephalitis, disseminated infection and erythema multiform. [66] Of these various manifestations, Oral and Genital Herpes are, by far, the two most common disease expressions caused by these viruses. Unfortunately, to date, there is no conclusive data revealing the exact extent of the virus's infiltration into the human population, but the number of sufferer's worldwide is estimated to be at approximately 86 million people as of 1999. [1]  To understand the rate of increase of HSV infection, in the United States, the prevalence of  HSV-2 infection has increased by approximately 30 percent since the late 70ís.  So currently, it is believed that over 500,000 new cases of genital herpes occurs annually in the US alone. [77] In order to understand this pandemic further, HSV-1, HSV-2's counterpart, may infect as many as 20%-40% of some populations, whom are estimated to have recurrent oral-facial HSV infection. [77] The estimate regarding Genital herpes has placed it as one of the 3 most prevalent STDís in the United States, which raises the most concern apart from HIV in sexually active people. [2]

        The recent concern of secondary infections, such as HIV, coupled with desire to help clarify issues concerning the true prevalence rates of genital herpes has prompted new serological methods based on the detection of type-specific antibodies to Herpes Simplex Virus (HSV) glycoproteins. [1] In detecting these incidences, it is important to keep in mind that oral and genital herpes are infections that can occur from either HSV-1 or HSV-2, although there are stronger correlation's with HSV-1 causing oral herpes and HSV-2 causing genital herpes.  Also, it is imperative to realize, because of the expense and availability of testing, coupled together with the lack of reporting disease, result in the probability of current estimates of prevalence being low. [2] These low estimates are also  influenced by the number of persons who do not seek attention for active infection expressing disease or by actively infected persons with non-expression of the disease. In comparison, the true prevalence rates of HSV-1 oral infection is unknown, because of mainly the same reasons. To make matters worse, these patient's ignorance of their infection along with the occurrence of atypical symptomology and asymptomatic viral shedding of HSV has contributed to the increases in transmission of HSV. [1] Unfortunately, in the past, HSV did not receive much attention for eradication because it was not considered an "emergency" disease, since it is not typically life threatening, except in the rare incidences of Neonatal Herpes infection and the rare incidences of HSV induced encephalitis. This view has been altered radically because of the increasing association of HIV transmission within HSV infected patients. Truthfully, the most important risk factor in the acquisition and transmission of Human Immunodeficiency Virus (HIV) is Genital ulcer disease, of which genital herpes is the most common cause within developing countries [1]

         Elsewhere in the World has similar findings. In Scandinavia, the seroprevalence of HSV-2 infection in pregnant women nearly doubled over the past two decades, from 19% to 33%. Data presented at the recent annual meeting of the International Herpes Management Forum indicated that 25% of men and women attended STD clinics in the United Kingdom, 14% to 90% of STD clinic attendees in Sweden, and 5% to 40 % in various other populations in Europe are infected with HSV-2.  Seroprevalence rates in the developing world are even higher. For example, among gold miners in South Africa and commercial sex workers in Africa, HSV- 2 seroprevalence rates are 60% to 90%. [2]

Factors influence the seroprevalence of HSV-2:

• Social/economic factors
• Sexual history (years of sexual activity)
• Age
• HSV-1 antibody status
• Positive history of other STDs
• number of sexual partners

In regards to the seroprevalence of HSV-1, it was found that in approximately 20% of children younger than 5 years of age were positive for antibodies against HSV-1, which rises in a nearly linear fashion through the age of 70 years. [2]  The prevalence increases in this way so by the time Americans become teenagers or young adults, about 50% have HSV-1 antibodies in their blood and by the time Americans are over age 50, some 80-90% of Americans have HSV-1 antibodies. These antibodies are related to the most common type of herpes, caused by HSV-1, which is acute herpetic gingivostomatitis.

HSV-1 acute herpetic gingivostomatitis

Growing Concern

Favorably, growing concern regarding HSV infections has been gaining media attention in the past two decades because the high level of concern among sexually active persons. The National STD hotline, funded by the Center of Disease Control, receives about 60,000 herpes related calls a year. [2] A known central problem is the high proportion of genital HSV infections that are unrecognized by clinicians and patients, of which only ? to 1/3 of infected persons tend to even acknowledge symptoms. The diagnosis of Genital herpes increases greatly when sensitive diagnostic tests, such as viral culture and type-specific serological tests are made to clinicians. [2] A critical issue in understanding the epideomology of HSV-2 infection is the recent recognition that more than 85% of persons who have HSV ?2 antibodies do not report lesions and nonetheless shed the virus from the genital track. Thus the large majority of HSV-2 seropositive persons intermittently shed virus from mucosal surfaces and serve as reservoirs for the potential spread of HSV as previously mentioned. [2] Emerging data suggest that reactivation and viral shedding persist for at least 8-10 years and gives reason to believe that the current rate of infected individuals is probably higher.

 HSV and Pregnancy

        During pregnancy , HSV infection is associated with spontaneous abortion, prematurity and congenital neonatal herpes. [64] The most serious direct consequence of genital HSV infection is neonatal herpes, which results from perinatal transmission from mother to infant.  Currently 20-25 percent of pregnant women have genital herpes which poses a risk of infection to their fetus. HSV is acquired by the neonate during labor in about 90% of cases of neonatal herpes through direct contact with infected maternal genital secretions. While in utero, a further 5% of cases occur (either ascending infection or transplacentally) and the remaining 5% of cases HSV is acquired post-partum. Transmission is greatly influenced by the mother's serological status. If HSV-1 or HSV-2 was recently acquired and the mother is seronegative, then 15% to 50% of vaginally delivered babies will acquire infection. Compared to a 1% transmission rate in women with long standing infection.  Traumatically, untreated neonatal herpes has among the highest mortality rates of any infection in the neonatal period, upward of 60%, and most survivors suffer crippling developmental defects. [2] The incidence of disseminated neonatal HSV infection is unknown, but has been estimated to be approximately one in every 10,000 births. [77] Using Acyclovir therapy, the mortality rate is reduced to 10%, but neurological sequelae remain common. Current standards of care in the United States dictate cesarean delivery for women with active genital herpetic lesions.

                                                                                                            Congenital Herpes  [53]
 

What Are the Symptoms of Herpes Infection in the Newborn?

        Some infected newborns develop skin or mouth sores or eye infections. When the infection remains limited to these organs, an infected baby should go on to develop normally. Unfortunately, herpes infections in newborns often spread to the brain and many internal organs. These babies may appear irritable, eat poorly and suffer from seizures. Even with treatment, about half of these infants die or develop serious brain damage that
can result in mental retardation, cerebral palsy, seizures, blindness or deafness. [58]
 
 

The placenta as a barrier to infection

The placenta appears to be an effective barrier to prevent infection of the fetus in maternal HSV infection. The fetus is rarely infected in utero, nevertheless, congenital infection can occur. Infants infected in utero are usually premature and the mortality rate is high.

Ocular
    Acting as a neurotropic virus, HSV is the major cause of corneal blindness in the world today especially with Secondary recurrences from latency. [45] (Pathologies)
 
 

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