Until the 1980s serological tests for antibodies to HSV were rarely useful to diagnosis and not routinely used in clinical practice. The older IgM serologic assay could not differentiate between antibodies generated in response to HSV-1 or HSV-2 infection. However, a glycoprotein G-specific (IgG) HSV test introduced in the 1980s is more than 98% specific at discriminating HSV-1 from HSV-2.
Genital herpes is passed on by skin-to-skin contact during vaginal, oral or anal sex, or by sharing sex toys. You can get genital herpes even if there are no visible sores or blisters, and once you have the virus, there is no cure. 'Herpes is more likely to be passed on just before, during or straight after an outbreak, as herpes blisters and sores are highly infectious,' says O’Sullivan.
Herpes is contracted through direct contact with an active lesion or body fluid of an infected person. Herpes transmission occurs between discordant partners; a person with a history of infection (HSV seropositive) can pass the virus to an HSV seronegative person. Herpes simplex virus 2 is typically contracted through direct skin-to-skin contact with an infected individual, but can also be contracted by exposure to infected saliva, semen, vaginal fluid, or the fluid from herpetic blisters. To infect a new individual, HSV travels through tiny breaks in the skin or mucous membranes in the mouth or genital areas. Even microscopic abrasions on mucous membranes are sufficient to allow viral entry.
However, asymptomatic carriers of the HSV-2 virus are still contagious. In many infections, the first symptom people will have of their own infections is the horizontal transmission to a sexual partner or the vertical transmission of neonatal herpes to a newborn at term. Since most asymptomatic individuals are unaware of their infection, they are considered at high risk for spreading HSV.
There are two types of herpes simplex viruses (HSV), they are termed HSV-1 and HSV-2. These two viruses have distinctly different DNA, and both cause oral and genital lesions. However, HSV-1 causes about 80% of all oral lesions and only about 20% of genital lesions while HSV-2 causes the reverse (about 80% genital and 20% oral). Studies also suggest that in adolescents, up to 40% of genital herpes is caused by HSV-1 because of reported increased oral/genital contact (transmission by oral sex).
In all cases, HSV is never removed from the body by the immune system. Following a primary infection, the virus enters the nerves at the site of primary infection, migrates to the cell body of the neuron, and becomes latent in the ganglion. As a result of primary infection, the body produces antibodies to the particular type of HSV involved, preventing a subsequent infection of that type at a different site. In HSV-1-infected individuals, seroconversion after an oral infection prevents additional HSV-1 infections such as whitlow, genital herpes, and herpes of the eye. Prior HSV-1 seroconversion seems to reduce the symptoms of a later HSV-2 infection, although HSV-2 can still be contracted.
Although the cause is unknown, outbreaks are often associated with periods of weakened immune systems, skin wounds, menstruation, fever, nerve damage, tissue damage from surgery, or exposure to extreme climate situations. A genital herpes outbreak or episode occurs when the HSV-1 or HSV-2 virus is reactivated from its dormant stage. Genital herpes is an incurable disease, and once you contract it, you may experience outbreaks throughout your lifetime. Those who are experiencing their first herpes episode of genital herpes can expect to have several (typically four or five) outbreaks within a year. Over time these recurrences usually decrease in frequency and severity. The first outbreak of herpes is often the longest outbreak experienced. After that, short and inconsistent episodes can be managed and treated with antiviral medication.
Herpes virus type 4 is also called Epstein-Barr virus. It typically causes infectious mononucleosis, a “kissing” disease. Symptoms include skin rash, fever, sore throat and swollen lymph glands. The virus can be involved in cancers like nasopharyngeal cancer. Herpes virus type 4 is contagious through bodily fluids, including saliva. Kissing, coughing, sneezing, or sharing utensils can make the infection spread.