Cullins explains that even if you’ve never had an outbreak, if you’ve been exposed to herpes, it lies dormant in your body. A blood test could reveal antibodies for HSV-1 and/or HSV-2, which means that you have been exposed to the infection in your past, you have been infected, and you have developed antibodies because your body has or is fighting the infection.
The herpes simplex virus is probably the most well-known virus of the herpes family, and it is just as contagious. Herpes simplex infects epithelial cells and remains latent in neurons. HSV-1 causes recurrent oropharyngeal lesions, commonly known as “fever blisters" or "cold sores.” It is also the primary cause of sporadic encephalitis (inflammation of the brain), gingivostomatitis (inflammation of the gums and mucous lining of the mouth), and keratoconjunctivitis (severe dryness of the eye that involves the cornea) and dendritic corneal ulcers (also called HSV keratitis) in which the cornea becomes affected by herpetic lesions that look like the dendrites of neurons in the brain.
Research has gone into vaccines for both prevention and treatment of herpes infections. Unsuccessful clinical trials have been conducted for some glycoprotein subunit vaccines. As of 2017, the future pipeline includes several promising replication-incompetent vaccine proposals while two replication-competent (live-attenuated) HSV vaccine are undergoing human testing.
Antibodies that develop following an initial infection with a type of HSV prevents reinfection with the same virus type—a person with a history of orofacial infection caused by HSV-1 cannot contract herpes whitlow or a genital infection caused by HSV-1. In a monogamous couple, a seronegative female runs a greater than 30% per year risk of contracting an HSV infection from a seropositive male partner. If an oral HSV-1 infection is contracted first, seroconversion will have occurred after 6 weeks to provide protective antibodies against a future genital HSV-1 infection. Herpes simplex is a double-stranded DNA virus.
At least 80 to 90 percent of people in the U.S. have already been exposed to the HSV-1 virus.sup style="font-size: 10px;">21 Meanwhile, around 3.7 billion HSV-1 infections were recorded in 2012 all over the world, according to the World Health Organization. Africa was home to the highest number of cases, with 87 percent of occurrences coming from this continent.22
A 2004 study in the New England Journal of Medicine found that suppressive therapy decreases the risk of HSV-2 transmission from symptomatic, infected partners to uninfected partners by 48%. So “the risk of transmission is significantly reduced, but cannot be eliminated even with suppressive therapy,” Johnston explains, and she stresses that the virus can be passed along even without signs or symptoms.