Canker sores are sometimes thought to be caused by HSV, but this is not true. Canker sores occur only inside the mouth, on the tongue, and on the soft palate (roof of mouth), not on skin surfaces. Although they reoccur, they are not contagious, usually are self-limiting, and have almost no complications. Canker sores are caused by substances that irritate the lining of the mouth.
Traditionally, it was assumed that HSV-1 strictly caused oral sores and blisters, whereas HSV-2 caused genital and/or rectal sores and blisters. However, the virus- or perhaps just our understanding of the virus itself- has evolved in such a way that doctors now recognize that either HSV-1 or HSV-2 can cause genital and/or rectal sores, albeit with HSV-2 causing the majority of sores in the genital or rectal areas.
However, there is much more to the herpes virus than just chicken pox or genital herpes. For instance, after an active infection, the virus is shed (eliminated) in the urine and feces for up to several months (sometimes years in the case of the cytomegalovirus) after the active infection has resolved. This means the infected person is still contagious, which is what makes this virus so contagious. It can easily be transferred when the patient is asymptomatic.
A scary finding is that more cases of genital herpes than ever before are now being caused by HSV-1 (the type most people assume only causes mouth sores), and about 85 percent of people with genital herpes don’t even know it. (7) Studies show that about 50 percent of the new genital herpes infections in young adults are due to HSV-1 and about 40 percent in older adults. The fact that most people don’t ever find out they’re infected is one of the reasons that transmission rates are steadily climbing.
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.
The “classic” symptoms that most people associate with genital herpes are sores, vesicles, or ulcers – all of which can also be called “lesions.” (The scientific literature on herpes uses the term “lesion” to describe any break or irregularity in the skin.) These classic lesions of genital herpes often resemble small pimples or blisters that eventually crust over and finally scab like a small cut. These lesions may take anywhere from two to four weeks to heal fully.
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.
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.