UNIVERSITY PARK, Pa. -- Human herpesvirus, commonly known as herpes simplex virus 1 and 2 (HSV-1 and HSV-2), is like that friend who ends up crashing on your couch and never leaves.
Most of the time he lurks in the background, relatively innocuous but for the annoying thought of his presence. But occasionally he comes out of the shadows and ends up in the way in your kitchen at mealtime, uninvited and naturally wanting a little something for himself. Later he interrupts an intimate moment with a perfectly timed and inopportune knock at your bedroom door; and as time drags on, he generally spoils your good times by managing to be everywhere you wish he wouldn't be at precisely the wrong moments.
But unlike your couch-crashing "friend," you can't just put herpes out on the street and be done with it.
And worse yet, the Centers for Disease Control and Prevention estimate that, in the United States alone, herpes infects more than three-quarters of a million new people every year.
Moriah Szpara, assistant professor of biochemistry and molecular biology at Penn State and researcher at the Huck Institutes of the Life Sciences, aims to find a cure for the disease.
"Herpes simplex virus type 1 is fairly ubiquitous around the world," she says. "About 70 percent of all adults have seropositivity, meaning that they have signs of exposure to this virus in their bloodstream, and a fraction of those people suffer cold sores or genital sores -- depending on the site of introduction -- periodically for the rest of their lives."
Beyond being a simple, periodic annoyance, herpes sometimes exhibits hypervirulence: running amok in its host and causing blindness, aseptic meningitis (inflammation of the protective membranes covering the brain and spinal cord), or encephalitis (swelling of the brain). The latter two conditions can be fatal.
In fact, HSV-1 is the leading cause of infectious blindness in the United States and is the main cause of sporadic, fatal encephalitis. Because the drugs currently available to treat HSV treat only the virus's active, replicating phase and associated symptoms (for example, oral and genital sores), they do not affect its latency in neurons, which is what allows herpes to infect its host for life.
"In a very small number of cases that we don't understand the reason for, the virus can progress into the central nervous system and cause encephalitis," says Szpara, who is also a faculty member of the Bioinformatics and Genomics graduate program. "Because we don't know why it happens, we can't predict it and we can't stop it. Right now, the infection is permanent, and that's the biggest public health issue surrounding herpes -- it's a dangerous virus, it's not benign, it's not friendly, and the infection will never go away."