Herpes

Lore & Background

Herpes infections are categorized by the area of the body infected. Oral herpes involves the face or mouth, often resulting in small blisters called cold sores. Genital herpes involves the genitalia and may form blisters that break into small ulcers, typically healing over two to four weeks. The first episode is often more severe and may include fever, muscle pains, swollen lymph nodes, and headaches. Over time, episodes decrease in frequency and severity. Other forms include herpetic whitlow (fingers or thumb), herpes simplex keratitis (eye), herpesviral encephalitis (brain), and neonatal herpes (newborn). There are two virus types: HSV-1 more commonly causes oral infections, while HSV-2 more commonly causes genital infections. After infection, the viruses travel along sensory nerves to nerve cell bodies, where they remain lifelong. Recurrence triggers may include decreased immune function, stress, and sunlight exposure. Diagnosis is usually based on symptoms and can be confirmed by PCR testing or viral culture; blood testing for IgG antibodies can confirm past exposure but may yield false negatives during the seroconversion window. Worldwide, HSV-1 is usually acquired during childhood. Rates of HSV-1 are between 70% and 80% in populations of low socioeconomic status and 40% to 60% in populations of improved socioeconomic status. Most people with HSV-2 do not realize they are infected.

Reader's Guide

Herpes simplex is significant as one of the most common viral infections in humans, affecting the majority of the global adult population. Its importance lies in its lifelong persistence, periodic symptomatic episodes, and potential for severe complications in immunocompromised individuals, newborns, and those with certain genetic factors. The infection is transmitted through direct contact with body fluids or lesions, including asymptomatic shedding, which makes prevention challenging. Genital herpes is classified as a sexually transmitted infection and can be spread to an infant during childbirth. There is no available vaccine and no cure; treatment focuses on symptom management with antiviral medications such as aciclovir or valaciclovir, which can lessen the severity of episodes, and supportive measures like paracetamol and topical lidocaine. The most effective method of avoiding genital infections is by avoiding vaginal, oral, manual, and anal sex, while condom use decreases risk. Daily antiviral medication taken by an infected person can also reduce spread. The condition has been associated with cognitive deficits in bipolar disorder and Alzheimer's disease, though this is often dependent on the genetics of the infected person. The name derives from Ancient Greek meaning 'to creep', referring to spreading blisters.

Did You Know?

• Herpes cycles between periods of active disease followed by periods without symptoms.
• Transmission may still occur when symptoms are not present.
• Worldwide rates of either HSV-1 or HSV-2 are between 60% and 95% in adults.
• There is no available vaccine and once infected, there is no cure.