HSV-1 versus HSV-2 — what is the difference?
HSV-1 traditionally causes oral herpes (cold sores around the mouth) and is typically acquired in childhood through non-sexual contact. HSV-2 traditionally causes genital herpes and is usually transmitted through sexual contact. However, HSV-1 now accounts for a significant proportion of genital herpes, particularly among younger people — primarily through oral sex. Both types can establish a latent infection in nerve tissue and reactivate as outbreaks.
Symptoms and outbreaks
The first outbreak (primary infection) is often the most severe, and may cause painful blisters or ulcers, flu-like symptoms, and swollen glands. Many first infections are so mild they go unnoticed. Recurrent outbreaks are typically shorter and less severe. Warning signs (tingling, itching, burning) often precede an outbreak. Frequency varies enormously — some people have only one outbreak ever; others have several per year.
How herpes is transmitted
Herpes is transmitted through direct skin-to-skin contact with an infected area. This includes genital contact, oral sex, and kissing. Transmission can occur even when there are no visible sores, due to asymptomatic viral shedding. Condoms significantly reduce (but do not eliminate) the risk. Antiviral suppressive therapy in the infected partner further reduces transmission risk by around 50%.
Herpes testing
During an active outbreak, herpes is best diagnosed by swabbing a blister or sore for viral PCR. Blood tests (serology) detect HSV antibodies but are most accurate 12–16 weeks after exposure. Routine blood testing for herpes is not recommended in people without symptoms, as the results can cause anxiety without changing management. The NHS does not routinely offer herpes blood tests; however, they are available privately.
Treatment and management
Antiviral medications — aciclovir, valaciclovir, and famciclovir — do not eliminate the virus but reduce outbreak frequency, severity, and duration. Suppressive therapy (daily antivirals) is an option for people with frequent outbreaks or who want to reduce transmission risk to a partner. Starting antivirals at the first sign of an outbreak (tingling stage) can abort or shorten the episode.
Living with herpes
A herpes diagnosis can feel overwhelming, but for most people it becomes a manageable part of life. Many people in long-term relationships with a herpes-positive partner never acquire the infection. Open communication, understanding of transmission risk, and available medical options allow most people to maintain fulfilling relationships. Support is available from healthcare providers and specialist sexual health services.