Genital herpes is a sexually transmitted infection caused by the herpes simplex virus, and it can pass between people through vaginal, anal, or oral sex (NHS). The part that surprises most people is that it can spread even when nothing looks or feels wrong, outbreaks tend to come back after the first one, and antiviral medicines can shorten an outbreak or suppress recurrences. Those three facts are the core of what you need to act on.
What causes it, and how it actually spreads
Genital herpes is a herpes infection of the genitals caused by the herpes simplex virus, or HSV (Wikipedia). It is a virus with two types, and the infection is passed on through vaginal, anal and oral sex (NHS). That means the virus is not something you catch from surfaces or everyday contact; it moves through sexual skin-to-skin contact during the kinds of sex listed.
The condition that changes how you think about risk is asymptomatic shedding. Most people either have no symptoms or only mild ones and do not know they are infected (Wikipedia). Because those people can still pass the virus on, waiting for a visible blister before you take precautions misses a large share of transmission. The practical reading is that you cannot use “no symptoms right now” as proof of no risk, for yourself or a partner.
The outbreak pattern: first episode versus recurrences
When symptoms do appear, they typically include small blisters that break open to form painful ulcers, and flu-like symptoms such as fever, aching, or swollen lymph nodes may also occur (Wikipedia). Onset is typically around 4 days after exposure, with symptoms lasting up to 4 weeks (Wikipedia). That first episode is usually the worst one, which is why it is the one most likely to send someone looking for care.
Recurrences are the reason this is a long-term condition rather than a one-off illness. The virus stays in the body, and outbreaks can come back after that first episode. The pattern to plan around is that the initial outbreak is the most severe, later episodes tend to be milder, and the timing of a recurrence is not something you can schedule around. If you are deciding whether a new symptom needs attention, the first episode is the one that most clearly warrants it.
Treatment: what antivirals do and do not do
Antiviral medicines are the treatment that changes the course of an outbreak. They shorten an outbreak when it is already underway, and they can be used to suppress recurrences so they happen less often. That is the realistic promise: antivirals reduce the frequency and duration of outbreaks. They are not a cure and do not remove the virus from your body.
If you think you might have genital herpes, you can see a GP. They’ll probably refer you to a sexual health clinic if they think you might have genital herpes (NHS). Sexual health clinics treat problems with the genitals and urine system (NHS). That referral is the normal route rather than a sign that something is wrong. Going to a sexual health clinic directly is a reasonable first step if one is available to you.
Pregnancy: why it matters at delivery
Genital herpes matters in pregnancy mainly because of the delivery itself. The concern is passing the virus to the baby during birth. Is why a known history of genital herpes is something your maternity team needs to know about before you go into labour. That conversation lets them plan around the delivery rather than react to it.
Safety note: If you are pregnant or planning a pregnancy and you have genital herpes or think you may have been exposed, tell your maternity team early. The timing and management of delivery is a clinical decision, and it should be made with your care team rather than guessed at from a general article.
Reducing transmission: what actually lowers risk
You can lower the risk of passing genital herpes on, but you cannot drive it to zero. Two measures do most of the work: antiviral treatment and condom use. Antivirals suppress recurrences and reduce shedding, and condoms reduce skin-to-skin contact during sex. Neither one removes risk entirely, which is why they are used together rather than as alternatives.
- [ ] Tell a new partner that genital herpes can spread even when there are no symptoms.
- [ ] Use condoms for vaginal, anal, and oral sex, not only during outbreaks.
- [ ] Ask about daily antiviral suppression if you have frequent recurrences.
- [ ] Go to a sexual health clinic for testing and treatment rather than waiting for a blister to appear.
- Get tested at a sexual health clinic if you have symptoms or a known exposure.
- Start antiviral treatment early in an outbreak to shorten it.
- Ask whether daily suppressive antiviral therapy fits your recurrence pattern.
- Use condoms consistently, including when no symptoms are present.
- Tell partners about the asymptomatic shedding risk before sex, not after.
The stop boundary is simple: this page tells you what the condition is, how it spreads, how outbreaks behave, what treatment does, and how to reduce transmission. It does not replace a diagnosis or a treatment plan. For testing, treatment, or pregnancy planning, the destination is a sexual health clinic or your maternity team, and that is where the decisions that matter get made.