Herpes (Herpes Simplex Virus)

HSV-1 vs HSV-2

Both types cause identical sores, and either can infect either site. Herpes zoster (shingles) is caused by a different herpes virus, the chickenpox virus. See shingles.

How herpes spreads

• direct skin contact with the area where the virus is active, including kissing and oral, vaginal and anal sex
• asymptomatic shedding: the virus can be present on normal-looking skin, which is how most genital herpes is passed on
• from mother to baby during birth (neonatal herpes), most risky when the mother first catches herpes late in pregnancy

It is not spread through toilet seats, swimming pools or bedding.

Symptoms

First outbreak (primary infection)

The first episode, 2 to 12 days after exposure, is often the worst, though many people have no symptoms:

• tingling, itching or burning
• clusters of small fluid-filled blisters that burst into painful shallow ulcers, then crust and heal
• fever, aches, headache and swollen glands
• painful urination with genital herpes
• in young children, painful gums and mouth ulcers (herpetic gingivostomatitis)

Healing takes 2 to 4 weeks.

Recurrent outbreaks

After the first infection, HSV hides in nerve roots and can reactivate. Recurrences are usually milder, shorter (5 to 10 days) and in the same area. Many people notice warning signs (prodrome) such as tingling or burning a day before sores appear.

Triggers include stress, illness, fever, sunlight, menstruation, friction and a weakened immune system.

Other forms

• Cold sores: recurring blisters on the lip border.
• Genital herpes: sores on the penis, vulva, vagina, cervix, buttocks or anus.
• Herpetic whitlow: painful blisters on a finger.
• Herpes keratitis: eye infection that can scar the cornea.
• Eczema herpeticum: widespread infection over eczema, an emergency.
• Herpes encephalitis: rare, life-threatening brain infection.
• Neonatal herpes: serious infection in newborns.

Diagnosis

• PCR swab of a fresh sore: the most accurate test; tells HSV-1 from HSV-2
• blood antibody tests: show past infection with HSV-1 or HSV-2; useful in specific situations (such as a partner with herpes), but not recommended for routine screening because of false positives and limited usefulness
• examination by a clinician

Treatment

There is no cure, but antivirals work well.

For outbreaks

• acyclovir, valacyclovir or famciclovir tablets, started at the first tingle or within a day of sores appearing, shorten outbreaks
• first genital outbreaks are treated for 7 to 10 days
• cold sore creams (docosanol over the counter, or prescription antiviral creams) help a little if used very early

Suppressive therapy

Taking an antiviral every day:

• reduces outbreaks by 70 to 80 percent
• lowers the risk of passing genital herpes to a partner by about half
• is recommended late in pregnancy for those with genital herpes, to reduce outbreaks at delivery

Home care

• keep sores clean and dry; wear loose cotton underwear
• pain relief with acetaminophen (paracetamol) or ibuprofen, following the label dose
• for painful urination, pour warm water over the area while urinating or urinate in a warm bath
• lip balm with sunscreen to prevent sun-triggered cold sores
• do not touch sores; wash hands after applying creams

Reducing transmission

• avoid sex and kissing during outbreaks and while prodromal symptoms are present
• use condoms or dental dams consistently; they reduce but do not eliminate risk
• daily suppressive antivirals for the partner with herpes
• tell partners; many couples where one partner has herpes never transmit it
• do not perform oral sex during a cold sore

Living with herpes

A herpes diagnosis can be upsetting, but for most people it is a manageable skin condition. Outbreaks usually become less frequent and milder over time. Support groups, counseling and honest conversations with partners help.

Frequently asked questions

What is the difference between HSV-1 and HSV-2?

HSV-1 usually causes cold sores around the mouth and is often caught in childhood, but it causes a growing share of genital herpes through oral sex. HSV-2 mostly causes genital herpes and tends to recur more often. The sores look the same.

How do you know if you have herpes?

The typical sign is tingling followed by clusters of small blisters that turn into painful sores and heal in 1 to 2 weeks. Many people have no symptoms. A PCR swab of a fresh sore gives the most reliable diagnosis.

Can herpes be spread without symptoms?

Yes. The virus can be shed from normal-looking skin, and most genital herpes is passed on by people who have no visible sores or do not know they are infected. Daily antivirals and condoms reduce this risk.

Is there a cure for herpes?

No. The virus stays in the nerves for life. Antiviral medicines shorten outbreaks, reduce their frequency and lower the risk of passing herpes to partners. Over time, many people have fewer and milder outbreaks.

Is herpes dangerous?

For most healthy people herpes is a nuisance rather than a danger. It can be serious for newborns, people with weakened immune systems, and when it affects the eye or brain. Pregnant people with genital herpes should tell their care team.