Worried you might have picked up a sexually transmitted infection from kissing? You’re not alone.
After a new encounter, many people ask, “Can you get an STD from kissing?”
The short answer is that kissing is generally very low risk for sexually transmitted infections (STIs). Oral herpes is the main STI associated with kissing, while syphilis can occasionally spread through contact with an infectious mouth sore.
In this guide, we’ll keep things simple and clear:
- What you can catch from kissing
- What you can’t catch from kissing
- When it’s worth paying attention
- What symptoms to look for
- What to do if you’re unsure
Other infections, including cytomegalovirus and Epstein-Barr virus, can pass through saliva, although they are not normally classed as STIs. Chlamydia and HIV are not spread through kissing, and UK guidance does not consider kissing a normal route for gonorrhoea.
Which Infections Can Kissing Spread?
| Infection | Can it spread through kissing? | What creates the risk? |
| Oral herpes (HSV-1) | Yes | Direct contact with infected skin, particularly an active cold sore |
| Syphilis | Possible, but uncommon | Direct contact with an infectious sore in or around the mouth |
| Oral HPV | Uncertain | Evidence about deep kissing is limited and conflicting |
| Cytomegalovirus (CMV) | Yes | Contact with infected saliva and other bodily fluids |
| Epstein-Barr virus (EBV) | Yes | Saliva, including kissing and sharing drinks or utensils |
| Chlamydia | No | Usually spread through vaginal, anal or oral sex |
| Gonorrhoea | Not considered a normal route | Usually spread through vaginal, anal or oral sex |
| HIV | No | Kissing and saliva do not transmit HIV |
| Hepatitis B or C | No | These infections are not spread through ordinary kissing |
What STDs Can You Get From Kissing?
Herpes Simplex Virus
Many people ask, “Can you get herpes from kissing?” Oral herpes, which is usually caused by the herpes virus herpes simplex virus type 1 (HSV-1), can spread through direct skin-to-skin contact and can therefore be passed on by a kiss. The risk is highest when someone has a cold sore, blister or ulcer around their mouth.
HSV-1 is a common infection. The World Health Organization estimates that around 3.8 billion people under 50, or 64% of that global age group, have HSV-1. It estimates that 520 million people aged 15 to 49 have HSV-2, the type more commonly associated with genital herpes and typically transmitted through sexual contact.
Herpes spreads most easily when someone has symptoms, but the virus can still spread when a person is not experiencing symptoms, including through asymptomatic shedding. Once contracted, the virus remains in the body and may stay dormant for long periods.
The NHS advises avoiding kissing and oral sex from the first tingling sensation until a cold sore has completely healed, and antiviral medications may be used to help manage outbreaks. Oral sex during this period can pass HSV-1 to a partner’s genitals, but genital herpes is not acquired from kissing alone.
Syphilis
Syphilis is a bacterial infection. While you can catch syphilis from kissing, it is uncommon and the risk is higher when there are visible sores on the lips or inside the mouth.
This sore, called a chancre, is often painless and may go unnoticed, though a broken sore or one leaking fluid may slightly increase exposure risk. Syphilis is not passed simply because saliva is exchanged.
The NHS guidance on syphilis identifies vaginal, anal and oral sex as the main routes, but confirms that contact with an ulcer inside the mouth can transmit it. Arrange an assessment if a partner has syphilis or you develop an unexplained painless ulcer, because syphilis left untreated can lead to serious complications.
HPV
Some types of Human Papillomavirus (HPV) can cause hpv infections in the mouth or throat. Research into transmission through deep or open-mouthed kissing is limited and conflicting. Oral HPV is better understood in the context of sexual activity than kissing alone.
Oral sex and intimate skin-to-skin sexual contact are better-established routes. HPV transmission through kissing is therefore possible but unproven, rather than a common or clearly defined risk. There is no routine oral HPV screening test for someone without symptoms.
Cytomegalovirus
Cytomegalovirus (CMV) is a common viral infection that often spreads through close contact with infected bodily fluids, including saliva. Kissing can therefore transmit CMV.
Most healthy people have no symptoms or only mild fever, tiredness, sore throat or swollen glands. CMV can be more significant during pregnancy or for people with a weakened immune system, who may develop more severe symptoms and should seek advice if concerned. CMV can remain active and transmissible for years.
CMV is not usually classed as an STI because it also spreads in several non-sexual ways, such as through breast milk.
Epstein-Barr Virus
Epstein-Barr virus (EBV), often called the kissing disease, is highly contagious and can cause glandular fever. It is commonly transmitted through saliva, including by kissing or sharing drinks, food, toothbrushes, or eating utensils.
It may spread before symptoms develop, as the initial infection can occur before symptoms appear, and remain in saliva for months after illness. NHS guidance on glandular fever lists fever, sore throat, swollen glands and extreme tiredness among the symptoms. EBV is not normally classed as an STI.
Can STDs Be Transmitted Through Saliva?
Some infections can be transmitted through saliva, but most common STIs are usually spread by genital fluids rather than kissing. “Through saliva” and “through kissing” do not always mean the same thing.
CMV and EBV can spread through saliva. Oral herpes can spread during kissing, but infected skin or a cold sore is the main concern. Syphilis requires contact with a sore. Saliva does not transmit HIV, chlamydia or hepatitis C. Gonorrhoea can infect the throat after oral sex, but concerns in research are more about oropharyngeal gonorrhea than ordinary kissing as a usual route, and kissing is not regarded in UK guidance as a usual route.
How Likely Is It To Get an STD from Kissing?
In most cases, the risk is very low, but there is increased risk in specific situations. A brief kiss where neither person has a visible cold sore or mouth ulcer is unlikely to transmit an STI.
The infection and type of contact matter more than the amount of saliva. An active herpes cold sore creates a clear risk, while direct contact with an oral syphilis sore can transmit syphilis. Deep kissing does not make chlamydia or HIV transmissible through saliva.
Concern is more justified when a partner has a known infection, an active lesion, or when kissing formed part of wider sexual contact, because the risk is increased in those situations.
What STDs Can’t Be Spread Through Kissing?
Can You Get Chlamydia From Kissing?
No. Chlamydia is not spread through kissing or saliva. It is primarily passed through vaginal, anal or oral sex and can infect the genitals, rectum or throat.
If oral or penetrative sex also occurred, testing should be based on those activities rather than the kiss.
Can You Get HIV From Kissing?
No. NHS guidance states that HIV cannot be acquired through kissing. Saliva does not transmit the virus.
If an encounter involved a significant blood exposure because of an injury, seek medical advice about the blood exposure itself. That is different from HIV being transmitted through saliva or an ordinary kiss.
Can You Get Gonorrhoea From Kissing?
Gonorrhoea is normally passed through vaginal, anal or oral sex. UK sexual health guidance does not consider kissing, including kissing someone with throat gonorrhoea, a usual transmission route.
Research continues, but evidence is not strong enough to treat kissing alone as established transmission. If oral sex also took place, a throat swab may be appropriate.
What About Hepatitis?
Hepatitis A, B and C are not spread through ordinary kissing. Hepatitis A is mainly passed through the faecal-oral route, hepatitis B through infected blood and certain bodily fluids, and hepatitis C primarily through blood.
When Does Kissing Become Risky?
Kissing is generally safe, but more caution is sensible when there is:
- An active cold sore, blister or tingling that suggests one is developing
- A visible or unexplained ulcer or other visible sores in or around the mouth
- Direct contact with a known syphilis sore
- Cuts or bleeding that create genuine blood-to-blood contact
- Deep or prolonged kissing when an infectious oral lesion is present
- Kissing as part of broader sexual activity, including oral sex
Risk is higher with open sores, bleeding, or direct contact with infectious lesions.
Recent dental work or bleeding gums do not make saliva transmit HIV or chlamydia. However, broken skin can make direct exposure to blood or an infectious lesion more concerning.
How To Reduce The Risk When Kissing
You don’t need to avoid kissing completely; you just need to be aware of the warning signs.
- Avoid kissing from the first sign of a cold sore until it has completely healed.
- Do not share lip balm, drinks, cutlery or toothbrushes during an oral herpes or glandular fever infection.
- Avoid direct contact with unexplained sores or ulcers around a partner’s mouth.
- Talk openly with partners about known infections and current symptoms.
- Use barrier protection, such as condoms or dental dams, to reduce risks during oral sex; it is not relevant to kissing itself.
- To prevent STIs after a relevant exposure, get tested and discuss any concerns with partners.
- Seek advice if either person is pregnant, immunocompromised or concerned about CMV exposure.
Good oral hygiene cannot prevent herpes or syphilis if contact with an infectious sore occurs.
STD from Kissing Symptoms
If you’re worried after kissing someone, symptoms vary depending on the infection. Signs to look out for can include:
- Tingling, itching or burning around the lips
- Small fluid-filled blisters or cold sores
- A painless or unusual ulcer in or around the mouth
- Sore throat
- Swollen glands
- Fever
- Marked tiredness or fatigue
- A new rash alongside other symptoms
Timing varies. Herpes symptoms may develop relatively soon, while glandular fever or syphilis can take weeks. Some infections cause no noticeable symptoms, while others can cause severe symptoms, especially in vulnerable people.
A common mouth ulcer, spot or sore throat does not automatically mean an STI. Persistent or unexplained symptoms should be professionally assessed.
When Should You Get Checked?
Kissing alone does not usually require a standard STI screen. Testing or an examination may be appropriate if:
- You develop a new blister, cold sore or unexplained mouth ulcer
- You had direct contact with a partner’s confirmed herpes or syphilis sore
- A partner tells you that they have been diagnosed with an infection
- The encounter also included oral, vaginal or anal sex
- You are pregnant or have a weakened immune system and are concerned about CMV
- Symptoms are persistent, severe or getting worse
- You want individual advice and reassurance
- If you are sexually active, regular STI testing is a sensible way to stay safe, even though kissing alone usually does not require screening
The right test depends on the suspected infection and timing. Herpes is usually assessed by swabbing a fresh blister or sore, while syphilis generally requires a blood test. CMV and EBV are not included in every routine STI screen.
If you’re in London, you can arrange private STD testing with quick, discreet results, or speak to a healthcare provider about the right test and timing.
Want Peace of Mind? Here’s What to Do Next
At Broadgate GP, you can book a discreet appointment to discuss the contact, symptoms and whether testing is needed. Results may be available within 24 hours depending on the infection and test.
Our clinicians can examine oral symptoms, recommend suitable tests and arrange treatment. Book a confidential appointment for individual advice.
FAQs
Can you get an STD from kissing someone with no symptoms?
Yes, but the overall risk is low. Oral herpes can occasionally spread without a visible cold sore through asymptomatic shedding, although transmission is more likely with an active blister, ulcer or tingling sensation.
Can you get an STI from kissing if there’s no cold sore?
It is possible, but uncommon. Oral herpes may spread without visible symptoms, and an unnoticed syphilis sore could create a risk. CMV and EBV can also spread through close contact and saliva. Chlamydia, HIV and hepatitis C do not spread through kissing.
Is deep kissing more risky than a quick kiss?
Deep kissing may increase contact with unnoticed oral lesions, but the overall risk remains low. An active cold sore or syphilis ulcer matters more than the kiss’s length.
Can you get genital herpes from kissing?
Not from kissing alone. However, someone with oral herpes can pass HSV-1 to a partner’s genitals through oral sex. Avoid kissing and oral sex from the first cold sore warning signs until it has healed.
Can you catch chlamydia from kissing?
No. Chlamydia is not transmitted through kissing or saliva. Testing may be appropriate if oral, vaginal or anal sex also occurred.
What should I do if I kissed someone with a cold sore?
Watch for tingling, burning, blisters or sores and avoid kissing if symptoms develop. A fresh blister can be swabbed. People with cold sores must not kiss newborn babies, as neonatal herpes can be dangerous.
What should I do if I’m worried after kissing someone?
Consider whether there was a visible sore, confirmed infection, or risk of other STIs from contact beyond kissing. Monitor for symptoms and seek individual advice if concerned.
How long after kissing would symptoms appear?
It depends on the infection. Herpes symptoms may appear within days, while glandular fever or syphilis can take weeks. Timing alone cannot confirm or rule out infection.
Can kissing cause long-term complications?
Long-term complications from kissing are very unlikely. Oral herpes can cause recurring cold sores, untreated syphilis can become serious, and CMV matters more during pregnancy or weakened immunity. Seek advice for concerning symptoms or direct contact with an infectious sore.
This article provides general information and does not replace individual medical advice, diagnosis or treatment.
