Can You Get an STI From Kissing?

Kissing someone can be an incredibly exciting experience, especially if you’re kissing someone for the very first time.

The act of kissing is an expression of intimacy between partners. As a form of nonpenetrative sex, kissing is often considered a safer sex practice because it carries a much lower risk for sexually transmitted infections (STIs) and diseases (STDs) when compared to other activities like oral sex.

But when you participate in deep, or “French,” kissing where your tongues are touching and you’re exchanging saliva with your partner(s), there’s still some risk for the transmission of specific STIs.

Primary care physician and transgender medicine specialist Antonia “Nia” Nwankwo, MD, shares which STIs can be transmitted through kissing and which can’t, along with how to talk to your partner(s) about STI prevention.

STIs/STDs you can get from kissing

These are the most common STIs that can be spread by kissing:

Herpes simplex virus 1 and 2

The herpes simplex virus (HSV) is a common infection with a few variations that causes painful sores, blisters and ulcers.

HSV-1, or oral herpes, causes red or white cold sores to appear on or around your mouth. It’s estimated that, globally, 67% of people under the age of 50 already have this virus. You can get this virus by kissing when there are no symptoms present, touching or kissing an active cold sore, or sharing food utensils, lip balm or razors. It can also spread to your genitals if someone with the virus gives you oral sex.

HSV-2, or genital herpes, is typically transmitted through oral, genital or anal sex. But it can also be transmitted through mouth-to-mouth kissing especially if you and/or your partner(s) are also participating in oral sex.

“It’s kind of like bringing something up the elevator,” says Dr. Nwankwo. “You still have saliva and your mouth is still touching it. So, if you’re kissing someone after coming into contact with that virus, that virus can spread.”

HSV isn’t curable, but it tends to go dormant or become inactive for periods of time, during which it’s less likely for the virus to be transmitted (but still possible). When cold sores come up or flare-ups occur and the virus becomes more active, antiviral medications and topical ointments are available to help reduce flare-ups and the severity of your symptoms.

“At the time of the flare, we treat the flare, and then, you may not have to be on any medication after that,” explains Dr. Nwankwo. “Some individuals require medication daily to suppress chronic flares.”

Cytomegalovirus (CMV)

Cytomegalovirus (CMV) is a viral infection that you can get by having direct contact with body fluids that contain the virus, including:

• Saliva.
• Urine.
• Blood.
• Semen.
• Cervical secretions.
• Breast milk.
• Feces.

So, you can get CMV through kissing and the exchange of saliva. Because it can be transmitted in so many different ways, CMV isn’t usually considered an STI. But it can still be transmitted through oral, genital or anal sex.

Like herpes, CMV is a lifelong condition that gets treated with antiviral medications during flare-ups. Someone with CMV may never have symptoms, or you may experience occasional symptoms during a flare-up that include:

• Fever.
• Fatigue.
• Muscle aches.
• Sore throat.
• Swollen lymph nodes.

“If someone is immunosuppressed, they may experience more severe symptoms that include painful ulcers, lesions in the mouth, throat or esophagus, or you can have trouble swallowing,” says Dr. Nwankwo.

Epstein-Barr virus (EBV) and mononucleosis (mono)

The Epstein-Barr virus (EBV) is the leading cause behind the extremely contagious mononucleosis (mono), otherwise known as “the kissing disease.” Both EBV and mono spread easily through saliva and other body fluids by way of:

• Kissing.
• Sexual contact.
• Coughing or sneezing.
• Sharing toothbrushes, food, drinks and eating utensils or glasses.
• Blood transfusions.
• Organ transplants.

“This is one that people often get when they’re younger or in college and spending a lot of time in close quarters because you’re sharing cups and sharing tools,” notes Dr. Nwankwo. “If someone with EBV puts a pen in their mouth and you put that same pen in your mouth, you’ve opened up a risk for infection.”

For EBV, symptoms range in severity and often include swollen lymph nodes in your neck alongside other symptoms like:

• Sore throat and swelling.
• Fatigue.
• Fever.
• Rashes on your skin.
• Enlarged spleen and liver.

Mono presents the same symptoms in addition to muscle aches, headaches and loss of appetite. It may also take longer to recover from mono than EBV because mono may linger for longer periods.

Syphilis

Syphilis is an STI caused by a bacterial infection that generally spreads through oral, genital or anal sex. The bacteria that causes syphilis can enter your body through any of these activities, but it can also enter through broken skin (like cuts or scratches) or if you have direct physical contact with a syphilis sore or rash. That means If you kiss someone who has an active syphilis sore or cut in or on their mouth, or you kiss a part of someone’s body that has an active syphilis rash, you could pick up the syphilis infection.

“In the first stage of syphilis, known as primary syphilis, painless ulcers called chancres can appear in the mouth or on the lips up to three weeks after exposure,” explains Dr. Nwankwo.

“Deep kissing in high-risk areas lined in mucous like the mouth, genitals and rectum can increase transmission spreading through the bloodstream. Coming in contact with the skin has a low risk overall, but if a skin rash has broken or is leaking fluid, there is a bit more of a risk of passing through bodily fluids. Touching someone with an infection is also low risk, as the bacteria is not readily present on the skin.”

Syphilis is most often caught in its earliest stages when you’re most likely to notice pimple-like lesions or sores and rashes alongside other flu-like symptoms like fatigue, fever, sore throat and muscle aches. Once the infection becomes latent (meaning the physical symptoms disappear but you still have the infection inside your body), syphilis can cause dangerous complications. Over time, syphilis can do damage to your heart, brain, eyes and nervous system — so treating this infection with antibiotics early is key to avoiding these complications.

“Getting to a healthcare provider when you notice new sores on your body is important,” stresses Dr. Nwankwo. “Only you know what behaviors you have that may put you at increased risk for infection. Syphilis is treatable and long-term complications can be avoided.”

Human papillomavirus (HPV)

The human papillomavirus (HPV) is a complex common virus that can affect different parts of your body. With more than 200 strains and subtypes, HPV infections can lay dormant without ever causing any symptoms. That makes HPV even more dangerous, considering some strains can cause different kinds of cancer like anal cancer and cervical cancer if they remain in your body for longer periods of time. Notably, men who have sex with men (MSM) have a higher risk for HPV infections that can lead to rectal cancers.

About 40 strains of this virus can cause oral HPV, and nine of those strains can potentially turn into oropharyngeal cancer (cancer of the back of the throat). That’s why getting the HPV vaccine is so important for men and women regardless of your age.

“My dad always says a pound of prevention is better than an ounce of cure, and I live by this model daily,” shares Dr. Nwankwo. “Sexual health is health. So, getting vaccinated for STIs like HPV, annual screenings, condom use, and use of preventive medication are all a part of knowing your status.”

Most people with oral HPV don’t show symptoms, but some can develop oral lesions or sores on their lips or inside their mouth and throat. Like other strains of HPV, oral HPV can be transmitted through oral sex or mouth-to-mouth contact. It typically goes away on its own within a couple of years or can linger for longer.

Gonorrhea

Gonorrhea is another bacterial infection that, until recently, has always been considered an STI that’s transmitted through oral, genital or anal sex. But recent research suggests gonorrhea may also be spread through kissing.

A 2019 study out of Melbourne, Australia, surveyed 3,677 MSM over three months. The study found that those who participated in only kissing and kissing with other sexual activities had higher associations with oropharyngeal gonorrhea (gonorrhea of the throat) compared to those who only had sex without kissing.

A similar study from 2022 found that oropharyngeal gonorrhea was associated with an increase in kissing and “rimming” (analingus) partners, but not fellatio — suggesting that both kissing and rimming should be considered independent risk factors for the spread of gonorrhea.

Following this, a 2023 systematic review found four additional studies that supported these claims. Those researchers illustrated a variety of reasons why more research is needed to understand the direct connection between kissing and gonorrhea.

For starters, each of the studies was focused on MSM and conducted out of Australia. Future studies should be done in other cultures with a variety of populations to try and build on what these studies have published and see whether or not those same results can be replicated and confirmed.

Plus, researchers pointed out that most previous studies that looked into the transmission of gonorrhea may not have always accounted for kissing as a potential risk factor and, therefore, may not have always evaluated the transmission of gonorrhea effectively, particularly among certain populations that are often overlooked or underrepresented like the LGBTQIA+ community.

“We live in a time period where everything is not as it seems. With instant access to information and resources, we have the ability to hold ourselves accountable,” notes Dr. Nwankwo. “By being an advocate for yourself, you take up a power of knowledge. Know your body, get screened regularly for STIs, and know your provider, so when things pop you have some control over your story. Practicing safer sexual health often begins with communication, and keeping free-flowing communication open with your provider can lead to a better experience for you and overall better care.”

Mpox

Mpox is a rare disease that’s caused by a virus similar to smallpox. It’s transmitted in a few different ways:

• Humans can become infected by the virus through physical contact (like bites or scratches) with an infected wild animal or by eating infected animals when not cooked properly.
• Humans can infect other humans through close personal contact with someone who’s infected with the virus. Close contact includes sexual intercourse, skin-to-skin contact like cuddling or face-to-face contact like kissing. Breathing in close range of one another where respiratory droplets or saliva can be exchanged or make direct contact with someone’s skin can also spread the infection, according to the World Health Organization (WHO).
• The U.S. Centers for Disease Control and Prevention (CDC) says the virus that causes Mpox can also persist on surfaces like bedding, clothing, towels and other objects for up to 15 days. People may become infected with the virus if they come into contact with these objects where the virus persists, especially if they have an open wound or touch their face or other mucous membranes before washing their hands.

Recent outbreaks of Mpox have occurred, in large part, as a result of being transmitted through sexual contact. Researchers don’t know if the virus that causes Mpox can be transmitted through semen or cervical secretions. But studies show that there’s evidence the virus can be transmitted and detected in saliva and respiratory droplets. That means if you’re kissing someone who has Mpox, you’re at increased risk for infection — something both the CDC and WHO have an unequivocal stance on until more research is done.

“The highest group at-risk for Mpox are men assigned male at birth (AMAB) who have sex with men,” states Dr. Nwankwo. “Getting vaccinated is so important in helping to prevent the spread of rare diseases. Think of getting vaccinated not just for you but with protecting your partner(s) in mind.”

STIs/STDs that are NOT transmitted through kissing

Most STIs are transmitted through close contact with infected areas, most often on your genitals, and through other body fluids like semen, cervical secretions, discharge and blood. Only a few (like CMV, EBV and HSV) are transmitted through saliva.

That said, if you’re having oral sex in addition to kissing, your risk for STIs that are transmitted by other means increases unless you use barrier protection like condoms or dental dams. Even then, there’s still a risk for infection.

“If you or your partner decides to give oral sex, then those infections from down below can get passed up to our mouths,” clarifies Dr. Nwankwo. “There’s a lot less risk when it comes to relying on kissing as a safer sex practice, but there’s still an increased risk if you’re participating in other sexual activities.”

If you’re only kissing and not participating in any other oral sexual activity, you reduce the risk of transmitting these other common STIs that spread by other means:

• Chlamydia: This bacterial STI spreads through oral, genital and anal sex — not saliva. Infections can also occur if someone with chlamydia shares sexual toys with another partner.
• Hepatitis A, B and C: Hepatitis is inflammation of the liver and it can be caused by several things, including viral infections. EBV and CMV, for example, can lead to short-term hepatitis. When it comes to sexual transmission, hepatitis often spreads through sexual contact and blood but not saliva. Hepatitis A specifically can be spread through fecal-oral contact, making rimming an increased risk for hepatitis A.
• Pelvic inflammatory disease (PID): This bacterial infection directly impacts the uterus, fallopian tubes and/or ovaries in women and people assigned female at birth (AFAB). It’s caused by bacteria that enter into the reproductive system through the cervix, so this condition can’t be caused by kissing. Gonorrhea and chlamydia are common bacterial infections that cause PID when left untreated.
• HIV: Saliva can’t transmit this viral infection, so you can’t get HIV from kissing. The only way you can get HIV through mouth-to-mouth contact is if you and your kissing partner have open sores in your mouths or have bleeding gums, and blood carrying the infection gets into one of your open sores or wounds. Even then, transmitting HIV through mouth-to-mouth, mouth-to-broken skin or mouth-to-genital contact is rare.
  HIV enters your body through broken skin, your anus, penis or vagina and the infection is carried by these body fluids:
  
  - Blood.
  - Semen.
  - Cervical secretions.
  - Rectal fluids.
  - Breast milk.
  
  Importantly, if you’re HIV-negative and are taking PrEP (pre-exposure prophylaxis) or you have HIV and have an undetectable viral load, you can’t transmit HIV in either situation.
  “HIV has had so many advances in how we treat this disease that we now manage it like many other chronic diseases like diabetes,” explains Dr. Nwankwo. “There are medications, when taken appropriately, that prevent the transmission of the virus. Preventing others from becoming infected is a part of the cure.”
• Trichomoniasis: This parasitic infection is transmitted through oral, genital and anal sex, including vaginal-vaginal intercourse and genital skin-to-skin contact without ejaculation. This STI can’t be spread through saliva. It most commonly affects women and people AFAB but can affect men and people AMAB, too.
• Trichophyton mentagrophytes type VII: T. mentagrophytes is a common type of fungus that causes ringworm, athlete’s foot and jock itch. In a recent case study, researchers discovered that genotype VII is a specific type of this fungus that can be sexually transmitted through sexual intercourse (not kissing) and may be resistant to some antifungal medications.

How to talk to your partner about STIs and your status

STIs don’t have to be a tricky, taboo subject that makes us uncomfortable. STI prevention is dependent on having open and honest communication with your partners and participating in safer sex practices. If you’re not sure how to approach the topic of STIs with your partner, here are some strategies:

• Understand your own risk factors: Reflect on what you do, how you protect yourself, and the areas you want to work on to improve your safety and reduce your risk for infections. Recognizing your own sexual behaviors and the kinds of practices that support your safety allows you to establish better healthy boundaries and enter into a conversation with your partner(s) from a more personal perspective.
• Center the conversation around “I.” Use “I” statements by focusing on what you need and want in a sexual relationship in order to feel safe and satisfied, and what safer sex practices you participate in on your own. “If you say, ‘Hey, I always get tested every three months. Do you know your last testing status?’ that approach isn’t putting the blame on another person or making assumptions,” says Dr. Nwankwo. “You’re saying, ‘This is what I do for myself and I’m curious what you do for yourself,’ so it’s less charged and it doesn’t seem as judgmental.”
• Focus on the facts: If you have an STI or you’ve had a sexual history of STIs, that’s important information for your partner(s) to know — even if you’ve had treatment for that STI or that STI, like herpes, is currently inactive. Focusing on the facts is important when having this discussion. “You have to be able to protect yourself, and if you care about your partner(s), you’ll want to protect them, too, by letting them know,” urges Dr. Nwankwo. “Often, having this conversation comes with picking people that you want to be honest with and people you want to engage with. That increases the chances of you having the space to be that vulnerable.”
• Speak with empathy: If your partner shares their status with you and tells you they have an STI or a history of STIs, don’t be dismissive of that information or their lived experiences. “Thank people for sharing that information with you and let them know you’re grateful that they came to you with this information because it is hard and there is a lot of stigma we have to unlearn when it comes to STIs,” advises Dr. Nwankwo.
  “From there, you have a choice whether or not you want to continue engaging in sexual activity with this person. You can set up expectations, ask questions about any medications that are available that can prevent STIs or talk about other things you can do to protect yourself and each other going forward should you decide to continue engaging in sexual activity.”
• Embrace safer sex and other preventative practices: Get tested for STIs regularly, don’t share utensils like razors, toothbrushes or syringes, use condoms, and make an appointment with a healthcare provider when you experience new signs or symptoms of a possible infection.

Final thoughts?

“Kissing isn’t completely harmless, but making sure you have a pulse on your own sexual health is a start to a safe and hopefully enjoyable experience,” encourages Dr. Nwankwo. “Pay attention to your body and be observant of your partner(s) body. Keeping the lines of communication open so you may comfortably ask questions is very important to having a safer experience.”