Condyloma (wart) in the mouth

Human papilloma virus (HPV) is the virus that causes most cervical, vaginal, and anal cancers. It also causes cancer of the vulva, and penis. More recently, HPV has been identified as an increasing cause of head and neck cancers, especially for men. From 1984 to 2004 the percentage of head and neck cancers related to HPV jumped from 16% to 70%.

While there are more than a 100 types of HPV, there are several strains (HPV 16 and HPV 18 in particular) that are particularly cancer causing both above or below the belt.

HPV is ubiquitous in the genital tract. If you are a woman and you are sexually active there is a 70% chance you will have been infected by the age of 22. The good news is most people clear their HPV infection. It’s the infections that the immune system can’t clear that are at risk of progressing to disease (either cancer or genital warts, the other manifestation of genital HPV infection). Regardless, while your body is working to get the infection under control you can spread the virus through sexual contact.

So what about the mouth?

We know oral sex is a risk factor for HPV-related head and neck cancers. If you have had oral sex with 6 or more partners your risk of head and neck cancer increases 8-fold.

A study just published in JAMA (Gillison et al, January 26, 2012) evaluated more than 5,000 people for oral HPV. They collected a lot of demographic data to try to determine risk factors.

The results:

  • 6.9% of people ages 14-69 have an active HPV in their mouth
  • The peak prevalence of oral HPV infection is ages 30-34 and 60-64
  • Men are more likely to have oral HPV than women (10.1% vs. 3.6%)
  • Sexual contact is a risk factor for oral HPV: 0.9% of people who have never had sexual contact had HPV versus 7.5% who had ever been sexually active.
  • The number of oral sex partners has a big effect on oral HPV. The prevalence is basically the same for 0 or 1 oral sex partner (3.5% and 3.3% respectively), but by the time you hit 21 or more sexual partners the prevalence of oral HPV jumps to 21.5%
HPV Prevalence by # lifetime oral sex partners

So what about kissing? (Sometimes when I pull these studies I think, gosh, I’d just rather not know…).

To me, the data in the JAMA study suggests oral sex is not the only method of transmission because 0.7% of those had never been sexually active at all and 3.5% of those who said they had never had oral sex were HPV positive. I suppose it’s possible that participants weren’t completely honest about whether they had engaged in sex or oral sex, but the study used NHANES participants and the data is generally high quality. So if oral sex wasn’t involved in transmission for the non sexually active/non oral sexually active participants, well, what was?

The studies are sparse. One small study looking at men only, published in 2009 (Journal of Infectious Diseases), tells us that for men “open mouth kissing” with 10 or more partners is associated with an increased prevalence of oral HPV. It’s not a huge study and it has limitations, but, well, there you have it. By no means am I saying that open mouth kissing is a major route for oral HPV transmission, but it definitely suggests we need more studies.

Whether the HPV vaccine will help with prevention of oral HPV remains to be seen; however, the editorial that accompanied the JAMA article pointed out that in an animal study a HPV vaccine was able to prevent oral infections. In addition, fewer genital infections (due to vaccination) should translate into fewer oral infections given the known oral sex connection.

Why are we seeing more HPV-related head and neck cancers? I have a hard time accepting it’s all oral sex, since I’m pretty sure oral sex wasn’t invented in the last 20-30 years. Although, studies suggest there is more oral sex happening earlier (20% of kids in grade 9 have tried oral sex!), so perhaps adolescence is a more vulnerable time for oral HPV exposure. Smoking was also major cause of head and neck cancer and there are fewer smoking related cancers, so percentage wise HPV is now a bigger player. It is also possible other environmental co-factors are involved. Again, more studies are needed.

What we know for sure:

The more oral sex partners you have, the more likely you are to get HPV in the mouth. Like genital infections, most oral HPV will clear, but persistent infections increase your risk of head and neck cancer. Seventy percent of head and neck cancers in men are now HPV related.

Where STDs are concerned, fewer partners is safer. If you are going to have multiple oral sex partners, use a barrier method. Studies are conflicting about their effectiveness, but some protection is better than no protection.

The HPV vaccine reduces your chance of having cervical and anal cancers.

And while oral sex might not get you pregnant, it should be considered sex because it certainly has all the same infection related risks.

Related posts:

How many sex partners do people really have?

Can I get gonorrhea from oral sex?

The oral sex-oral cancer connection

Join the Conversation

50 Comments

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

  1. Excellent reading dr jen ..many thanks fir your studys ..im in for a biopsy soon on my vocal cords as the ent dept has seen white on my cords ..
    Ive noticed a change the past few months as my voice is getting horse and if i cough im.barking liyd like a dog .
    After the scope up my nose and tge consultant checking ive been told i need a biopsy ..can you help …what are the chances of this being a a hpv? Or cancer ??many thanks gary uk

  2. Here all information’s are very useful to everyone.I think these are really some of the important tips that you have shared. I definitely enjoyed every little bit of it. Thanks for sharing this valuble information.

  3. If a girl had suffer with genital HPV and a man kiss her on lips so is it possible to transmit HPV to that man without have any sex?

  4. At my last yearly gyn exam my doctor suggested I also get tested for HPV. I have been widowed since ’96 and had not had sex since my husband died. I never had sex with anyone but my husband. I scoffed when my dr. suggested this but he said if I remain celibate I’ll only need to get a pap smear every 3 years. The pap was normal and negative for HPV. My question is, is HPV negative for my whole body or just for my privates?

    1. I have been with my current partner (woman) for the last 10years and in that time, I have been totally faithfull, she says that she has been totally faithfull during this time also. I am her third partner, the first being her husband for 14years, (he did go with other women during therir time together) her second partner was for some 15months, this person went with any woman that he could, but not apparently while they were together! I have had numerous women partners since my divorce 12years ago, (my ex-wife had genital warts and blamed me for them! I had not been with any other woman during our time together, but have lately found out, that she had been with other men!).
      I have never suffered any sexual dieases at all, and as I said earlier in this post, have only been with my current partner since we got together 10 years ago, but no she has a white-headed wart on her inside bottom lip, she has been to doctors and he has referred her to specialist in local hospital, how can this have occurred!!! I am at a loss, I want to believe what she say’s but after finding out about my ex-wife, I am worried that she may be lying to me!!

      1. maybe you just have strong immune system, usually male does, specially when it comes to HPV, and maybe you have virus in you for years (even more than 10), and not knowing that
        in that case, you have no symptoms, but you female partner does,
        maybe you collected that from your ex-wife

        (sorry for my english 🙂

  5. Thanks for highlighting this research. I’m involved in studies investigating transmission of oral HPV and the role of other environmental co-factors…so hopefully we’ll have more useful information soon.

    In terms of the kissing hypothesis (i.e. the individuals with oral HPV without ever reporting having sex (or oral sex)) there are a few hypotheses among the skeptics:
    1. Since the studies rely on self-report, some individuals could be misreporting their sexual behavior. (you touched on this one)
    2. vertical transmission at birth – there are a few papers suggesting very young children (age 1-4) have oral HPV – so it’s possible they had the virus since birth
    3. self-inoculation. there’s evidence that people can have HPV on their fingertips, which could be transferred to the mouth..though i’m a bit skeptical.

    Overall, I think it’s feasible that virus could be transmitted through kissing, but if it does it probably only happens in rare cases…considering the relatively low prevalence of oral HPV compared to genital HPV. (though we’ll have longitudinal studies hopefully soon to get a better feel for the clearance of oral HPV, etc).

    One final point – be careful when using that 70% of head and neck cancers stat. There’s evidence that HPV causes 70% of oropharyngeal cancers, which is a type of head and neck cancer. However there are other types of cancers in the oral cavity (lips, tongue, etc) that are more common and still considered “head and neck cancer”. So I’d say HPV causes 25-30% of head and neck cancers overall. Also – while these cancers have been increasing, they are still relatively rare. So I think there is valid debate on whether individuals should change their behavior based on this evidence alone.

    1. I’m not sold on vertical transmission producing a low grade viral infection for 20 years. Given 30% of babies are born by c-section and the c-section rate skyrocketed in the past 20 years we should be seeing less oral HPV if vertical transmission were a major factor. Say vertical transmission did happen, that would only be the 0.7% who claim to never have had sex (i.e. that would be the baseline risk, doesn’t explain the oral HPV in the people who never had oral sex). More likely would be kissing from parents etc. Toddlers are awfully sloppy with their kisses (mine were anyway).

      I got the 70% from this editorial in the NEJM http://www.nejm.org/doi/full/10.1056/NEJMra0707975 which reported. “HPV DNA was detected in 72% of 100 oropharyngeal tumor specimens, and 64% of the patients in the study were seropositive for HPV-16 E6, HPV-16 E7, or both.”

      I could have been more precise by not using the term head and neck cancer and sticking with oral/mouth and throat, so point well taken.

      Thanks for your insightful comments!

      1. Yea, I don’t think vertical transmission would be a major factor either. However, it could potentially explain the few oral HPV infections we see in virgins, if individuals couldn’t transmit through kissing. The paper I’m thinking of shows that the prevalence of oral HPV is 2.5% for children <1 yr, 0.8% for children 1-4yr, and then slowly increases as children reach adolescence. (see here: http://www.ncbi.nlm.nih.gov/pubmed/17721381) It's also possible that it's just kissing from the parents or relatives…I think it'd be hard to tease that out.

      2. C-sections don’t prevent transmission from mother to child. The virus is present in the amniotic fluid.

%d bloggers like this: