Sexpert: April 19, 2012

Dear Sexpert,

What STDs can I get from kissing?

— Freaked About Frenching

Dear Freaked,

Before I address your very interesting question, which is one that I get pretty frequently, a quick word about terminology. You use the phrase STDs, short for sexually transmitted diseases, a term that is very popular and probably still the most commonly used name for health conditions spread through sexual conduct, but you might also be aware of the more recent trend of people calling those conditions STIs, or sexually transmitted infections.

The meanings of STI and STD are similar but not identical. To put it briefly, an infection is when some foreign organism, like a virus, bacterium or fungus, colonizes your body. “Disease” refers to the negative health consequences, symptoms or effects, that are produced by that infection. The difference is worth remembering. One of the most important developments in public health during the last few years — the development of the HPV vaccine — involves a very common sexually transmitted infection that does not always lead to a disease.

The Human Papilloma Virus (HPV) is so common that the Centers for Disease Control and Prevention estimate that more than 50 percent of sexually active people will contract it in the course of their lives, and it can cause cancers of the mouth, throat, penis, cervix, vagina and anus. However, the vast majority of HPV infections never result in cancer. So while a significant portion of the population may have the sexually transmitted infection HPV, few will develop the disease cancer.

But, to answer your question, it is very unlikely that you will catch an STI from kissing. The risk of contracting HIV, the virus that causes AIDS, from kissing someone who is HIV-positive is virtually zero. Saliva is a remarkably poor medium for transmitting HIV. However, blood, as you may know, is an efficient carrier for the virus, so you might consider avoiding a kiss with someone who has an open cut in their mouth, especially if you have one too.

A sore is another indication that you might want to skip the kiss, since a herpes infection is likely to be contagious during an outbreak. According to Columbia’s excellent health site Go Ask Alice!, it’s possible for hepatitis B and bacterial meningitis to spread during a make-out session. I’ve told you what infections can possibly be passed through kissing, but let me tell you which ones are most probable: influenza, the common cold and mononucleosis. We don’t often think of these illnesses as sexually transmitted, but sex — and kissing in particular — can spread them even more easily than a germy doorknob. If you feel sick after kissing someone, chances are you’re just coming down with a cold.

— The Sexpert

Interested in Sexual Health? The Sexpert is always looking for passionate members of the community to join the team of sexual health educators who, along with fact-checking from University health professionals, help write these columns. Email sexpert@dailyprincetonian.com for more information, and, of course, with your questions about sexual health. Don’t be shy!