"Tongue kissing" may be an overlooked risk factor for transmission of throat gonorrhea, among men who have sex with men, researchers found.
Men with four or more kissing-only partners had a higher risk of having oropharyngeal gonorrhea, with similar risks seen for men with four or more kissing-and-sex partners
However, the number of sex-only partners (without kissing) was not a risk factor for oropharyngeal gonorrhea, the authors wrote in Sexually Transmitted Infections.
They noted that while most gonorrhea infections in this population occur through anal sex, recent prior research indicated that transmission of gonorrhea through the oropharynx is more common than previously thought. Neisseria gonorrhoeae was cultured from saliva, with the authors noting that both oro-anal contact (rimming) and saliva use for lubrication during anal sex are risk factors for anal gonorrhea. With "tongue-kissing" involving an exchange of saliva, gonorrhea could potentially be transmitted that way, the authors said.
"It has been proposed that [gonorrhea] can be transmitted through kissing, but kissing has always been neglected as a risk factor for [gonorrhea] transmission," they wrote.
Researchers examined data from MSM attending a public sexual health center in Melbourne from March 2016 to February 2017. Participants were boys and men ages 16 and up who had either kissed or had sex with a male partner in the last 3 months and were tested for oropharyngeal gonorrhea on that day. They were invited to complete a "Kissing" survey, which asked the number of male partners men had for:
Overall, 3,677 responses were included from 3,091 MSM, with a median age of 30. Around 3% had previously been diagnosed with HIV. There were about 6% of men who tested positive for oropharyngeal gonorrhea, about 6% for anorectal gonorrhea, and around 3% for urethral gonorrhea. There were 52 men with kissing-only partners, and 95 men with sex-only partners.
Notably, the authors found that a significantly lower proportion of men who only had sex-only partners tested positive for oropharyngeal gonorrhea than those who only had kissing-only partners (3% vs 6%, respectively, P=0.020).
They noted that "younger men kiss more sexual partners than older men" and added that "potential interventions such as antiseptic mouthwash, if shown to be effective against oropharyngeal [gonorrhea], could provide a non-condom and non-antibiotic-based intervention for [gonorrhea] control." This is particularly important, given "known challenges" in antimicrobial treatment of oropharyngeal gonorrhea, they said.
Limitations to the study include selection bias, due to the fact that it was at a single urban sexual health center, and that about 60% of MSM declined to participate in the "Kissing" survey, which could have had an impact on the results.