Most public health campaigns about preventing the spread of throat gonorrhoea focus on genitals but Australian researchers have found the infection can spread via "deep kissing".
"We interviewed more than 3,000 gay and bisexual men at the Melbourne Sexual Health Centre and found that kissing is associated with throat gonorrhoea," Melbourne epidemiologist and co-author of the study Eric Chow told BuzzFeed News.
Published today in Sexually Transmitted Infections, an official journal of the British Association of Sexual Health and HIV, the study shows the first empiric evidence that gonorrhoea may be transmitted from one man’s throat to another man’s throat through tongue-kissing.
Previously, it had generally been assumed that oropharyngeal gonorrhoea could only be acquired from an infected penis or anus, not from another man’s oropharynx (the part of the throat at the back of the mouth behind the oral cavity).
Chow said the results suggest kissing with or without sex may be a risk factor for the infection, but that it has to be significantly more than a peck on the cheek.
"There needs to be enough time to have saliva exchange between the individuals," he said. "Like a French kiss."
Strains of gonorrhoea that are resistant to antibiotics are becoming more common in many countries, sparking concerns the infection will become increasingly difficult to treat.
"We are running out of antibiotics to treat it," Chow said. "There are cases of antibiotic resistant gonorrhoea not only in Australia but globally it is emerging as a public health issue as it could become untreatable."
Gonorrhoea can be transmitted through anal, vaginal or oral sex, even when there are no symptoms.
Gonorrhoea can infect the throat, anus, urethra, cervix and eyes. It can be diagnosed via a urine sample or swab from the infected area and is treated with antibiotics.
While public health campaigns to curb the spread of throat gonorrhoea among gay and bisexual men have focused on promoting condom use, Chow said the study might open up other preventive options such as antibacterial mouthwash.
"If you can get [throat] gonorrhoea from kissing without having sex it means even if you use a condom you might not be protected against it," he said.
"We are doing a clinical trial in Melbourne and Sydney [for which we have] recruited 500 gay and bisexual men to look at the effectiveness of daily mouthwash in preventing gonorrhoea."