Bad News: Tongue Kissing May Transmit Gonorrhoea

We spoke to an Australian researcher who recently discovered that the STI can be spread through french kissing.

by Mark Wilding
13 May 2019, 11:42am

Neither of these people have gonorrhoea. Screenshot: VICE

If there’s one thing we all know about gonorrhoea, it’s that it is best avoided. But how is gonorrhoea actually transmitted? While safe sex messages tend to focus on intercourse, researchers in Australia recently published a British Medical Journal study of gay and bisexual men that found kissing with tongues could also pose a significant risk. We spoke to one of the study’s authors, Eric Chow, an associate professor at Monash University and a senior epidemiologist at the Melbourne Sexual Health Centre, to find out more.

VICE: Hi Eric. How worried should we all be about kissing?
Eric Chow:
It’s a really good question. I think we need more research. This is the first evidence that kissing may be transmitting gonorrhoea, but there are lots of things we need to know – like how people kiss, how long people kiss, how gonorrhoea is actually transmitted through kissing. So there are lots of research questions to be answered before we know the public health message. But definitely we know kissing may be contributing to gonorrhoea transmission.

Your study looked specifically at oropharyngeal gonorrhoea. What is that?
In men, gonorrhoea can infect the oropharynx – which we simply call the throat – the anus, and the urethra. This is similar in women, who can also get gonorrhoea in the throat and in the anus, but we don’t know the prevalence because we don’t usually screen women. In men, particularly for gay men, there’s a very high prevalence in the throat.

Most of the cases in the urethra are symptomatic; the typical symptom is urethral discharge so they will go to the clinic and get treated and it will be immediately actioned. That’s why we think it’s unlikely to get gonorrhoea from the urethral site; it’s going to be treated very quickly. The story for the throat and anus is a bit different because they are mostly asymptomatic, so people probably won’t know they have the infection at all.

What’s the key finding from your study?
Traditionally we thought someone got urethral gonorrhoea by having sexual intercourse, but no-one actually knows how people get it in the throat. There were some studies in the 1970s that suggested you can get gonorrhoea through kissing but there were no large modular studies showing this evidence. This is the first. We also teased out kissing from sex. We looked at kissing with sex and without sex, and we found that regardless of whether you have sex or not, kissing is a risk factor for throat gonorrhoea. People probably think it would be by having oral sex; someone will have an infected penis and then they will get infected in the throat. This study actually changed this concept. It’s not only from oral sex but you can also get it from kissing.

If this was suggested back in the 1970s, why has it taken so long for this to be tested?
You really need to tease out people who only kiss and we know in the gay and bisexual male population that kissing is very common during sex. It’s a difficult study to do and that may mean it took longer to do it.

Your study looked specifically at men who have sex with men who attended a sexual health clinic in Melbourne. Are your findings likely to be relevant to other groups?
In short, we don’t know. In Australia and in the UK we don’t recommend screening heterosexual men and women. This is because the prevalence is very low in the heterosexual population so we never screen asymptomatic patients. So we don’t really know the risks to other populations. Other research needs to be done for other populations such as heterosexuals or sex workers.

You note in the study that telling people to stop kissing could be a challenging public health message. What steps could be taken to prevent transmission?
Two years ago we did a survey and asked men who have sex with men if they would stop kissing to prevent gonorrhoea and most of them said no. And we know you can’t use condoms to prevent gonorrhoea through kissing. We published a paper about three years ago – a pilot study looking at 56 men who have sex with men – and there was definitely evidence showing mouthwash could be used for gonorrhoea prevention. We’re now doing a large clinical trial in Melbourne and in Sydney on more than 500 men who have sex with men. The trial is now complete and we’re finalising the results, so we’ll hopefully have some finding some time this year. If it works it would be a really good and simple prevention for gonorrhoea.

So do you hope there might be a public health campaign promoting this?
That’s what we’re thinking. We also asked people previously and found that they’re very happy to use mouthwash for gonorrhoea prevention. It’s so easy, you can just get it from the supermarket or pharmacy and you can just do it routinely as part of your dental care. We think it will be quite effective and quite an easy public health message to roll out.


sexual health
sexually transmitted infections