Kissing with the tongue (or "French kissing") can transmit throat gonorrhea, according to a May 2019 study including gay and bisexual men.

Researchers believe throat gonorrhea has contributed to the global rise in gonorrhea infections.

Previously, experts believed gonorrhea mainly spread due to oral or vaginal sex.

Preventing the risk of throat gonorrhea is difficult because kissing is so common and symptoms can be hard to detect or mistaken for other conditions.

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Gonorrhea is generally known as an infection that spreads through sex, but there's now evidence the STI can spread from French kissing, too.

Researchers are warning people about throat gonorrhea specifically, since they believe this type of STI has greatly contributed to the global rise in gonorrhea infections. In 2016, 87 million people diagnosed with gonorrhea, according to a Wednesday press release.

In a May 2019 study in "Sexually Transmitted Infections" that was done by the same research team, kissing that uses the tongue (or "French kissing") could result in the spread of throat gonorrhea, a bacterial STI that can cause a sore throat, fever, and swollen lymph nodes.

The study specifically looked at men who identify as bisexual or gay. Researchers surveyed 3,091 men in their 20s and 30s who had been to a public sexual health center in Melbourne, Australia, asking them to disclose the number of male partners they had over the past three months and the sexual activities they participated in: kissing, sex without kissing, or sex with kissing. Sex was defined as oral or anal sex.

Researchers found that the men who reported only kissing or sex with kissing had higher instances of throat gonorrhea than men who only reported sex without kissing.

Of the 52 men who reported having kissing-only partners, 3.8% had throat gonorrhea, whereas 3.2% of men who reported having sex-without-kissing partners (95 men) had throat gonorrhea.

Gonorrhea is on the rise in the US

Gonorrhea has been on the rise for years in the United States, and this study suggests a key factor in its spread could be kissing.

Between 2013 and 2017, gonorrhea cases increased approximately 67% overall, according to the Centers for Disease Control and Prevention (CDC).

Read more: You're probably not getting tested for STIs as often as you should

Some gonorrhea cases have proven drug-resistant, meaning typical antibiotic treatments are now ineffective at eliminating the disease. Only one antibiotic in the United States still works in the treatment of gonorrhea (ceftriaxone).

For heterosexual people, the most common way to contract gonorrhea is genitally. The infection affects the urethra for men and the cervix for women. For gay and bisexual men, the throat, urethra, and rectum are the most common areas where gonorrhea forms.

According to the CDC, gonorrhea is prevalent among men who have sex with other men because they are less likely to share their health statuses with each other before engaging in acts that could lead to the spread of STIs.

Protecting yourself against throat gonorrhea can be difficult since people often mistake symptoms for another illness

Since most gonorrhea symptoms are similar to those of the common cold and flu, many people who have the STI don't realize it. Other times, people with gonorrhea have no symptoms. The only way to know if you have the STI for sure is to have a doctor test you.

The study's authors suggested a few ways to prevent the risk contracting throat gonorrhea, although neither of them are a sure thing. One preventative measure involves gargling antibacterial mouthwash for one minute after kissing or oral sex to kill gonorrhea bacteria. The other method involves abstaining from anal sex, where gonorrhea bacteria could be transferred from the anus to the mouth or genitals.

Although the study offered some eye-opening findings, it's difficult to generalize the results since researchers only looked at gay and bisexual men in Melbourne. Still, they raise real concerns about the ways STIs are spread in an age when they are increasingly difficult to treat.