Oral sex describes when the tongue or mouth is used to lick or suck on another person's genitals, anus and surrounding areas. Many people think oral sex is a safe form of sex - however, this is a myth and you can get sexually transmitted diseases in the mouth. Read more about the different STDs you can get in the mouth here
Can all STDs be transmitted by mouth?
Both the mouth and throat are mucous membranes, and it is through contact between mucous membranes that STDs can be transmitted. Many STDs can be transmitted from the anus and genitals to the mouth and throat. Conversely, not all STDs can be transmitted from the mouth and throat to the anus and genitals.
First, it is important to state: When talking about STDs, we can distinguish between those caused by bacteria and those caused by viruses. A bacterium will be local, so you can be infected in one place - for example, your mouth - without being infected in another place - for example, your anus. That's why you can infect yourself (and others) if you don't wash your hands after having sex or masturbating, and then touch yourself somewhere else on your body where there is a mucous membrane.
STDs caused by viruses will however spread all throughout your body and all your mucous membranes.
The STD most often contracted through oral sex is herpes. You may not have thought that a cold sore on the corner of your mouth or lip is actually a herpes outbreak - but it is. Herpes is very contagious and, as well as being on the face, it can also spread to the genitals and anus. Both condoms and dental dams have little effect in preventing infection with the herpes virus - the recommendation is therefore not to have sex or kiss if you have an outbreak and until the sores have cleared. You can read more about herpes in our guide right here.
Chlamydia can be transmitted from the genitals and anus to the mouth and throat through oral sex. The bacteria can cause symptoms such as burning, soreness and throat inflammation. The chlamydia bacterium stays in the throat until you are treated, so it cannot travel through the body.
It is not yet known whether chlamydia can spread from the mouth to the genitals and anus. You can protect yourself against chlamydia in the throat by having oral sex with dental dams or condoms. You can read more about chlamydia and how it is treated here.
Gonorrhoea is a sexually transmitted bacterium and can be transmitted to the throat, where it can reside on and in the tonsils. If you are infected with gonorrhoea through oral sex, you may get symptoms such as pain or itching in your throat.
Gonorrhoea can be transmitted by oral sex from both the genitals and anus to the throat - similarly it can be transmitted from the throat to the genitals and anus. You can protect yourself from gonorrhoea in the throat by having oral sex with dental dams or condoms. You can read more about gonorrhoea in our article here.
HPV is a virus that is transmitted through sexual contact. HPV can be transmitted from the genitals and anus to the mouth and throat - similarly, it can be transmitted from the mouth and throat to the genitals and anus. There are about forty different types of HPV that can be transmitted by mucosal contact - in the case of infection in the mouth and throat, the virus will often be located at the root of the tongue and in the tonsils.
Some types of HPV can cause genital warts, while others - in rare cases - can cause cancer. If you are infected with HPV through oral sex, you may therefore be at risk of developing genital warts or cell changes in your mouth or throat. You can protect yourself from HPV through oral sex by using dental dams or condoms - however, just like with herpes, the virus may be present on the skin outside the areas covered by the dental dams or condom. You can also choose to be vaccinated against HPV infection. You can read our guide to genital warts here.
You can also read more about how to use a dental dam here.
Syphilis is a sexually transmitted disease caused by a bacterium - but the disease is not very common in Denmark. Syphilis is transmitted through all forms of sexual contact, including other close mucosal contact such as kissing. Syphilis appears in three stages: the first stage appears as a small sore that disappears again in a few weeks. The second stage starts two to three months after infection, and appears as flu-like symptoms and a rash all over the body. The third stage can be life-threatening and includes blindness, paralysis and inflammation of the nervous system or brain. The third stage typically occurs five to twenty years after initial infection with syphilis. You can protect yourself from syphilis by using a dental dam or condom during oral sex.
If you have HIV and are not on treatment, the virus will be present in semen, pre semen, vaginal secretions and blood. You can therefore contract HIV from oral sex, especially if you have semen or (menstrual) blood in your mouth. It is not as easily transmitted if you put semen or vaginal secretions in your mouth.
HIV is not usually transmitted by kissing or receiving oral sex, but it can be transmitted if you have a scratch in your mouth or throat and therefore get blood in your mouth. You can protect yourself from HIV by using a dental dam or condom during oral sex. For more information on HIV, read our article here.
Hepatitis A and B
Both hepatitis A and hepatitis B are viruses that can cause inflammation of the liver and/ or liver failure. Hepatitis A is highly contagious and is transmitted through faeces - this means that you can transmit hepatitis A through oral sex, by giving a rim job, where there is mucosal contact with the rectum.
Symptoms of hepatitis A begin about three weeks after infection, and include fever, muscle aches, fatigue, headache, nausea and stomach ache. You may also notice that your urine changes colour for a while and that your skin and eyes turn yellow. Most people recover after a few weeks, after which they are immune - in some cases however they can develop liver failure and die from the disease. Hepatitis A is not very common in Denmark, and most people are infected when travelling. You can protect yourself against hepatitis A by getting vaccinated - just as you can protect yourself against getting the virus through your mouth by using dental dams or condoms when having oral sex in the anus.Hepatitis B is the most common form of hepatitis and is transmitted through semen, pre semen, vaginal secretions and blood. It typically takes a few months from being infected for symptoms to appear - most people experience only mild symptoms or no symptoms at all. Symptoms include fever, fatigue, headache, nausea and muscle aches. As with hepatitis A, you may find that your urine changes colour for a while and your skin and eyes become yellowish - if you are infected with hepatitis B, your poop may also become whitish. Most infected people recover within a few months - but up to ten percent develop chronic hepatitis with an increased risk of cirrhosis and liver cancer. You can protect yourself from hepatitis B infection from oral sex by using dental dams or condoms. You can also be vaccinated against hepatitis B.
You can also read our guide to haemorrhoids here, or 10 myths about sex here!