Sexually Transmitted Infections

If you are sexually active, there are many STIs that you should know about. It is also good to be tested regularly and get treatment, if needed, to minimise the risk of transmission to someone else.


Gonorrhea is a bacteria that is transmitted through the mucous membranes or through bodily fluids that come in contact with mucous membranes. About 2,500 cases of gonorrhea are diagnosed in Sweden every year (2017). More than half of the reported cases regard transmissions between men who have sex with men. Recently the number of cases of gonorrhea has increased dramatically in Sweden. Between 2016 and 2017 there was a 42 % increase in the number of cases. 

Gonorrhea is easily transmitted through anal and vaginal intercourse and can affect the genitals, anus, eyes or throat. Wearing a condom is the easiest way of reducing the risk of transmitting gonorrhea, or having sex without intercourse.

Gonorrhea can be transmitted through oral sex, so a condom can be used to reduce the risk as both the giver and receiver can potentially contract gonorrhea.

Some people with gonorrhea are asymptomatic, however, symptoms usually appear within 2-10 days and include painful urination. Anal infections can lead to pain and anal bleeding. Gonorrhea of the throat is usually asymptomatic.


A cotton swab test is taken from the throat, cervix, anus, and inside the eyelid. Gonorrhea of the urinary tract can be tested through a urine sample, but must be followed up with a cotton swab test, if it is positive.


Gonorrhea is treated with a one time dose of antibiotics administered by injection, or as oral antibiotics. Treatment resistant types of gonorrhea are an increasing problem, so treatment is always followed up.

Good to Know

Gonorrhea increases the risk of contracting HIV and other STIs. It can also damage the Fallopian tubes and the epididymis which can impact the ability to conceive children.

Gonorrhea is a rare sexually transmitted infection, but it is more common in men who have sex with men, especially men who live with HIV. It is included in the Communicable Diseases Act, which means that if you have gonorrhea, you must trace who might have transmitted it to you and to whom you might have transmitted it.


Chlamydia is one of the most common sexually transmitted infections in Sweden. It can be hard to detect since it is often asymptomatic. About 34,000 people test positively for Chlamydia every year in Sweden. (2017)

Chlamydia is transmitted through the mucous membranes or through bodily fluids, most easily through anal or vaginal intercourse, and affecting the genitals, anus, and the throat.

The symptoms of chlamydia vary depending on where the infection is – it can cause discharge from the genitals and painful urination. Discharge can also come from the anus. Chlamydia of the throat presents the same symptoms as a bacterial throat infection.

Chlamydia can be transmitted through oral sex, so to reduce that risk a condom can be used.

There is a small chance that chlamydia can be transmitted through hands or sex toys and you can reduce that risk by washing your hands and changing condoms on sex toys. A rule is to always get tested for chlamydia if you are sexually active.


Chlamydia is tested through a urine sample that is combined with a cotton swab of the wall of the vagina. Swabs of the throat and anus are also made, depending on where the infection is.

Tests for chlamydia can be bought online or at the pharmacy and done at home. If you have a penis, you have to send a urine sample to a laboratory and, if you test positively, you have to seek treatment. Note that these at-home tests only apply to genital chlamydia. Men who have sex with men are more likely to contract chlamydia of the throat or anus.

Chlamydia has an incubation period of one week, so you will have to wait seven days after sex to get tested.


Chlamydia is treated by antibiotics, usually for nine days.

Good to Know

Chlamydia increases the risk of contracting HIV and other sexually transmitted infections. It can also damage the Fallopian tubes and the epididymis which can impact the ability to conceive children.

Chlamydia is included in the Communicable Diseases Act, which means that if you have chlamydia, you must trace who might have transmitted it to you and to whom you might have transmitted it.

There is a form of chlamydia, LGV (Lymfogranuloma venereum) that is rare but has become more common in recent years, especially among men who have sex with men and live with HIV. It is transmitted in the same way as typical chlamydia, but can result in sores on the genitals, throat, or anus, with swollen lymph nodes, bleeding and other stomach symptoms. It can also be asymptomatic and still be transmittable. LGV treatment requires double the antibiotic dose than typical chlamydia.

Mycoplasma genitalium is a rare sexually transmitted infection that resembles chlamydia, with the same symptoms and transmitted in the same way. If you have symptoms of chlamydia and your test is negative, you can get tested for mycoplasma. Mycoplasma is treated with antibiotics.


Syphilis is a bacterial infection that was almost eradicated in Sweden, but in recent years there has been an increase in infections. About 400 people are diagnosed with syphilis every year, and 85% of those are men who have sex with men.

Syphilis is transmitted via mucous membranes, but can also be transmitted via the skin in areas where there are sores caused by the infection. Syphilis is easily transmitted through unprotected intercourse and those who have recently contracted the infection are more likely to transmit it than someone who has had it for a long time. Syphilis is a systemic disease, throughout the whole body.

Condoms are a good way to reduce the risk of transmission, but other kinds of close contact can also be a risk. It is important to get tested for syphilis regularly if you have sex with multiple partners.

Syphilis is a serious illness with different stages of development. The first stage lasts between 3 weeks and 3 months, a sore can appear at the site where the syphilis entered the body, and the lymph nodes in the area are often swollen.

The second stage begins at 7 to 10 weeks, where you are likely to get a fever, swollen lymph nodes and a rash. However, some people do not notice their symptoms.


Syphilis is diagnosed through a blood test, but a cotton swab of the sore can also be done.


Syphilis is treated with antibiotics. Penicillin is often administered twice by injection, with one week in between.

Good to Know

Syphilis is rare, but a serious illness and, if left untreated, can cause damage to nerves and organs.


Hepatitis is a group of viruses. The skin and eyes may turn yellow, but not always, and you may experience fever, fatigue and nausea. Hepatitis A, B, and C are the most common forms of the virus.

Hepatitis A

Hepatitis A is transmitted via faeces and in some cases via rimming. There is an ongoing outbreak of hepatitis A among men who have sex with men in Europe. If you are a man who have sex with other men, vaccination for hepatits A is recommended. After two shots of vaccine, with six months between each shot, you have a 30 year long protection against hepatitis A.

Hepatitis B

Hepatitis B is transmitted via blood and sex in the same way as HIV and causes liver inflammation. The virus is present throughout the body, in blood, sperm and lubrication. Condoms are a good way to reduce the risk of transmission via vaginal or anal intercourse, and when having oral sex. You can also get vaccinated against Hepatitis B.

Hepatitis B has an incubation period of 2 to 3 months. Only half of those who contract Hepatitis B get any symptoms, they can include nausea, diarrhoea, vomiting and stomach ache, and pains in joints and muscles. The urine can darken, the faeces become lighter and the whites of the eyes can yellow. The infection often heals on its own.

Hepatitis B vaccination is free for men who have sex with men. All children born in Sweden are vaccinated against Hepatitis B.

Hepatitis C

Hepatitis C is transmitted via the blood. It can be sexually transmitted, but the risk is low.

Hepatitis C has an incubation period of 2 to 3 months with only a quarter of those infected developing symptoms. The symptoms are yellowing of the skin, nausea and stomach pains. Hepatitis C can lead to cirrhosis of the liver and liver cancer.

Medicines used today cure almost all cases of Hepatitis C, but they are expensive and not available to everyone.


Hepatitis is diagnosed through a blood test taken after the incubation period.

HPV and Condyloma

HPV (human papillomavirus) exists in many forms and is very common. The majority of people with an active sex life will at some time contract HPV. Some forms of the virus cause genital warts called condyloma.

HPV can be transmitted between mouth and genitals, genitals to genitals, or skin to skin contact. Condoms are a good way to reduce the risk of transmission.

On the penis, warts are most often found on the foreskin, the glans or penis shaft. With the vagina, warts are often on the labia, around the urinary tract and inside the vagina. They can also be on the cervix, where they are hard to find. HPV can infect cells in the throat or the mouth as well. The warts can hurt, but a lot of the times they don’t.

Some HPV-strains can cause cancer of the cells they infect.

Testing and Treatment

HPV is diagnosed through the presence of warts. Everyone with a female personal identity number (personnummer) who is between 23 and 60 years of age are regularly called for a pap smear. Cells from the cervix are analysed to identify any cellular changes that might lead to cancer.

The warts usually disappear after a few months and need no treatment. If they are bothersome, they can be treated with creams or removed surgically.

Good to Know

There is a vaccine against two types of condyloma that can cause cell changes. The vaccine is free for adolescents with a female person number and is most effective if taken before becoming sexually active.

HPV can be transmitted from vagina to vagina, which is why it is important to get regular pap smears. If you have a vagina and a male person number, you will not be called for testing and need to make an appointment yourself.

RFSL wants all young people, regardless of gender, to be able to access the vaccine for free.


Herpes is a virus that infects the nerves of the body with the lips and genitals being most commonly affected. Herpes is not a serious illness, but the blisters can hurt and be uncomfortable and usually flare up in episodes. Between episodes, the virus lies dormant in the nerves of the mucous membranes.

Herpes is transmitted through contact between mucous membranes, and the mucous membrane and skin, via saliva and other bodily fluids. The blisters most often appear on the genitals, anus and/or mouth.

There are two types of herpes – type 1 and type 2. Type 1 used to be called oral herpes, but can affect both the genitals and the mouth. Type 2 was called genital herpes and rarely affects the mouth. To reduce the risk of transmission, it is best to avoid touching the infected mucous membrane with another mucous membrane, so avoid giving oral sex if you have blisters on your lips, and use condoms when having intercourse.


Herpes is diagnosed by looking for blisters, as well as with a blood test. The incubation period for herpes is between 2 and 20 days.


Herpes is treated with a virus suppressing ointment or tablets.

Good to Know

An estimated 50-90% of all adults are carriers of herpes type 1, and between 15-30% of herpes type 2.

Having blisters increases the risk of contracting HIV and other sexually transmitted infections. Herpes is a life long infection.

Bacterial Vaginosis

Bacterial vaginosis produces a foul smelling discharge from the vagina as a result of changes in the bacterial composition and may itch and sting a bit. Bacterial vaginosis is very common, and most people with a vagina will get it at some point in their lives. Bacterial vaginosis is not usually included as an STI since it does not typically transmit from one person to another. Bacterial vaginosis is treated with antibiotics.

Yeast Infection

A yeast infection means that the natural fungus present in the vagina has increased which causes itching and irritation. A yeast infection is harmless and is not a sexually transmitted infection. There is both prescription and non-prescription medication available. Individuals with a penis rarely get a yeast infection.

Urinary Tract Infection

Urinary tract infections are common among people who have a vagina, and are treated with antibiotics. The most common symptom is painful urination. A urinary tract infection is not an STI, but the friction that sex causes can facilitate bacterial growth.