STI Guide

The term STIs stands for sexually transmitted infections, meaning those that can be transmitted primarily (but not exclusively!) through sexual contact. These include, for example, chlamydia, gonorrhea, syphilis, and HIV. Many STIs initially show no symptoms, but if left untreated, they can have health consequences.

The term STDs stands for sexually transmitted diseases. The term is often used synonymously with STIs, but it describes the disease that can arise from an infection. While an infection can exist without symptoms, a "disease" is referred to when symptoms appear.

Today, the term STI is increasingly used because it is more precise: not every infection automatically leads to illness. In German, the term "Geschlechtskrankheit" (venereal disease) is still common, but it is inaccurate and can be stigmatizing. With STI, we emphasize the medically correct and more neutral expression.

Chlamydia are bacteria (Chlamydia trachomatis) and are among the most common sexually transmitted infections. They often present without symptoms, but if left untreated, they can lead to serious long-term consequences, such as infertility.

• Young people between 15 and 25 years old.
• Gay and bisexual men of all ages.
• The special form LGV (lymphogranuloma venereum) occurs in Germany almost exclusively in men who have sex with men.

• Vaginal, anal or oral through mucous membrane contact.
• Smear infections during sex are also possible.

• Condoms significantly reduce the risk.
• Early detection: For women up to 25, statutory health insurance covers the cost of one chlamydia test per year. It's best to ask your health insurance provider if you are eligible.

Often none, which is why many infections go unnoticed. If symptoms do occur, they may include, for example:

• Women: Discharge (watery or purulent), itching, burning during urination.
• Men: Clear discharge from the urethra, burning during urination.
• Rectal: Discharge, itching, sometimes pain.
• Throat: Usually no symptoms.
• LGV: Severe pain, swollen lymph nodes in the groin, bleeding, difficulty with bowel movements.

• Urine sample.
• Swabs from urethra, cervix, rectum, or throat.
• For LGV: Special examination to differentiate from other forms of chlamydia.

• Typically antibiotics for at least one week (three weeks for LGV).
• Sexual partners from recent weeks are usually treated as well, even without a separate test, to avoid ping-pong infections.

• Chlamydia is highly treatable.
• If detected early, long-term complications can be avoided.
• Regular tests are particularly important if you have multiple partners.

Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. If left untreated, it can affect various organs and cause severe long-term complications, but it is highly curable with antibiotics.

• In Germany, there are approximately 7,000–8,000 new cases annually.
• Most frequently affected: men who have sex with men (MSM).
• More common in large cities.
• Mandatory reporting: Cases are reported anonymously to the health authorities.

• Mainly through close mucous membrane contact during vaginal, anal, or oral sex.
• Infection occurs through small wounds or direct contact with ulcers or moist warts (condylomata lata).
• Less commonly: From mother to child during pregnancy, through blood, or via needlestick injuries.

• Condoms significantly reduce the risk (approx. 95%), but do not offer complete protection, as sores can also be located outside the condom-covered area.
• Regular testing for at-risk contacts – especially recommended for MSM with changing partners (every 3–6 months).
• Pregnant women are routinely tested in Germany.

Syphilis progresses in several stages:

• Early stage (after approx. 3 weeks): Painless ulcer at the entry site (genitals, anal area, mouth) + swollen lymph nodes.
• Second stage: Rash (often on palms and soles of feet), flu-like symptoms, moist warts in skin folds, hair loss.
• Latency: Often asymptomatic for years, but still detectable.
• Late stage (rare): Severe damage to the brain, heart, nerves, and other organs.

• Blood test (antibody detection).
• In early stages, direct pathogen detection from the wound is also possible.
• In case of suspected involvement of the nervous system: examination of the cerebrospinal fluid.

• Standard treatment: Penicillin injection (single dose or over several weeks, depending on the stage).
• Alternative for penicillin allergy: Other antibiotics (e.g., doxycycline).
• Important: Sexual partners from the last few weeks or months should also be treated to prevent re-infection.

• Syphilis does not lead to immunity; one can become reinfected at any time.
• Early detection protects against severe late complications.
• Testing is particularly important with new or changing partners.

Gonorrhea, also colloquially known as the clap, is a sexually transmitted infection caused by bacteria (Neisseria gonorrhoeae). It can affect the genitals, rectum, and throat, often without any noticeable symptoms.

• Approximately 25,000-30,000 new cases per year in Germany.
• Second most common bacterial STI after chlamydia.
• Particularly affected: Men who have sex with men (MSM) and young adults with multiple partners.

• Vaginal, anal, and oral sex.
• Transmission also possible through finger or sex toy contact if condoms or protective barriers are not used.
• Mother-to-child transmission possible during birth.
• No infection through toilets, towels, or swimming pools.

• Condoms and dental dams significantly reduce the risk.
• Regular testing for those with frequently changing partners; recommended every 3–6 months for MSM.
• Tests can screen for Chlamydia and Gonorrhea simultaneously.

Often none, especially in the throat or rectum. If there are symptoms, they may include:

• Women: Increased discharge, intermenstrual bleeding, lower abdominal pain.
• Men: Yellow-purulent discharge from the urethra, burning during urination.
• Rectal: Itching, discharge, sometimes bleeding.
• Throat: Usually asymptomatic, sometimes sore throat.
• If left untreated, gonorrhea can lead to inflammation, infertility, and chronic pain.

• Urine sample.
• Swabs from the urethra, cervix, throat, or rectum.
• Modern tests (PCR) are very reliable and also detect asymptomatic infections.

• Standard: Single dose antibiotic injection (ceftriaxone).
• In case of suspected resistance: Antibiotics after testing.
• Important: Sexual partners of the last 60 days should also be treated, even without their own test, to prevent re-infection.

• No lasting immunity; reinfection possible at any time.
• Resistant gonorrhea strains (super gonorrhea) are increasing worldwide; timely and correct treatment is important.
• Cure verification is recommended, especially for pharyngeal infections or during pregnancy.

HIV (Human Immunodeficiency Virus) attacks the immune system. If left untreated, it can lead to AIDS. Thanks to modern medications, people with HIV who receive timely treatment can now live almost as long as people without HIV.

• Globally, approximately 40.8 million people live with HIV.
• In Germany, approximately 96,700 people live with HIV, about 8% of whom are unaware of their infection.
• The number of new infections in Germany has remained stable for years.

• Sexual: Primarily through unprotected anal or vaginal intercourse (highest risk with passive anal sex).
• Blood contact: Sharing needles or syringes, blood transfusions (extremely rare in Germany).
• Mother-to-child transmission: During pregnancy, birth, or breastfeeding is almost entirely prevented in Germany thanks to treatment.
• Not contagious through: Shaking hands, hugging, kissing, sharing dishes.

• Condoms: Significantly reduce the risk.
• PrEP (Pre-Exposure Prophylaxis): Preventive medication; when taken correctly, can be almost 100% effective.
• PEP (Post-Exposure Prophylaxis): Emergency medication that must be started within 72 hours of potential exposure.
• Regular testing: If detected early, HIV is highly treatable.

• Often no noticeable symptoms initially.
• In the first few weeks after infection: flu-like symptoms such as fever, night sweats, sore throat and body aches.
• Skin rash, swollen lymph nodes, fatigue.
• Nausea, diarrhea, or weight loss.
• In later stages (without treatment): increasing immunodeficiency, frequent infections, opportunistic diseases.

• Blood sample (venous blood).
• Blood from the finger (capillary blood).
• Oral mucosa swab / saliva.
• Plasma / serum for highly sensitive laboratory tests.

• Antiretroviral Therapy (ART): Daily pills or long-term injections keep the viral load so low that HIV is no longer detectable.
• "U = U": If HIV remains below the detection limit, it is not transmitted during sex.
• Treatment should begin immediately after diagnosis.

• With good treatment, people with HIV can now lead an almost normal life.
• Modern therapies are very well tolerated and often available as a single tablet.
• The earlier the diagnosis, the better the prognosis.

Hepatitis C is a viral infection that primarily affects the liver. If left untreated, it can lead to liver inflammation, cirrhosis, and liver cancer. However, with modern medications, it is now curable in almost all cases.

• Worldwide: approx. 50 million people.
• Germany: estimated approx. 189,000 chronic infections.
• Many affected individuals are unaware of their illness, as it often causes no symptoms.

• Mainly through blood-to-blood contact, e.g. sharing needles or drug paraphernalia, unsterile tattoos or piercings, or needlestick injuries in a medical setting.
• Sexual transmission is rare. However, the risk is increased with co-occurring STIs.
• Mother-to-child transmission during birth is possible.
• No infection through handshakes, kissing, or sharing dishes.

• Do not share needles, syringes, or accessories.
• Use sterile conditions for piercings and tattoos.
• Use condoms for risky contacts.
• Maintain hygiene in medical and private areas (own razors, toothbrushes).
• Get regular tests if risk factors exist.

Often no or only non-specific symptoms such as fatigue, muscle pain or problems with concentration. Possible signs of an acute infection, on the other hand, are:

• Yellowing of the skin or eyes (jaundice).
• Dark urine, light stools.
• Upper right abdominal pain.

If left untreated, hepatitis C can lead to cirrhosis or liver cancer over many years.

• Blood test for hepatitis C antibodies.
• If positive: Viral detection in blood (HCV RNA test).
• Liver examinations to assess damage (e.g., ultrasound, elastography).

• Modern tablet-based therapies (DAAs) over 8 to 12 weeks.
• Cure rates over 95%.
• Treatment costs are covered by health insurance in Germany.
• No vaccination possible.
• Reinfection is possible after recovery.

• Early diagnosis prevents severe long-term complications.
• If there is an existing risk, get tested regularly.
• Today's treatment is short, well-tolerated, and very successful.

HPV (human papillomaviruses) are very common viruses that can affect the skin and mucous membranes. There are over 200 types; some cause harmless warts, while others can cause cancer.

• More than 80% of all sexually active people become infected at some point.
• In most cases, the infection clears up on its own within 1–2 years.
• Anyone can be affected.

• Mainly through sexual contact (vaginal, anal, oral), even without penetration.
• Less frequently during childbirth from mother to child.
• Condoms reduce the risk but do not offer complete protection.

• Vaccination: Provides very reliable protection against the most common dangerous HPV types.
• Recommended for all children and adolescents between 9 and 14 years of age (catch-up vaccination up to 17 years).
• Cost coverage: Many health insurance companies fully cover the HPV vaccination up to a certain age. Be sure to ask your health insurance company up to what age they cover it.
• Condoms: Reduce risk and also protect against other STIs.
• Early detection: Regular check-ups, e.g., Pap test at the gynecologist.

• Low-risk types: Genital warts (unpleasant, but not dangerous).
• High-risk types: Changes in cells that can lead to cancer, e.g., cervical, anal, or throat cancer.

• Cervical smear (Pap test) for early detection of cell changes.
• HPV DNA test for direct detection of the virus, often combined with the Pap test.
• Visible warts in the genital or anal area can be diagnosed clinically.
• There are no routine screenings for men; tests are usually symptom-oriented.

• In many cases, an HPV infection clears up on its own, without treatment.
• Visible changes such as genital warts can be removed with creams, cryotherapy, laser, or surgery.
• Cell changes on the cervix are observed and removed depending on the findings.
• There is currently no causal treatment against the virus itself.

• Most HPV infections disappear on their own.
• Only a few become chronic and can cause cancer. Regular check-ups are therefore important.
• HPV can affect anyone, regardless of gender.

Herpes is an infection caused by herpes simplex viruses, typically presenting as painful blisters on the lips, genitals, or other parts of the body. The viruses remain in the body permanently and can reactivate during periods of weakened immune system or stress. The two types are called HSV-1 and HSV-2.

• Almost all people are affected by HSV-1; the infection usually manifests itself on the lip, but can also spread from there to the genitals or anal mucous membrane of the partner.
• About 20% of the population is affected by HSV-2; the infection usually manifests itself painfully in the genital area. Heterosexual people are more frequently affected. Once infected, symptomatic phases are possible at any time. The frequency varies greatly individually.

• Genital, rectal, oral: Mucosa-to-mucosa contact.
• Smear infection: Contact with infectious fluid from the vesicles.

• Condoms only minimally reduce the probability of transmission. HSV is also transmitted "around the condom": during kissing, during oral sex, by touch (via the fingers).
• Avoid contact with blisters or sores.
• If blisters form on the genitals or lips, refrain from (oral) sex and kissing until they heal, which is usually after 1–2 weeks.

• Genital, rectal, oral: burning, painful, itchy blisters.
• The lesions (the blisters) always heal, with or without treatment. However, the herpes viruses remain "hidden" in nerves and can therefore reappear in the same place, especially under stress, strong sun exposure (lips), or other simultaneous infectious diseases.
• In immunocompromised individuals, severe courses with organ involvement and brain involvement are possible.

• Medical examination based on typical blisters and symptoms.
• Swab of the blister fluid for direct virus detection in the lab.
• Blood test for antibodies if the infection is unclear or without visible symptoms.

• For mild cases: local treatment with ointment.
• For severe cases: antivirals (medications that inhibit virus replication) as tablets or intravenously.

• Herpes viruses remain in the body for life after an infection.
• Herpes is not curable, but outbreaks can be treated and well controlled.
• Stress, sun, or a weakened immune system can trigger an outbreak.
• The blisters are contagious, especially with direct skin or mucous membrane contact.