Sexually Transmitted Infections (STIs)

Common STIs

• Chlamydia — most common bacterial STI; often asymptomatic; can cause infertility if untreated
• Gonorrhea — bacterial; often asymptomatic in women; antibiotic resistance is rising
• Syphilis — bacterial with multiple stages; can be congenital; resurging in many populations
• HIV — chronic viral; controllable with daily medication
• HPV / genital warts — most common viral STI; some types cause cancer
• Herpes (HSV) — lifelong; suppressive treatment available
• Trichomoniasis — parasitic; curable with antibiotics
• Hepatitis B and C — viral; B has a vaccine; C is now usually curable

Possible Symptoms

Many STIs cause no symptoms. When present, signs may include:

• Unusual discharge from the genitals
• Pain or burning with urination
• Genital sores, warts, or rashes
• Pelvic or testicular pain
• Painful intercourse
• Itching or irritation
• Flu-like symptoms in early HIV or syphilis

Testing

Recommended testing depends on age, sex, and risk factors. Common scenarios:

• Routine HIV testing for all adults at least once
• Annual chlamydia and gonorrhea testing for sexually active women under 25
• Testing for new or multiple partners
• HCV screening at least once for adults
• Prenatal STI screening in pregnancy

Prevention

• Vaccinate — HPV vaccine, hepatitis B vaccine
• Use condoms consistently and correctly
• Limit number of sexual partners and discuss STI testing
• Consider PrEP (pre-exposure prophylaxis) for HIV prevention if at risk
• Treat partners when you are diagnosed
• Avoid sharing needles

When to See a Doctor

See a doctor for any concerning symptoms after sexual contact, after potential exposure, before starting a new sexual relationship, in pregnancy, or per routine screening intervals.

Related Conditions

References

• Centers for Disease Control and Prevention. STI Treatment Guidelines.