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InfectiousICD-10: A64Approximately 20 million new STI cases occur each year in the US

Sexually Transmitted Infections

Also known as: STIs, STDs, Sexually transmitted diseases, Venereal diseases

Sexually transmitted infections are infections spread primarily through sexual contact including vaginal, anal, and oral sex. Common STIs include chlamydia, gonorrhea, syphilis, HIV, herpes, and HPV. Many STIs are curable with antibiotics, while others can be managed with antiviral medications, and prevention through safe sex practices is essential.

Symptoms

Unusual genital discharge
Painful or burning urination
Genital sores, blisters, or warts
Itching or irritation in the genital area
Pain during sexual intercourse
Rash on the body, palms, or soles
Swollen lymph nodes in the groin
Many STIs may have no symptoms at all

Causes

  • Bacterial infections such as chlamydia, gonorrhea, and syphilis
  • Viral infections such as HIV, herpes, HPV, and hepatitis B
  • Parasitic infections such as trichomoniasis and pubic lice
  • Transmission through unprotected sexual contact

Risk Factors

  • Unprotected sexual intercourse
  • Multiple sexual partners
  • History of previous STIs
  • Young age between 15 and 24 years
  • Substance use impairing judgment
  • Inconsistent condom use

Diagnosis

  • Urine tests for chlamydia and gonorrhea
  • Blood tests for HIV, syphilis, and hepatitis
  • Swab tests of genital sores or discharge
  • Pap smear and HPV testing
  • Physical examination of symptoms

Treatment

  • Antibiotics for bacterial STIs such as chlamydia, gonorrhea, and syphilis
  • Antiviral medications to manage herpes and HIV
  • Antiparasitic medications for trichomoniasis
  • HPV vaccine for prevention of HPV-related infections
  • Partner notification and treatment to prevent reinfection

Prevention

  • Consistent and correct use of condoms
  • Regular STI screening for sexually active individuals
  • HPV and hepatitis B vaccination
  • Limiting the number of sexual partners
  • Open communication with partners about sexual health

When to See a Doctor

  • Any unusual genital symptoms such as sores, discharge, or pain
  • After unprotected sex with a new or untested partner
  • If a sexual partner has been diagnosed with an STI
  • For routine STI screening as part of preventive care

Frequently Asked Questions

Related Conditions

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