Sexually transmitted infections (STIs) — sometimes called sexually transmitted diseases (STDs) — are more common than most people realize. In the United States, millions of new cases are diagnosed every year, and many more go undetected because symptoms are absent or easy to miss.
The good news: most STIs are treatable, and some are completely curable when caught early. Knowing the signs is the first step. Here’s what to watch for and when to get tested.
What Are STIs and STDs?
STIs are infections passed from one person to another through sexual contact — including vaginal, anal, and oral sex, as well as genital skin-to-skin contact. They can be caused by bacteria, viruses, or parasites.
Many people use STI and STD interchangeably. Technically, an infection becomes a ‘disease’ only when it causes noticeable symptoms — but both terms refer to the same group of conditions. Anyone who is sexually active can get an STI, regardless of age, gender, or relationship status.
Chlamydia Symptoms
Chlamydia is one of the most common bacterial STIs — and one of the trickiest, because it often causes no symptoms at all, especially in the early stages. When symptoms do appear, they typically show up 5 to 14 days after exposure.
- Burning or pain when urinating
- Unusual discharge from the penis or vagina
- Lower abdominal or pelvic pain
- Bleeding between periods or after sex
- Swollen or painful testicles
- Rectal pain, discharge, or bleeding
Note: Left untreated, chlamydia can cause fertility problems in both men and women. Testing is the only reliable way to know if you have it.
Gonorrhea Symptoms
Gonorrhea is another bacterial infection of the genital tract. Symptoms in people with penises tend to appear within 5 days of exposure; in people with vaginas, they may take up to 10 days — or may not appear at all.
- Thick, cloudy, or bloody discharge from the penis or vagina
- Burning sensation when urinating
- Heavy or irregular vaginal bleeding
- Painful or swollen testicles
- Pelvic or lower abdominal pain
- Rectal discharge, soreness, or bleeding
- Anal itching
Note: Gonorrhea can also spread to the throat, eyes, and joints. Symptoms in those areas may include eye discharge, sore throat, or joint swelling and pain.
Trichomoniasis Symptoms
Trichomoniasis is caused by a microscopic parasite. It commonly infects the vagina, vulva, or urethra. Symptoms may appear 5 to 28 days after exposure — or not at all.
- Vaginal discharge that is clear, white, yellow, or greenish
- Strong or unpleasant vaginal odor
- Vaginal itching, burning, or soreness
- Discharge from the penis
- Irritation or itching inside the penis
- Pain during sex or urination
HIV Symptoms
HIV attacks the immune system, making it harder to fight off infections. Without treatment, it can progress to AIDS. Symptoms vary by stage.
Early stage (2–4 weeks after infection):
- Fever and chills
- Fatigue and muscle aches
- Sore throat and swollen lymph nodes
- Rash
- Night sweats
- Mouth ulcers
Note: After early symptoms, HIV may enter a chronic stage with few or no noticeable symptoms — sometimes for years. The virus is still active and transmittable. The only way to know if you have HIV is to get tested.
Genital Herpes Symptoms
Genital herpes is caused by the herpes simplex virus (HSV). Most carriers never know they have it — symptoms are often absent or too mild to notice. When symptoms appear, they typically show up within 12 days of exposure.
- Small red bumps, blisters, or open sores around the genitals, rectum, or mouth
- Itching or pain in the genital area or inner thighs
- Painful urination if sores are near the urethra
- Vaginal discharge
- Flu-like symptoms during the first outbreak
Note: Herpes can be transmitted even when sores are not visible. Outbreaks can recur over time but often become less frequent.
HPV and Genital Warts Symptoms
HPV is the most common STI in the U.S. Most people have no symptoms and the infection clears on its own. However, certain strains cause genital warts, and others raise the risk of several cancers.
- Small, flesh-colored bumps or clusters in the genital area
- Warts that may be flat, raised, or cauliflower-shaped
- Itching or mild discomfort in the genital area
- Bleeding during sex
Note: The HPV vaccine is highly effective and recommended for preteens, teens, and young adults.
Hepatitis Symptoms (B & C)
Hepatitis B and C can be transmitted sexually and both affect the liver. Some people never develop symptoms. When they do, they may appear weeks after exposure:
- Fatigue and loss of appetite
- Nausea or vomiting
- Pain in the upper right abdomen
- Fever
- Dark urine or pale stools
- Yellowing of the skin or eyes (jaundice)
- Joint or muscle pain
Syphilis Symptoms
Syphilis is a bacterial infection that progresses through stages if untreated. It can eventually affect the heart, brain, and nervous system.
Primary Stage: A small, painless sore (chancre) appears where bacteria entered the body — usually the genitals, rectum, tongue, or lips.
Secondary Stage symptoms can include:
- Rough, reddish-brown rash — often on the palms or soles
- Fever, fatigue, and swollen lymph nodes
- Sore throat and muscle aches
- Patchy hair loss
- Weight loss
Note: Late-stage syphilis can cause nerve damage, vision or hearing loss, paralysis, and dementia. Pregnant people with syphilis can pass the infection to their baby. Treatment is critical at every stage.
When Should You Get Tested?
You should consider STI testing if:
- You have a new sexual partner
- You or your partner has had unprotected sex
- You notice unusual symptoms — discharge, sores, rashes, or pain
- You’re pregnant or planning to become pregnant (our women’s health services can help)
- It’s been more than a year since your last STI screening
Note: Many STIs have no symptoms. Routine testing is the only way to know your status — and to protect your health and your partners’.
How to Lower Your Risk
Practical steps that significantly reduce the risk of contracting or spreading an STI:
- Use condoms consistently during every sexual encounter
- Get vaccinated — vaccines exist for HPV and hepatitis B
- Talk openly with new partners about STI testing before sexual activity
- Limit the number of sexual partners
- Ask your provider about PrEP if you’re at higher risk for HIV
- Get tested regularly, especially if you have multiple partners
Think you may have been exposed to an STI? Oak Lawn Immediate Care offers confidential STD testing and treatment — no appointment needed. Walk in today, or schedule an appointment in advance if you prefer.