STIs Overview: Managing Chlamydia, Gonorrhea, and Syphilis Today

Three bacterial STIs - chlamydia, gonorrhea, and syphilis - are surging again, even as we have the tools to stop them. In 2021, the U.S. reported over 2.5 million cases of just these three infections. Half of them were in people under 25. Many of these cases never show symptoms, which means they spread silently. Left untreated, they can cause infertility, chronic pain, and even brain damage. But here’s the good news: we know exactly how to test for them, treat them, and stop them from spreading. The problem isn’t lack of knowledge. It’s lack of action.

What You Need to Know About Chlamydia

Chlamydia is the most common bacterial STI in the world. It’s caused by Chlamydia trachomatis a bacterium that infects the cervix, urethra, rectum, and throat. Up to 95% of infected women and half of infected men feel nothing at all. That’s why it’s called a silent infection. When symptoms do show up, they’re often mistaken for a urinary tract infection: burning during urination, unusual discharge, or spotting between periods. In men, it might cause testicle pain.

Left alone, chlamydia can lead to pelvic inflammatory disease (PID) in about 10-15% of women. PID scars the fallopian tubes, which can result in ectopic pregnancy or permanent infertility. The risk doesn’t go away after treatment - about 1 in 5 young women get reinfected within a year if their partners aren’t treated too.

Testing is simple. A urine sample or a swab from the vagina, rectum, or throat can detect it. The CDC recommends annual screening for all sexually active women under 25 and for anyone with new or multiple partners. Men who have sex with men should also get tested at least once a year, or every 3-6 months if they’re having condomless sex.

Treatment? One pill - azithromycin - or a week of doxycycline pills. Both work in over 95% of cases. But here’s the catch: you must avoid sex for seven days after starting treatment. And your partners? They need treatment too, even if they feel fine. If you don’t, you’ll just pass it back and forth.

Gonorrhea: The Antibiotic-Resistant Threat

Gonorrhea, caused by Neisseria gonorrhoeae a highly adaptable bacterium that thrives in warm, moist areas of the body, is the second most common bacterial STI. Like chlamydia, it often has no symptoms - especially in women. When symptoms appear, they include thick yellow or green discharge, painful urination, and bleeding between periods. In men, it can cause swelling in the testicles or a pus-like discharge.

The real danger? Antibiotic resistance. Gonorrhea has outsmarted nearly every drug we’ve thrown at it. In the 1980s, penicillin worked. Then tetracycline. Then ciprofloxacin. Now, only one class of antibiotics reliably kills it: cephalosporins. The CDC’s current standard is a single shot of ceftriaxone (500 mg) plus one pill of azithromycin. This dual approach slows resistance.

But even that’s not foolproof. In some areas, up to half of gonorrhea strains show reduced sensitivity to azithromycin. That’s why test-of-cure is required for throat infections - they’re harder to treat. If you have symptoms after treatment, go back. Don’t assume it’s gone.

What’s new? A drug called zoliflodacin a novel oral antibiotic targeting bacterial DNA replication just finished Phase 3 trials with 96% success. It could be approved by 2025 and might become the first new gonorrhea treatment in decades. Until then, prevention is everything. Condoms reduce transmission by 60-90%. Regular testing - every 3-6 months if you’re at higher risk - is non-negotiable.

Syphilis: The Great Imitator Is Back

Syphilis is different. It doesn’t just cause discharge or pain. It evolves. It’s caused by Treponema pallidum a spiral-shaped bacterium that spreads through direct contact with a sore and moves through stages - sometimes over years.

Stage one: a single, painless sore - called a chancre - appears where the bacteria entered, usually on the genitals, anus, or mouth. It heals on its own in 3-6 weeks. That’s why people don’t seek help. Stage two: a rash - often on the palms and soles - appears, along with fever, swollen lymph nodes, and fatigue. Again, it fades. Then comes the latent stage. No symptoms. But the bacteria are still in your body.

Years later, untreated syphilis can attack your heart, brain, nerves, and eyes. It can cause dementia, stroke, blindness, or death. That’s why it’s called the “great imitator” - it mimics so many other diseases.

Testing requires a blood test. Rapid tests are now available in clinics and even at-home kits. If caught early - within the first year - one shot of benzathine penicillin G a long-acting form of penicillin that kills Treponema pallidum (2.4 million units) cures it. Late-stage syphilis needs three weekly shots.

The worst part? Congenital syphilis. In the U.S., cases jumped 273% between 2017 and 2021. Babies born with it can die, be born with deformities, or suffer lifelong brain damage. That’s why the CDC now recommends testing all pregnant women at their first prenatal visit - and again at 28 weeks in high-risk areas.

How to Protect Yourself and Others

Condoms aren’t perfect, but they cut transmission by 50-90% depending on the STI. They’re your first line of defense. But here’s something newer: DoxyPEP a post-exposure prophylaxis using doxycycline taken within 72 hours after condomless sex. Three major studies showed it reduced chlamydia, gonorrhea, and syphilis by 47-73% in men who have sex with men and transgender women taking PrEP. But it didn’t work for cisgender women in trials. So it’s only recommended for high-risk MSM and trans women right now.

That’s why testing and treatment of partners matter so much. If you test positive, you must tell everyone you’ve had sex with in the past 60 days for chlamydia and gonorrhea - up to 90 days for syphilis. Health departments can help notify partners anonymously. You don’t have to do it alone.

Retesting is critical. Don’t wait until you feel sick. Get tested again three months after treatment. Reinfection is common, especially in young people. And if you’re on PrEP for HIV? Talk to your provider about DoxyPEP. It’s not for everyone - but if you’re having condomless sex with multiple partners, it could be a game-changer.

The Bigger Picture: Why This Matters

These infections aren’t just about sex. They’re about access. Black Americans are diagnosed with chlamydia at 5.6 times the rate of white Americans. Gonorrhea rates are 6.7 times higher. Syphilis is 3.5 times more common. Why? Lack of testing sites, stigma, distrust in healthcare, and poverty. We can’t treat our way out of this. We need better screening programs, community outreach, and affordable care.

The economic cost? Over $16 billion a year in the U.S. alone. That’s $500 million just for chlamydia treatment. Globally, the STI testing market is growing fast - expected to hit $5.1 billion by 2028. But money means nothing if people don’t get tested.

The WHO wants to cut syphilis in pregnant women by 90% and chlamydia/gonorrhea by 70% by 2030. That’s ambitious. But it’s possible - if we stop treating STIs like a moral issue and start treating them like the public health crisis they are.

You don’t need to be promiscuous to get an STI. One unprotected encounter is enough. You don’t need to feel sick to be infected. You don’t need to be ashamed to get tested. The tools are here. The science is clear. What’s missing is the willingness to act - for yourself and for others.