Can an STI come back after treatment?

Many people who get treated for an STI often wonder if their infection can come back, even after it’s been treated. It makes sense: you can get a cold or the flu more than once, so why not an STI?

In this article, we’ll discuss what STIs are, how they are transmitted, how they are treated, and how STIs can come back. We’ll also talk about which STIs can come back even after treatment. Whether you want to learn more about STIs or are concerned about a recent infection, this post has everything you need to know. It’s important that both you and your partner are involved in STI prevention and treatment to reduce the risk of recurrence.

What are STIs?

STIs are infections that typically pass from one person to another through sexual contact. These infections can affect both men and women, and they can have serious health consequences if left untreated.

Symptoms of STIs can vary widely, and many people may not experience any symptoms at all. For example, a Chlamydia infection is often silent and can only be detected through an STI test. This is why regular testing is crucial, even if you feel healthy. STIs can be transmitted through sexual activity, including vaginal sex, oral sex, and anal sex. Even skin to skin contact can transmit some infections, like HPV. Anal sex, in particular, can facilitate the transmission of bacteria, viruses, or parasites through contact with infected bodily fluids, increasing the risk of certain STIs.

Can STIs “come back” after treatment?

Yes, STIs can “come back”, so to speak. This can happen in a few ways: through reinfection, unsuccessful treatment, or recurrent outbreaks.

Reinfection

Reinfection basically refers to getting the same infection twice. The first infection has been cleared, but then something happens (usually, sex) that causes you to get the infection again.

Unsuccessful treatment

Unsuccessful treatment usually occurs when the patient takes their medication incorrectly or doesn’t take their full dose.

This incredibly common occurrence is actually responsible for the rise in antibiotic-resistant STIs. These STIs have built up an immunity to the antibiotics that are usually used to treat them, requiring more powerful drugs and therapies. Mycoplasma genitalium is another bacterial infection that can be challenging to treat due to antibiotic resistance, underscoring the importance of proper testing and guided therapy.

Outbreaks

Some viral infections can come back in the form of outbreaks. Herpes outbreaks are recurrent episodes of sores or blisters caused by the Herpes Simplex Virus (HSV) reactivating periodically from its dormant state in nerve cells.

Viral infections like Herpes and HIV don’t ‘come back’ via reinfection but remain dormant and can reactivate due to various triggers.

Which STIs can come back after treatment?

Chlamydia, Gonorrhoea, Syphilis, and other bacterial infections can usually be cured with antibiotics. However, you can get reinfected with these pathogens, even after they’re cured.

Studies show that the chance of testing positive for any STI again within six months after treatment for a bacterial STI is nearly 25%. Chlamydia reinfection rates are about 17% to 20% within a few months, and Gonorrhoea reinfection rates are roughly 14% within six months.

Some of these symptoms may persist after treatment or wax and wane. This doesn’t mean the infection has come back; it just means the damage hasn’t healed properly.

Dr. Steve Chapman, expert in infectious disease and internal medicine

In cases of advanced Syphilis, the course of antibiotics may have been too short, and a few hidden bacteria slowly start to reactivate months later. Having a healthy immune system can improve the effectiveness of treatment and help the body fight off syphilis more effectively.

Dr. Steve Chapman, an expert in internal medicine and infectious disease, had this to say about how and why STIs keep coming back:

“Some symptoms that we have with infections [like Chlamydia] ([pus], pain, etc) are a result of the damage the bacteria does. Some of these symptoms may persist after treatment or wax and wane. This doesn’t mean the infection has come back; it just means the damage hasn’t healed properly.

“In the case of HPV (human papillomavirus), we are able to expel the virus from our bodies once the immune system has peaked. This generally means that once we have kicked out a strain of the virus, we will not see that particular one again on the test. But occasionally it was actually just ‘deep seated’ into tissues like the cervix and slowly appeared again. Luckily, it wasn’t doing any damage in that dormant state.”

It’s important to manage these infections with medication and regular testing to ensure the health and wellbeing of you and those you care about.

How are STIs treated?

Antibiotics or antiviral medications usually result in a successful treatment of most STIs. These drugs are usually administered orally or through injection. STI treatment is most effective when both partners are tested and treated simultaneously to prevent reinfection.

It is important to wait until both partners have completed treatment before resuming sexual activity. Completing treatment helps prevent future infections and reduces the risk of ‘ping-pong’ transmission, in which the infection is passed back and forth. The most common cause of reinfection is sexual contact with an infected partner who has not been treated.

In some cases, such as with Herpes, these infections live in the body permanently, and medication is used to manage symptoms. It’s important to get tested for STIs if you suspect that you may have been infected. The earlier an infection is diagnosed, the easier it is to treat.

Final thoughts

STIs can indeed come back, even after they are treated. If you suspect that you may have an STI, don’t wait to get tested. If you’re sexually active, getting tested regularly can prevent serious health consequences down the road. Early detection of these infections is key.

Don’t leave your sexual health to chance.

This article first appeared on 01/09/2023. Last updated 06/03/2026.

This article was medically reviewed by Dr. Steve Chapman, 04/03/2025.

---