STIs are on the Rise in the US: Learn Symptoms, Treatments & How to Protect Yourself

By Ananya Vaidya
Medically reviewed
July 22, 2021

STIs and STDs like chlamydia, gonorrhea, and herpes affect 1 in 5 Americans. Most people do not feel any symptoms when they are infected with an STI, which means they are unlikely to get tested. This can result in the infection being spread to their sexual partners, and can have longer-term effects on their health.

STIs are shrouded in stigma, but all STIs can be treated and many can be cured completely. Find out more about STIs, their symptoms, and your prevention and treatment options in this article.

What are STDs and STIs?

STIs, or sexually transmitted infections, are infections that you can get through unprotected sex. STI is often used interchangeably with STD (sexually transmitted disease), but they are not the same.

While all STDs begin as STIs,  not all STIs progress into STDs. An example of this is human papillomavirus, commonly known as HPV. Often, HPV goes away on its own, making it an STI, but if it progresses into genital warts or cervical cancer, it becomes an STD.

There are over 25 infectious organisms that can lead to STIs, and these organisms can cause many different clinical conditions, from herpes to pubic lice.

STIs are extremely common—most people who are sexually active will have one in their lifetimes, and they are the most commonly reported infection in the United States. All STIs can be treated, and many can be completely cured, which is why, if you are sexually active, it is important to get tested regularly.

Despite their prevalence, stigma can make being diagnosed with an STI or considering getting tested for one extremely scary, but this is absolutely not the case. Here, we will help you learn more about STIs—their symptoms, how to prevent them, and treatment options available to you if you have been diagnosed with one. We will also discuss what to do if you think you have an STI.

STIs are on the Rise—Who is at Risk?

In 2019, the CDC reported that reported STIs reached an all time high for the sixth year in a row, and they estimate that 1 in 5 people have an STI.

Chlamydiagonorrhea, and syphilis are the three most commonly reported STIs in the United States. Since 2015, there has been a nearly 20% increase in reported cases of chlamydia, over 50% increase in reported cases of gonorrhea, and an over 70% increase in reported cases of syphilis.

While STIs can affect anybody, some communities, such as communities of color, are particularly at risk. Due to disparities in healthcare access and education, Black, Latinx, and Native populations are more likely to be diagnosed with an STI.

When it comes to Chlamydia, the most commonly reported STI in the US, Black people are 8.9 times more likely to be diagnosed; Native Americans are 3.7 times more likely to be diagnosed; and Latinx people are 1.9 times more likely to be diagnosed with Chlamydia than their White counterparts.

Other groups who are particularly at risk are men who have sex with men and transgender women. 

Furthermore, of the roughly 20 million new cases of STIs that occur annually in the US, around half of them are amongst adolescents and young adults aged 15 to 24.

In fact, it is estimated that 1 in 4 sexually active females in this age range have an STI.

This is largely because adolescents’ are more likely to engage in risky sex, this could be due in part to their prefrontal cortexes (the part of the brain responsible for executive functions like predicting the consequences of your actions) is still developing.

Adolescents are also less likely to use sexual health services, so they are less likely to become aware they have an STI or seek treatment. Adolescent females are also particularly susceptible to STIs like HPV and Chlamydia as they do not produce as much cervical mucus as an adult.

Women are also more susceptible to STIs than men are. This is in part due to biology—the lining of the vagina is easier to penetrate than the skin of the penis, and the vagina is a good environment for bacteria to grow.

Women are also less likely to have symptoms of an infection, and when they do, they are more likely to dismiss symptoms like discharge as something other than an STI, so they may be less likely to get treated.

Pregnant women can pass on STIs to infants. Congenital syphilis––that is, syphilis present from birth––has seen a 269% increase since 2015. STDs like trichomoniasis passed down to infants can cause stillbirths, bone deformity, severe anemia, and brain and nerve problems.

What are the Symptoms of an STI?

While many people associate STIs with pronounced, visible symptoms like ulcers and warts, this is not always or even usually the case. In fact, 90% of people infected with an STI have no symptoms at all. While it is highly common to  contract an STI without any symptoms, common symptoms can include:

  • Painful urination
  • Discharge from the vagina or penis—this is often cloudy or bloody
  • Ulcers or warts in the genital, anal, or perianal areas
  • Swollen lymph nodes
  • Itching or irritation, especially in the genital or anal areas
  • Fever
  • Fatigue
  • Rashes on any part of the body

More specifically, symptoms in women can include:

In men, symptoms can look like:

  • Testicular pain
  • Swollen or painful testicles
  • Burning inside the urethra
  • Painful ejaculation

Preventing STIs

While the only way to prevent STIs is to not have vaginal, anal or oral sex, there are precautions that you can take to reduce your chances of getting an STI. This involves having sex with one monogamous partner, or reducing the number of sexual partners you have.

You can also receive a vaccination to prevent HPV (if you are at or below the age of 26) or hepatitis B. Furthermore, you can take PrEP (Pre-exposure Prophylaxis) to reduce the risk of HIV infection. 

Engaging in safe sex can also help reduce the risk of infection. Safe sex practices include:

  • Correctly using a condom, dental dam, or latex gloves when having anal, vaginal or oral sex or during manual stimulation.
  • Avoiding sex while under the influence of drugs and alcohol.
  • Getting regualrly tested for STIs, especially when having sex with new or multiple partners.
  • Being open about your own STD status, your STI and sexual history, and your history of drug use, and encouraging your partner to do the same.
  • Completing your course of medication to treat an STI, or regularly following your treatment plan to manage it.

Treating STIs

STIs can be diagnosed and treated by your primary care provider, urgent care departments, emergency departments, gynecologists, as well as sexual health clinics like Planned Parenthood.

It is important to seek treatment if you suspect that you have an STI, because they can cause long term health problems if left untreated. Tertiary stage syphilis can lead to damage to the nervous and cardiovascular systems; HPV can lead to cervical cancer; and untreated STIs leave you more susceptible to getting HIV.

The CDC recommends annual screening for chlamydia and gonorrhea for sexually active young women. It is also recommended to screen for cervical cancer using a Pap test for all women from the age of 21.

Chlamydia and gonorrhea testing is also recommended in men who have sex with men. If you come into contact with HIV, take PEP (post-exposure prophylaxis) within 72 hours of infection to reduce your risk of infection.

When to See a Doctor

You should get tested for STIs after every time you have sex with a new partner, if your partner has sex with somebody else, or if you have STI symptoms.

It is important to go to the doctor even if you are not exhibiting symptoms as, in most cases, people infected with an STI are asymptomatic. 

How K Health Can Help

K Health provides a simple, accessible way to get help with an STI. Download the K Health app and check your symptoms, explore conditions and treatments for free, and if needed, speak to a doctor about next steps for as low as $12 a month. K Health’s AI-powered app is HIPAA compliant, and runs on 20 years of clinical data.

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.

Ananya Vaidya

Ananya Vaidya is an undergraduate student at Dartmouth College, where she studies psychology and English. As a K Health intern, she writes health guides on a variety of different topics. At university, she is involved in multidisciplinary research, a part of Dartmouth’s on-campus writing centre, and edits for multiple publications. In her spare time, Ananya enjoys reading and writing.