The Most Common STIs Of 2019 & How To Treat Them

If you’re sexually active, odds are likely that you’ll contract a sexually transmitted infection at some point in your life. One in two people will get an STI by age 25, according to the American Sexual Health Association. You can take actions, such as using condoms or dental dams and getting the HPV vaccine, to reduce the risk of catching an STI, but aside from total abstinence you can’t entirely eliminate that risk.

While there’s a lot of undeserved stigma around STIs, catching one doesn’t make you “bad” or “dirty” — you’ve simply caught an infection. As OB/GYN and writer Jen Gunter, MD, asserted in a New York Times column earlier this year, “Having an STI should have the same stigma as having influenza, meaning none.”

If you do have an STI, it’s important to know so that you can begin treatment — left untreated, STIs can lead to issues like chronic pain, pelvic inflammatory disease (when bacteria spreads throughout the pelvic region), chronic pelvic pain, infertility, and an increased risk of contracting other STIs. Planned Parenthood recommends that everyone get tested for STIs at least once a year, even if you’re in a monogamous relationship. And if you’re not in a monogamous relationship, Planned Parenthood advises also getting tested before having sex with a new partner. If you have multiple sexual partners, doctors recommend a more frequent testing schedule, at least once every six months.

In October, the Center for Disease Control and Prevention released a new report on STI prevalence. However, the CDC doesn’t track all STIs, only “nationally notifiable conditions” — infections that doctors are required to report. (Apart from certain STIs, that list includes Lyme disease, salmonella, and rubella.) This means that there are some very common STIs — including HPV and HSV — that the CDC doesn’t track year-to-year. We’ve included information on both here.

The CDC’s 2018 STD Surveillance Report found that reports of chlamydia, gonorrhea, and syphilis reached an all-time high. In response, the CDC urges for healthcare providers to make STI screening and treatment a standard part of medical care. The CDC also stressed the responsibility of state and local health departments to strengthen public health infrastructure and ensure that vulnerable populations have access to resources.

According to the CDC, in 2018, 1.8 million cases of chlamydia were reported, an all-time high and a 19% increase since 2014. Girls and young women ages 15 to 24 accounted for 44% of reported cases. Chlamydia is curable, and it’s treated with either a single dose or a seven-day course of antibiotics. Chlamydia can cause abnormal discharge, burning while urinating, or rectal pain, but most people with the STI don't experience symptoms.

In 2018, the CDC tracked 583,405 cases of gonorrhea. That's a 63% increase since 2014 and the highest number reported since 1991. Gonorrhea diagnoses increased among both men and women, but the increase was more significant for men, particularly for men who have sex with men. Like chlamydia, gonorrhea often presents without symptoms. People who do experience them might notice burning during urination, increased vaginal discharge, white, yellow, or green discharge from the penis, or spotting between periods, or swollen or painful testicles.

Gonorrhea is curable, and it’s treated with a single dose of two separate antibiotics. Rarely, untreated gonorrhea can spread to other parts of the body, which can be potentially fatal.

The CDC tracked 35,063 cases of of primary and secondary syphilis in 2018, increasing 34% for women and 11% for men compared to 2017. However, men accounted for nearly 86% of primary and secondary syphilis cases, with men who have sex with men accounting for 54% of all syphilis cases. Syphilis is curable, and it’s typically treated with a series of three penicillin injections. The most common symptom of primary syphilis is one or more sores at the site of infection; without treatment, it develops into secondary syphilis, which is characterized by a fever, rash, and swollen lymph nodes. In rare cases, if the condition still goes unchecked, it could develop into tertiary syphilis, which can lead to severe medical problems affecting other areas of the body, including the heart and brain.

The CDC also tracked 1,306 cases of congenital syphilis (syphilis passed from parent to child during pregnancy), including 94 infant deaths. Congenital syphilis increases the risk for miscarriage and stillbirth and can have a major health impact on infants, including premature birth, severe anemia, and brain and nerve problems. “Every single instance of congenital syphilis is one too many when we have the tools to prevent it,” Gail Bolan, M.D., Director, Division of STD Prevention, wrote in a press release. Dr. Bolan urged for an increase in syphilis testing, particularly for pregnant individuals.

Although the CDC doesn’t track the number of human papillomavirus cases reported every year, they estimate that nearly 80 million Americans have HPV, and an additional 14 million contract it each year. HPV can’t be cured, but in most cases, it goes away on its own without causing any health problems. However, in some cases, it can lead to issues including genital warts and certain types of cancers. 

Getting vaccinated can lower your risk of contracting HPV, as can using condoms during sex. For people with HPV, routine Pap smears can identify precancerous cells that can then be removed. If genital warts develop, they can be treated with prescription medication or removed by a healthcare provider.

The herpes simplex virus (HSV), has two strains: HSV-1 and HSV-2. Either strain can develop either orally (think: cold sores) or genitally (blisters around the genitals or rectum), although it’s rare for HSV-2 to develop orally. According to the CDC, more than one in six Americans has genital herpes, and the American Sexual Health Association reports that over 50% of Americans have oral HSV. 

There is no cure for herpes, but medication can prevent or shorten outbreaks and reduce the risk of transmission. People with herpes can take these medications either as episodic treatment, in which medication is taken at first sign of an outbreak, or as suppressive therapy, in which medication is taken daily in order to prevent outbreaks and reduce transmission risk.

The CDC estimates that about 3.7 million people in the U.S. have trichomoniasis. It's the most common curable STI, and it's caused by a parasite. About 70% of people with trichomoniasis do not show symptoms, however, so it’s difficult to know if those prevalence numbers are accurate. Those who do experience symptoms may notice itchy or irritated genitals; discomfort or burning during urination; and a change in discharge. Trichomoniasis is more common in women, though all genders can contract it. It’s treated with a single-dose antibiotic.