Sexually transmitted diseases are surging in America. The CDC explains what to look out for

Sex is more than just a pleasurable experience, it's an important part of one's mental and physical health. One of the essential elements of maintaining that health is monitoring for sexually transmitted infections (STIs). But the landscape of diseases that most people learned about in sex ed — if they had it at all — is changing, with new conditions emerging without the same level of surveillance for things like gonorrhea and syphilis.

Even with advances in treatment and contraception, Americans have been experiencing a surge in STIs like chlamydia, gonorrhea and syphilis, all three of which saw significant increases between 2020 and 2021, the most recent year data is available. There are also relatively new or rare diseases circulating that some people may not have ever heard of in a sex ed class, such as Mycoplasma genitalium (Mgen for short), Shigella flexneri, Neisseria meningitidis and Lymphogranuloma venereum (LGV). But all of these can cause unpleasant infections spread through sexual activity.

Here's a few things most people should know about these illnesses and what to look out for.

01 Chlamydia

In November, the Food and Drug Administration (FDA) approved the first test ever for chlamydia and gonorrhea that has an at-home sample collection. Indeed, it is the first STD test with at-home sample collection ever authorized by the FDA except for a previous test used to detect HIV. While chlamydia and gonorrhea are not as severe as HIV, the former disease is certainly a menace.   Chlamydia symptoms include burning while urinating and suffering from discharge from your genitalia. Men can also suffer from pain and swelling in their testicles, while women can endure such damage to their reproductive systems that they are unable to successfully get pregnant later. Although it is difficult to account for many cases of chlamydia, as of 2018 the CDC estimated that there were four million cases of the disease in the United States. In 2021, there were a total of 1,644,416 confirmed cases has been reported to the CDC.

02 Gonorrhea

Although gonorrhea is often asymptomatic, it can also lead to symptoms in men such as a white, green or yellowish discharge from the urethra. For women, gonorrhea is either asymptomatic or has symptoms that can be mistaken for other diseases such as vaginal or bladder infections. If gonorrhea is contracted during anal sex, the symptoms can include discharge, itching and painful bowel movements, and if contracted during oral sex can lead to a sore throat.   Yet the real threat with gonorrhea is what it does to the body in the long-term: For women, gonorrhea infections can lead to pelvic inflammatory disease (PID) after spreading into the uterus or Fallopian tubes, leading to infertility. Men can also become infertile after contracting gonorrhea it is occurs in conjunction with epididymitis. Untreated gonorrhea can also cause a potentially fatal blood infection known as gonococcal infection (DGI). In 2021, 710,151 cases of gonorrhea were reported to the CDC, making it the second most prevalent STD after chlamydia.   While "regular" gonorrhea is bad enough, there is a growing issue with antibiotic resistant strains that don't clear up with typical medications. This means, there's a risk that one day in the future, we won't be able to shrug this disease off like we do with other relatively minor infections. Every time gonorrhea is treated with antibiotics, it can help the pathogen evolve ways of evading it.

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03 Syphilis

"Syphilis increases are particularly concerning, with a jarring 32% increase in a single year from 2020 to 2021," the CDC told Salon by email. They added that the most recent national data on the syphilis epidemic found that cases among newborns have increased by ten-fold in the past decade. In fact, a recent outbreak was even recorded in Houston, Texas.   "These cases are tied to increases in syphilis among reproductive-age women and their partners and are especially serious as they can result in tragic outcomes, like miscarriage, stillbirth, infant death and lifelong medical issues," the CDC explained. "These cases occur when mothers do not receive timely testing and treatment during pregnancy." Although syphilis had reached a historic low in 2000 and 2001, in 2021 176,713 cases of syphilis (all stages and congenital syphilis) were reported to the CDC.

04  Mycoplasma genitalium

Mgen, which is short for Mycoplasma genitalium, is a particularly ominous bug because of how difficult it is to treat. As of 2018, the overall prevalence of Mgen among people ages 14 to 59 was 1.7%, but that number is slowly but steadily rising. It's not typically screened for at many STI clinics or doctors offices. Since the bacteria lacks a cellular wall, it can ward off typical antibiotics that would otherwise stop it from reproducing. Even worse, the disease can lead to infertility, cervical inflammation, preterm birth and even miscarriage in women, as well urethral inflammation and infertility in men. Although scientists are not yet sure this disease can lead to infertility, it appears to be permanent.   "From 2017-2018, estimates were that nearly 2% of adults from ages 14-59 years had Mgen," the CDC wrote to Salon. "However, there were no FDA-approved diagnostics (tests) for Mgen until 2019."

05 Shigella flexneri

Shigella flexneri isn't always passed through sex. It is commonly contracted by young children, with an average of 28 cases per 100,000 in children younger than 4 years and 25 cases per 100,000 in 4 to 11-year-old children. It is the most common cause of diarrheal illness in children under 5 years old in Saharan Africa and South Asia.   As the CDC explained to Salon, this is not exclusively a sexually transmitted infection, but it can be spread through sexual contact. Its main symptoms include feverishness, stomach pain, feeling the need to defecate even when the bowels are empty, with prolonged or bloody diarrhea. There are a reported 450,000 infections involving various strains of Shigella in the United States every year, and in addition to sex it can be spread through contaminated water or food or by touching one's orifices after it gets on one's hands. It can also be spread through feces, such as someone being infected after changing a diaper from an infected baby. It can also spread through anal sex, with a 2023 review in the journal Sexually Transmitted Infections warning that oral to anal contact is especially risky.

06 Neisseria meningitidis

Neisseria meningitides is a nasty little bug that can cause meningitis, which can be deadly. has an incident rate of less than 1 out of 100,000 cases per year in the United States, but worldwide there are an estimated 1.2 million cases per year. As the CDC explained, this is not exclusively a sexually transmitted infection, though it can spread through the urethra and rectum, as exemplified by an outbreak in Vietnam earlier this year. Thankfully its numbers have been on the decline since the 1990s. The agency also reported that in 2019 there were only 375 total cases of meningococcal disease reported in the United States, or an incidence rate of 0.11 cases per 100,000 persons.   In cases of meningococcal meningitis, the main symptoms of the disease are headaches, feverishness and stiff necks; in cases of meningococcemia the symptoms include rashes and sepsis. Roughly 10 to 15 out of every 100 people who get diagnosed with this disease will die — many others will be left with permanent disabilities including deafness, nervous system problems, loss of limbs and brain damage.

07 Lymphogranuloma venereum

To better understand this condition, Salon reached out to Ronnie M. Gravett, MD, MSPH, an assistant professor of infectious diseases at the University of Alabama Birmingham's School of Medicine. He explained to Salon by email that it is difficult to know the prevalence of Lymphogranuloma venereum because the existing systems for monitoring diseases do not focus on LGV.   "Think of it this way: all LGV is caused by Chlamydia trachomatis, but not all chlamydia infections are cases of LGV," Gravett explained. "Although chlamydia is very common and reported in annual surveillance reports by the CDC, LGV is more rare than mucosal chlamydia, aka the 'regular' chlamydia." Public health officials currently can identify chlamydia on a larger public health scale, but cannot do so as of yet with LGV cases. LGV took off during the early days of the COVID-19 pandemic, when a total of 284 LGV cases were diagnosed (primarily among HIV patients and men who have sex with men).   According to Gravett, common symptoms of LGVB include discharge like pus, mucus and even blood from the anus and/or rectum. Occasionally this can also happen in the vagina or penis. "'Tenesmus,' or the sensation of anorectal fullness and discomfort, may also be present.   Importantly, LGV can cause an ulceration at the site of exposure, i.e., on the anal verge or higher up in the anus or rectum. Given its location, the ulcer may not ever be seen." He also noted that LGV is more invasive than traditional chlamydia, "so it can spread to lymph nodes and cause enlarged lymph nodes, which may or not be detected."

In addition to being aware of the details of these STDs, it is also important to be cognizant of which groups are more likely to be impacted by them. As the CDC told Salon by email, "While STIs are common in all U.S. regions and across all groups, some communities are hit especially hard. The 2021 data show STIs continue to disproportionately affect gay and bisexual men and younger people." The CDC added, "Additionally, a disproportionate number of cases were diagnosed among Black/African American and American Indian/Alaska Native people, groups more likely to face social conditions that make it more difficult to stay healthy."

As with any sexually transmitted disease, the best way to prevent them is to use condoms (if applicable) or practice safer sex. If you notice any unusual symptoms, especially related to the genitals, it's best to get a medical examination or an STI test. When caught early, most of these diseases are manageable. Because of taboos around sex, some people are embarrassed about STIs, but they're really just like any other form of illness. Taking it seriously and being diligent about it ensures that sex remains a pleasurable part of someone's lifestyle.