The Rise of Chlamydia in the US

Introduction

In general, sexually transmitted diseases (STDs) are becoming more and more common in the US. Chlamydia is the most common bacterial STD in the US, with more than a million cases reported each year. Rates have more than doubled since 2000, with the majority of cases occurring among younger people. Chlamydia causes no symptoms in more than half of those who are infected, but if left untreated, it can lead to long-term complications, including permanent infertility.

Sex is a significant part of many people’s lives. Knowing more about the risks can help you to protect yourself and stay as safe as possible while enjoying sex. How have chlamydia rates been changing in the US in recent years, and how can you best protect yourself?

Key Statistics and Trends

Overall Increase in Chlamydia Cases

Over the past few years, the incidence of chlamydia has generally been rising. In the 2021 CDC report on chlamydia (the most recent year for which statistics are available), there were 1.64 million new cases diagnosed in the US. This represents about a 4% increase in chlamydia rates in one year.

Between 2017 and 2021, the reported number of chlamydia infections actually dropped slightly. The rates rose in 2018 and again in 2019, but there was a drop in 2020, before rates rose again in 2021. However, as will be discussed later in this article, experts believe that this doesn’t actually represent a true decrease in the rates of chlamydia in 2020, but a decrease in reporting related to the pandemic.

In fact, since 2000, there has been a dramatic chlamydia rise in the US. The overall rate of chlamydia has doubled in that period of time. 

Disparities and High-Risk Groups

In general, younger people are at a higher risk for STDs. Chlamydia in young adults and teens is much more common than in older people. In fact, approximately two-thirds of all chlamydia infections occur in people who are 24 or younger. 

In addition, STDs, including chlamydia, are far more common in gay and bisexual men than in heterosexual men. However, women are at a slightly higher risk than men overall. In addition, there are racial disparities, with Black people being at about six times the risk of White people. Native and Latinx people are also at an increased risk.

Underlying Causes and Concerns

Impact of the COVID-19 Pandemic

While people were under lockdown for the COVID-19 pandemic, they may have had less access to new sexual partners than usual. This might be expected to lead to a decrease in chlamydia rates.

In 2020, the reported rates of chlamydia did decline somewhat. In 2021, the rates rose again by 4%. At first glance, this seems to indicate that the pandemic did decrease the rates of transmission. However, many experts believe that the true rates of chlamydia actually continued to rise in 2020 – even though the reported rates of chlamydia declined.

Part of the reason for this is that the pandemic caused many people to miss their routine healthcare visits. Many people receive regular chlamydia screenings at these appointments, and may therefore have missed getting tested in 2020. These cases would therefore go undetected. Some people also chose to use home STD testing during the pandemic, instead of visiting a doctor for testing. Most cases of chlamydia detected on home testing would not be reported to public health authorities, so they would not show up in the statistics. As a result, the officially reported rates of chlamydia would appear to be lower, even though the true number of infections was actually rising.

Behavioral Changes and Condom Use

In addition to creating social distance, the pandemic may have affected people’s behavior in other ways. Studies have shown that condom use declined significantly during the pandemic. Public health clinics, which usually distribute condoms to many people, may have been closed or had reduced hours. People were generally also going to stores less often during the pandemic, and could not always find what they were looking for even when they did get to the store. Because of these factors, they may not have had access to condoms. 

There are also other factors that could make people less likely to use condoms. One major factor is that chlamydia doesn’t always have symptoms. In fact, about 50% of chlamydia infections in men, and 70 to 75% in women, are asymptomatic. Because of this, many people with chlamydia are not even aware that they have it. They may falsely believe that since they don’t have any symptoms and neither does their partner, this means that neither person has an STD, and they don’t need to use a condom.

Condom use has been declining overall. In 2011, 75% of men reported using condoms, but in 2021, this had declined to only 42% of men. Although pandemic-related issues may have contributed, the pandemic doesn’t appear to be the only factor leading to a decline in condom use.

Chlamydia infections can still be transmitted even by people who don’t have any symptoms. In addition, untreated chlamydia can cause serious long-term effects – including permanent infertility – even if you don’t have any short-term symptoms. This is why condom use is so important, even when you and your partner feel completely healthy.

Conclusion and Recommendations

If you have sex outside of a mutually monogamous sexual relationship, it’s very important to use condoms every time you have sex, including vaginal, oral, or anal sex. This is true even if your partner doesn’t have any symptoms of an STD. Chlamydia very often doesn’t cause any symptoms, and there is a link between chlamydia and reproductive health issues like infertility, even if there are no immediate symptoms of the infection. Consistently using condoms will help to keep you protected.

In addition, it’s important to receive regular chlamydia screening. Because chlamydia often causes no symptoms, you won’t know whether you have it unless you get tested. You can visit your doctor or an STD clinic to get tested, or you can order a home testing kit for more privacy and convenience. 

Chlamydia can be treated with antibiotics. It’s important to receive treatment to avoid the risk of long-term complications like infertility, and to ensure that you don’t pass on the infection to others. Practicing safe sex will help to reduce your risk of getting chlamydia, and regular testing will ensure that you get the right treatment in case you do get infected.  

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