Medically reviewed on April 24, 2023 by Morgan Spicer, Medical Communications Manager. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.
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Sexually transmitted infections (STIs), also known as sexually transmitted diseases (STDs), refer to over 30 different bacteria, parasites, and viruses frequently known to be transmitted through sexual contact.  Some STIs are also transmitted from mother to child during breastfeeding, childbirth, or pregnancy. The eight most common STIs include :
Anyone that is sexually active should be knowledgeable about the risk and prevalence of these infections. Preventing STIs can be done through abstaining from sexual activity, reducing your number of sexual partners, using barrier methods such as condoms, and getting vaccinated when possible for viruses such as HPV and hepatitis B. 
STI trends naturally rise and fall. In the past two decades, the United States saw a historic low of gonorrhea cases in 2009, which began increasing up to 82.6% in 2018.  Chlamydia is generally more common than gonorrhea, with rates also increasing in the United States since 2009.  Syphilis rates have also jumped significantly in recent years. Rates reached a low in 2000 with only 2.1 reported cases per 100,000 people, and increased to 4.5 cases per 100,000 in 2010.  The largest increase in syphilis rates in decades was noticed recently, following the SARS-CoV-2 pandemic. 
Read about STD rates by state
Anyone that is sexually active is at risk of contracting an STI. Having open and honest conversations with your current sexual partners, using condoms or dental dams, and getting tested frequently are all great ways to reduce the risk of contracting or spreading an STI.  Research shows that some communities are disproportionately impacted by STIs, including men who have sex with other men, young people, and people of color. 
In recent years, experts have been focusing on the dramatic rise in many STI rates during and following the COVID-19 pandemic. The CDC found that the number of syphilis cases jumped 32% from 2020 to 2021 and increased 74% since 2019, and chlamydia and gonorrhea rates each increased around 4% from 2020 to 2021.  It should be noted that many experts are concerned of underreporting during these years due to changes in screening and in-person visits.  This is a result of shelter-in-place orders, disrupted prevention and care activities, and the redirection of many resources and staff members to aid in pandemic related care. Additionally, many STIs, including chlamydia and gonorrhea are often asymptomatic, leading fewer people to seek out testing or to be diagnosed during virtual or telehealth screenings. 
So what is driving the increase in STI cases, and what did the pandemic have to do with it? It’s estimated that the lack of in-person healthcare visits and STI testing played a role in the increased spread of STIs.  Additionally, many of those who are disproportionately affected by STIs are less likely to access regular medical care, or may be afraid of facing discrimination and stigma.  There are also many socioeconomic factors that impact someone’s ability to seek out medical care or preventative testing, including poverty and health insurance status.
In general, STIs can be easily spread, especially when asymptomatic. Chlamydia and gonorrhea are two commonly asymptomatic STIs, leaving many to go untreated for long periods of time and potentially spreading an infection to multiple partners.  STIs such as syphilis are more likely to cause noticeable symptoms and cause those who have infections to seek out medical care.
Unfortunately the most recently available national STD data is limited to 2021.  The director of CDC’s Division of STD Prevention did suggest that the STI epidemic shows no signs of slowing for a while without long-term innovations in STI prevention, diagnosis, and treatment.  Current efforts are focused on the use of doxycycline, an antibiotic, as a post-exposure drug after having sex—similar to a “morning after pill” for STIs. 
Many people with STIs have no symptoms and can unknowingly pass on an infection. Those who do experience signs of an STI may notice the following :
While there has been an increase in multiple STIs following the pandemic, the United States is experiencing a surge in syphilis cases since 2019.  Syphilis is caused by a bacterium known as Treponema pallidum and is most often spread via vaginal and anal sex.  The first symptom of syphilis is usually a painless sore found on or near the genitals, rectum, or mouth. Not everyone notices this sore as it is often painless and can be hidden inside the rectum or vagina. There are multiple stages of syphilis and symptoms can vary with each stage. Some common signs of syphilis are :
Untreated syphilis may cause more serious complications involving the nervous system, cardiovascular system, eyes, bones, and joints. Fortunately, early stage syphilis can be cured with a penicillin injection, but prompt treatment is necessary when attempting to avoid damage from later stages of syphilis.  This is why following recommended screening guidelines is important.
If you are concerned about your sexual health, you may want to consider getting tested. It’s recommended that all sexually active people be tested for STIs at least once a year; some may benefit from more frequent testing depending on the number of sexual partners and type of sexual activity.  There are options available to test yourself for STIs in the comfort of your own home. The Everlywell Female STD Test and Male STD Test both come with everything you need to collect a sample, send your sample to the lab, and view your results at home. If you do need treatment, you can connect with a healthcare provider to discuss your options.