Maryland frequently ranks among the U.S. states with the highest prevalence of sexually transmitted diseases (STDs), such as chlamydia, gonorrhea, syphilis and others. And the frequency of STDs in Maryland, like much of the rest of the U.S., is on the rise for many types of sexually transmitted infections.
Which STDs are the most common here in Maryland, how has the prevalence of certain diseases changed over time, and which locales in the state have the highest rates of STDs? To understand the picture of sexual health in Maryland, we’ll dig into data from the federal Centers for Disease Control and Prevention and the Maryland Department of Health.
Chlamydia Rates in Maryland
Maryland ranks just outside the top 10 when it comes to the population-adjusted rate of chlamydia, and more than 30,000 people in Maryland were diagnosed with chlamydia in 2018. The rate of chlamydia infections in Maryland is about 10% higher than the national rate.
Chlamydia infections per 100,000 people
Maryland’s rate of chlamydia had remained relatively steady for a few years, but it’s gone up every year since 2014 and increased by more than one-third between 2008 and 2018.
Maryland chlamydia rate by year (cases per 100,000 people)
Six of the 10 states with the highest rates of chlamydia are in the South, and Maryland’s rate places the state in the top half regionally.
Chlamydia infection rate, Southern states (cases per 100,000 people)
Gonorrhea Rates in Maryland
Maryland’s population-adjusted rate of gonorrhea infections is slightly below the national rate, but the state ranks in the top half among all states.
Gonorrhea infections per 100,000 people, top 25
Bucking national trends, gonorrhea has become less prevalent in Maryland over the past year, but the disease still has seen a huge increase in the past decade, with the rate increasing almost 44% between 2008 and 2018.
Maryland gonorrhea rate by year (cases per 100,000 people)
Thanks in part to the one-year decline in gonorrhea, Maryland ranks in the bottom half of the Southern region with a rate that’s just under half that of the region’s leader, Mississippi.
Gonorrhea infection rate, Southern states (cases per 100,000 people)
Syphilis Rates in Maryland
Maryland has the sixth-highest population-adjusted rate of primary and secondary syphilis infections in the country with a rate that’s more than 25% higher than the overall U.S. rate.
Primary and secondary syphilis infections per 100,000 people
The rate of primary and secondary syphilis infections in Maryland has gone up every year since 2012 and over the past decade, the rate has nearly doubled.
Maryland primary and secondary syphilis rate by year (cases per 100,000 people)
Southern states make up 60% of the 10 states with the highest syphilis rates, and Maryland is third overall in the region.
Primary and secondary syphilis infection rates, Southern states (cases per 100,000 people)
HIV & Other STD Rates in Maryland
More than 1,000 people were newly diagnosed with HIV in Maryland in 2017, and the state’s population-adjusted rate is the fourth-highest in the country. But in a bit of good news, Maryland posted a nearly 10% decrease in HIV prevalence between 2016 and 2017. See HIV test options.
Hepatitis B & C
Acute infections of both hepatitis B and hepatitis C are lower in Maryland than the rest of the country, and hep B infections have declined dramatically in recent years. Acute hep B cases dropped by more than 50% between 2012 and 2016, while acute hep C infections fell by about 14% in the same time period. See hepatitis test options.
In addition to being the most common STD in the world, human papillomavirus also causes the vast majority of several types of cancer, including cancers of the cervix, penis, anus and vulva. Pinpointing how many people at any given time have HPV is quite difficult because most cases do not cause any obvious symptoms, but understanding the rate of HPV-causes cancer can paint at least part of the picture. Maryland’s rate of HPV-caused cancer is about 8% lower than the national median, and Maryland’s rate is the nation’s 11th-lowest. See HPV test options.
STDs in Maryland Cities & Counties
Cases of chlamydia, gonorrhea, and primary and secondary syphilis are much more common in Baltimore than in the rest of the state, and the city makes up a huge percentage of cases of all three STDs, though a few other areas of the state also have higher rates of certain diseases.
Baltimore County and the city of Baltimore combined to account for more than one-third of all infections of primary and secondary syphilis in Maryland in 2017.
Maryland counties by chlamydia infection rate (cases per 100,000 people), top 10
About 2 in 5 gonorrhea infections in Maryland in 2017 were diagnosed in people living in the city of Baltimore.
Maryland counties by gonorrhea infection rate (cases per 100,000 people), top 10
Primary and secondary syphilis
The city of Baltimore and Baltimore County combined to account for nearly half of all syphilis infections in 2017.
Maryland counties by primary and secondary syphilis infection rate (cases per 100,000 people)
Maryland ranks relatively highly when it comes to how common sexually transmitted disease are in our state. But as the decline in the prevalence of both gonorrhea and HIV shows, it’s possible to make progress against such infections. Getting yourself tested to make sure you aren’t unknowingly passing along a sexually transmitted infection is a smart first step.
- Maryland Department of Health, Center for STI Prevention, Sexually Transmitted Infections, 2018 Annual Report. (2019). Retrieved from https://phpa.health.maryland.gov/OIDPCS/CSTIP/CSTIPDocuments/Reports/STI%202018%20Annual%20Report%20Maryland.pdf
- Centers for Disease Control and Prevention, HIV Surveillance Report, Diagnoses of HIV Infection in the United States and Dependent Areas, 2017. (2018). Retrieved from https://www.cdc.gov/hiv/pdf/library/reports/surveillance/cdc-hiv-surveillance-report-2017-vol-29.pdf
- Centers for Disease Control and Prevention, Sexually Transmitted Disease Surveillance 2017. (2018). Retrieved from https://www.cdc.gov/std/stats17/SRtables.pdf
- Centers for Disease Control and Prevention, HPV-Associated Cancer Rates by State, 2011-2015. (2018). Retrieved from https://www.cdc.gov/cancer/hpv/statistics/state/index.htm
- Centers for Disease Control and Prevention, Surveillance for Viral Hepatitis – United States, 2016. (2018). Retrieved from https://www.cdc.gov/hepatitis/statistics/2016surveillance/index.htm
Note: Some states have published more recent data for chlamydia, gonorrhea, and primary and secondary syphilis. For states in which that’s the case, we have substituted the individual state data for 2018 and used that in our rankings, while other states’ rankings are based on 2017 numbers. In some cases, we assume that when the full national dataset that includes 2018 is published by the CDC, states’ positions relative to other states will change, though those changes are unlikely to be dramatic, since the CDC data comes from the states.