The Rising Tide of STIs in Tennessee: A County-by-County Look at a Growing Public Health Concern

Tennessee's sexual health numbers are telling two different stories at once. Chlamydia and gonorrhea, the state's most common reportable infections, have actually been easing off their pandemic-era highs for three straight years. Syphilis has done the opposite, climbing every single year since 2019, and HIV has quietly become a crisis concentrated almost entirely in a handful of counties — Shelby chief among them. This report walks through what the Tennessee Department of Health's own 2023 surveillance data says about Nashville, Memphis, Chattanooga, and Knoxville, why the picture changes so much depending on which corner of the state you're in, and what that means if you live, work, or are just passing through any of them.

Common STIs and HIV in Tennessee

Four infections drive almost every conversation about sexual health in this state right now.

• Chlamydia is Tennessee's single most-reported infection, and it's also the quietest — most women and roughly half of infected men never notice a symptom, so it spreads for months before anyone gets treated.
• Gonorrhea hits younger Tennesseans hardest, and it's the one epidemiologists watch most closely, since drug-resistant strains are becoming harder to treat with the antibiotics doctors have relied on for decades.
• Syphilis is the infection actually driving Tennessee's numbers upward, and its most devastating form isn't in an adult at all — it's congenital syphilis, passed from an untreated mother to her baby.
• HIV in Tennessee is really a story about geography — the statewide rate looks moderate until you isolate Memphis and Nashville, where the burden is several times the state average.

Statewide Trends: A Five-Year Look at the Numbers (2019–2023)

Tennessee's own health department tracks these three conditions by law, and its most recent report (covering 2019 through 2023) shows chlamydia rates sliding from 605.0 to 523.6 cases per 100,000 residents, and gonorrhea falling from 235.3 to 190.9. Syphilis went the other direction entirely — from 32.6 cases per 100,000 in 2019 to 57.2 in 2023, a 75% jump, with the state flagging a 6.3% increase in just the last year of that window alone.

Nationally, Tennessee's overall chlamydia rate ranks 35th among states and its congenital syphilis rate ranks 37th, according to America's Health Rankings' analysis of CDC data — not the worst in the country, but not reassuring either, especially given how fast the syphilis trendline is moving compared to most other states that are further along in bringing their outbreaks down.

HIV in Tennessee: Ground Zero in Memphis

Nine hundred and eight Tennesseans were newly diagnosed with HIV in 2023 — a 17% increase from the 773 diagnosed back in 2019 — and the state now has 21,577 residents living with a diagnosis, up 19% over that same stretch. The Department of Health estimates another 4,400 people are living with HIV and don't know it yet. The disparities inside those numbers are stark: non-Hispanic Black Tennesseans are diagnosed at a rate 8.4 times higher than white Tennesseans, a gap that tracks closely with what we've written about elsewhere regarding HIV risk across racial groups nationally.

But the real story is geography. Shelby County — Memphis — accounted for 39% of every single new HIV diagnosis reported statewide in 2023, with Nashville's Davidson County adding another 17%. Local health officials in Memphis have said that in 2023, the metro area recorded the highest HIV incidence rate of any metropolitan area in the entire United States. New diagnoses in Shelby County climbed from 258 in 2017 to 352 in 2023, and among 15-to-19-year-olds specifically, the county's HIV rate rose 40% while its teen syphilis rate rose more than 150% over roughly the same period. We go deeper into what's behind that in our full Shelby County analysis. For anyone weighing their own risk, PrEP and PEP remain the most effective prevention tools available, and neither requires a positive test first.

Nashville, Memphis, Chattanooga & Knoxville, Side by Side

Tennessee's health department breaks its surveillance down by public health region, which lines up almost exactly with the state's four largest cities. Here's how 2023 looked across all three reportable STIs plus HIV:

*Cases per 100,000 residents, 2023. Knox County did not rank among Tennessee's four highest-burden counties for HIV, so no county-specific rate was published for it individually. Source: Tennessee Department of Health, 2023 STI and HIV Epidemiological Profiles.

The HIV numbers follow a similar pattern once you look past the big four cities. Shelby County's rate of 828.4 persons living with diagnosed HIV per 100,000 residents is the highest in Tennessee, but rural Lake County (769.2) and Haywood County (548.0) both outrank Nashville, Chattanooga, and Knoxville. HIV in Tennessee isn't purely an urban story — it's concentrated wherever poverty, limited healthcare access, and thin public health infrastructure overlap, and that happens in small West Tennessee counties just as often as it does in Memphis proper.

What's Driving Tennessee's Numbers

No single cause explains a trend this size, but a few factors keep showing up across the state's own reporting and local news coverage:

• A rural-heavy public health system. Only six of Tennessee's 95 counties run their own metropolitan health department; the other 89 are grouped into just seven regional offices, which stretches testing, contact tracing, and follow-up care thin outside the big cities.
• Stigma in smaller communities. Confidentiality worries are a bigger barrier in a county of 15,000 people than in Memphis, where nobody at the pharmacy counter knows your name.
• Dating apps and casual encounters. Public health officials nationally, and in Tennessee specifically, keep pointing to the same shift in how people meet partners — we cover the mechanics of that in our piece on dating apps and STD risk.
• Substance use. The state's own HIV report found that 1 in 10 people newly diagnosed in 2023 reported injection drug use as a risk factor, and methamphetamine and opioid use keep surfacing in county-level syphilis investigations.
• Economic pressure. Tennessee's median household income ($67,097) sits well below the national figure ($78,538), and its poverty rate (14%) runs above the national average — both of which correlate with delayed care and missed screenings.
• Gaps in sex education. Tennessee law requires an abstinence-focused curriculum in most districts, which leaves plenty of young adults without a clear picture of transmission risk or where to get tested confidentially.
• Antibiotic-resistant gonorrhea. A national concern that's just as relevant in Nashville as it is in New York — resistant strains mean treatment increasingly has to be more aggressive and more closely monitored.

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