By the Editorial Team — referencing Dr. Jay K. Varma’s article on Healthbeat.org
Read more of Dr. Varma’s work at DrJayVarma.com

In a recent Healthbeat feature, physician and epidemiologist Dr. Jay K. Varma breaks down the latest CDC data on sexually transmitted infections — and what the numbers might not be telling us.

The CDC’s 2024 Sexually Transmitted Infections Surveillance Report suggested an encouraging trend: overall reported cases of chlamydia, gonorrhea, and syphilis declined by 9% from the previous year. It’s the third straight annual drop, and the first sustained multi-year decline in a decade.

But as Dr. Varma points out, the story isn’t so simple.

What the Numbers Seem to Say

The CDC data show:

• Chlamydia declined 8%
• Gonorrhea dropped 10% — its third year of decline
• Primary and secondary syphilis fell 22%
• Congenital syphilis, however, rose 1.6%, reaching nearly 4,000 cases — the twelfth consecutive annual increase

At first glance, this could look like long-awaited progress in sexual health. But as Dr. Varma explains, the reasons behind the changes — and what they might conceal — are just as important as the numbers themselves.

Why STIs Might Appear to Be Declining

Dr. Varma explores several possible reasons behind the apparent drop:

• More proactive testing and treatment through HIV PrEP programs, which require regular STI screening.
• The growing use of doxycycline post-exposure prophylaxis (DoxyPEP) — a single 200 mg dose after sex shown to reduce syphilis and chlamydia by up to 70%.
• Increased antibiotic use for respiratory illnesses, which may unintentionally suppress bacterial STIs (though this raises concerns about antibiotic resistance).
• Cross-protection from vaccines, especially the meningococcal B vaccine, which may offer indirect protection against gonorrhea.

Each of these factors could contribute to fewer detected infections — but they also complicate how we interpret national trends.

The Data Gaps That Distort the Picture

Dr. Varma cautions that surveillance data are only as good as their completeness.
The CDC’s new “One CDC Data Platform,” launched in 2022, has caused delays and inconsistencies in reporting from several states, and 2024 data lacked key demographic breakdowns — including by race, ethnicity, and gender identity.

Without those details, the true distribution of infections — and disparities across communities — may be hidden. The decline in reported infections could reflect under-testing rather than true progress. Many local health departments have cut staff or clinic hours, and without knowing how many people were actually tested, interpreting declines becomes guesswork.

Syphilis and the Warning Signs Within the Data

Dr. Varma notes that most of the drop in syphilis cases occurred among men, especially men who have sex with men (MSM) — a group more likely to access PrEP and DoxyPEP. Among women, however, early undiagnosed infections actually rose by nearly 8%, signaling ongoing transmission in heterosexual networks.

Most alarming: congenital syphilis — infections passed from mother to child — continued to climb. Despite overall declines in syphilis, congenital cases have risen nearly 700% since 2014. That indicates persistent failures in screening, prenatal care, and early treatment.

A Rear-View Mirror on Public Health

Dr. Varma describes surveillance data as a “rear-view mirror” of public health — showing us where we’ve been, not what’s happening right now. While declines among men may reflect the benefits of biomedical prevention, rising infections among women and infants highlight how uneven that progress is.

His closing takeaway is clear: data must guide action, not complacency. Even encouraging numbers can mask systemic failures when testing, equity, and prevention aren’t evenly distributed.

Learn More

You can read Dr. Varma’s full article, “Are STIs truly declining, or is our data just not very good? What the 2024 CDC STI report really shows,” on Healthbeat.org.

To explore more of Dr. Varma’s public-health writing, visit DrJayVarma.com.

FAQs

• How accurate are STI surveillance systems in the U.S.?
• What is DoxyPEP and how effective is it for STI prevention?
• Why is congenital syphilis still rising when adult cases decline?
• How do social and racial disparities affect STI trends?
• How can better testing and reporting improve public-health outcomes?