Sexually transmitted infections (STIs) in the United States dropped in 2024, marking a hopeful shift in public health trends.
According to tentative data from the U.S. Centers for Disease Control and Prevention (CDC), gonorrhea cases declined for the third straight year, while both adult chlamydia and the most contagious forms of syphilis fell for the second year in a row.
Doctors diagnosed about 1.5 million chlamydia cases, 543,000 gonorrhea cases, and more than 190,000 syphilis cases nationwide. Together, that added up to more than 2.2 million infections in 2024 — about 9% fewer than in 2023.
Congenital Syphilis Remains a Concern
Despite the good news for adults, congenital syphilis — an infection passed from mother to baby during pregnancy — continues to rise. Nearly 4,000 cases were reported in 2024, compared with only about 300 in 2012.
While the increase from 2023 was less than 2%, experts emphasize that congenital syphilis is entirely preventable.
Elizabeth Finley, interim executive director of the National Coalition of STD Directors, called the trend troubling:
“The continued rise in congenital syphilis is a distressing indication that we are not doing enough to protect pregnant women and newborns.”
Preventive Use of Antibiotics Shows Promise
The decline in adult syphilis cases may be linked to the growing use of doxycycline, an antibiotic some people take after sex to prevent infection.
The CDC noted that early-stage syphilis cases dropped by 22% in 2024, particularly among gay and bisexual men and transgender women who had recently been diagnosed with another STI.
Since syphilis is most contagious in its early stages, this reduction is seen as a significant public health achievement.
Gaps in Screening for Expectant Mothers
Still, prevention efforts have not yet reached all vulnerable groups. A recent CDC study found that only 80% of pregnant women in the United States are screened for syphilis. Experts stress that universal testing and treatment during pregnancy are essential to stopping congenital infections.
