Syphilis

Infections.

How common is Syphilis in the US?

Case rate of reported syphilis (all stages) in the United States: 62.5 per 100 000 (US population (cases per 100,000 persons); United States, 2023). Source: Clinical Chemistry, 2025. Label: REPORTED.

• 62.5 per 100 000 Case rate of reported syphilis (all stages) in the United States. Out of: US population (cases per 100,000 persons). Where: United States. When: 2023. Label: REPORTED.

  The current case rate of 62.5 per 100 000 persons represents a 30-fold increase since 2000-2001, when a concerted national effort nearly eliminated the disease.

  Source: Advances in Syphilis Diagnostics to Address the 21st-Century Epidemic Clinical Chemistry, 2025. PubMed 40510004. DOI 10.1093/clinchem/hvaf072.

Each figure measures something different. Do not compare them with each other or with other conditions.

Medical codes

• ICD-10-CM FY2026: A53.9 Syphilis, unspecified (narrower). Congenital and staged syphilis use other codes.

Research activity

As of 2026-09-24: 158 registered studies on ClinicalTrials.gov (search Syphilis) and 5,102 PubMed records, 2021 to 2025. A count of records is not how common or serious the condition is.

Population information, not medical advice. Methodology · Known limitations