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Syphilis epidemic

Syphilis epidemic

In 2021, there were 11 cases of congenital syphilis (parent to child transmission) in King County, a more than 10-fold increase compared to 2020 when only 1 case of congenital syphilis was identified. Congenital syphilis is a devastating disease that can lead to miscarriage, stillbirth, neonatal death, prematurity, and long-term health outcomes in infants affected. Congenital syphilis is a consequence of rising rates of syphilis among heterosexual cis-men and -women. Syphilis cases among gay, bisexual, and other men who have sex with men are also very high and rising. Currently, reported syphilis cases are low (less than 1%) among transgender and non-binary people.

In response, Public Health — Seattle & King County has created a Syphilis task force which includes a monthly review of real time syphilis data to guide public health interventions. The data presented on this page report on the monthly syphilis case counts by population in Seattle and King County. These data are not final and are subject change. Only the annual STD Epidemiology Report should be used for the most accurate reporting.


2024 Syphilis testing guidelines for cisgender women (including pregnant individuals) and
cisgender men who have sex with women*

Sexually active individuals aged 45 and under who have not been tested since January 2021 should get tested for syphilis.

Sexually active individuals should test annually and whenever they get medical care (up to every 3 months) if they: (1) use injection drugs (2) use methamphetamine or nonprescription opioids (3) are houseless or unstably housed (4) have transactional sex (5) entered a correctional facility or have been  incarcerated in the last 2 years (6) had syphilis or gonorrhea in the last 2 years (7) are living with HIV and are sexually active outside of a mutually monogamous relationship (8) are a woman whose male partners have sex with both men and women (9) have a sex partner with any of the above risk factors for syphilis.
Pregnant individuals should be tested during their: (1) first prenatal care visit (2) 3rd-trimester [laboratory testing done during the 24th-28th week of pregnancy] (3) time of delivery.
Pregnant individuals who have not had prenatal care, or their prenatal care status is unknown, should be tested any time they are in a clinical setting (i.e., emergency department, jail, substance use treatment facilities, OB triage, labor and delivery, etc.)

Pregnant individuals should also be tested if their fetus has died after 20 weeks.

*Syphilis testing guidelines for other populations can be found in the 2024 Syphilis Screening Guidelines (PDF)


Link/share our site at kingcounty.gov/syphilis

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