Increase in Incidence of Congenital Syphilis — United States, 2012–2014

Virginia Bowen, PhD; John Su, MD, PhD; Elizabeth Torrone, PhD; Sarah Kidd, MD; Hillard Weinstock, MD


Morbidity and Mortality Weekly Report. 2015;64(44):1241-1245. 

In This Article

Clinical Characteristics

The proportion of CS cases resulting in stillbirth and early infant death increased slightly during 2008–2014 (Table 2) from 24 (5.4%) stillbirths in 2008 to 25 (5.5%) in 2014, and from three (0.7%) infant deaths within 30 days of delivery in 2008 to eight (1.7%) in 2014. No vital status was recorded for five infants with CS (1.1%) in 2014.

Among 428 CS patients born alive in 2014, 28 (6.5%) had one or more clinical sign or symptom of CS infection (Table 3). The most commonly reported signs were syphilitic rash (n = 8), jaundice (n = 8), and hepatosplenomegaly (n = 5). An additional 49 (11.4%) had other evidence of CS infection, including long bone x-ray findings consistent with CS, a reactive cerebrospinal fluid (CSF) venereal disease research laboratory test, or an elevated CSF white blood cell count or protein level in the absence of another etiology. Forty-two infants (9.8%) did not have treatment recorded at the time the case was reported to CDC.§

Among 458 mothers of infants with CS in 2014, 100 (21.8%) received no prenatal care, and no information about prenatal care was available for 44 mothers (9.6%) (Table 3). Among the 314 mothers with one or more prenatal visit, 135 (43.0%) received no treatment for syphilis during the course of their pregnancy and 94 (30.0%) received inadequate treatment. The 135 mothers who received no treatment include 21 mothers who were never tested for syphilis during pregnancy and 52 mothers who tested negative for syphilis in early pregnancy and subsequently acquired syphilis before delivery. The remaining 62 mothers tested positive, but were not treated. Benzathine penicillin G is the only known effective treatment for preventing CS.[3] Maternal treatment was considered inadequate if it was initiated too late (<30 days before delivery), if a nonpenicillin therapy was administered, or if the dose of penicillin administered was inadequate for the mother's stage of syphilis.

§Newborn treatment for congenital syphilis might include either a 10-day course of aqueous crystalline or procaine penicillin G or one intramuscular dose of benzathine penicillin G, depending upon various factors related to 1) identification of syphilis in the mother; 2) adequacy of maternal treatment; 3) presence of clinical, laboratory, or radiographic evidence of syphilis in the neonate; and 4) comparison of maternal (at delivery) and neonatal serologic titers. Full guidance is available at