INTRODUCTION: Disease intervention specialists (DIS) prevent syphilis by assuring treatment for patients' sex partners through partner notification (PN). Different interpretations of how to measure partners treated due to DIS efforts complicates PN evaluation. We measured PN impact by counting partners treated for syphilis after DIS interviewed the patient. METHODS: We reviewed data from early syphilis cases reported during 2015-2017 in seven jurisdictions. We compared infected partners brought to treatment using: 1) DIS-assigned disposition codes or 2) all infected partners treated 0-90 days after the patient's interview (adjusted treatment estimate). Stratified analyses assessed patient characteristics associated with the adjusted treatment estimate. RESULTS: DIS interviewed 23,613 patients who reported 20,890 partners with locating information. Many of the 3,569 (17.1%) partners classified by DIS as brought to treatment were treated before the patient was interviewed. There were 2,359 (11.3%) partners treated 0-90 days after the patient's interview. Treatment estimates were more consistent between programs when measured using our adjusted estimates (range 6.1%-14.8% per patient interviewed) compared to DIS-assigned disposition (range 6.1%-28.3%). Treatment of >1 partner occurred after 9.0% of interviews and was more likely if the patient was a woman (17.9%), aged <25 years (12.6%), interviewed ≤7 days from diagnosis (13.9%), HIV negative (12.6%), or had no reported history of syphilis (9.8%). CONCLUSIONS: Counting infected partners treated 0-90 days after interview reduced variability in reporting and facilitates quality assurance. Identifying programs and DIS who are particularly good at finding and treating partners could improve program impact.

BACKGROUND: Reducing transmission depends on the percentage of infected partners treated; if many are missed, impact on transmission will be low. Traditional partner services metrics evaluate the number of partners found and treated. We estimated the proportion of partners of syphilis patients not locatable for intervention. METHODS: We reviewed records of early syphilis cases (primary, secondary, early latent) reported during 2015-2017 in seven jurisdictions (Florida, Louisiana, Michigan, North Carolina, Virginia, New York City, and San Francisco). Among interviewed syphilis patients, we determined the proportion who reported named partners (with locating information), reported unnamed partners (no locating information), and did not report partners. For patients with no reported partners, we estimated their range of unreported partners to be between one and the average number of partners for patients who reported partners. RESULTS: Among 29,719 syphilis patients, 23,613 (80%) were interviewed and 18,581 (63%) reported 84,224 sex partners (average=4.5; 20,853 (25%) named and 63,371 (75%) unnamed). An estimated 11,138 to 54,521 partners were unreported. Thus, 74,509 to 117,892 (of 95,362 to 138,745) partners were not reached by partner services (78-85%). Among interviewed patients, 71% reported ≥1 unnamed partner or reported no partners; this proportion was higher for men who reported sex with men [MSM] (75%), compared to men who reported sex with women only (65%), and women (44%). CONCLUSION: Approximately 80% of sex partners were either unnamed or unreported. Partner services may be less successful at interrupting transmission in MSM networks where a higher proportion of partners are unnamed or unreported.

BACKGROUND: Congenital syphilis (CS), the transmission of Treponema pallidum from mother to fetus during pregnancy, can cause adverse birth outcomes. In 2012 to 2014, the CS rate in California increased more than 200% from 6.6 to 20.3 cases per 100,000 live births. Our objectives were to identify characteristics associated with delivering an infant with CS and missed opportunities for prevention among syphilis-infected pregnant women in California. METHODS: We linked California Department of Public Health syphilis surveillance records from women aged 15 to 45 years-diagnosed from March 13, 2012, to December 31, 2014-to birth records. We compared characteristics among mothers who delivered an infant with CS (CS mothers) with mothers who delivered an infant without CS (non-CS mothers) by using chi or Fisher exact tests. To visualize gaps in prevention among syphilis-infected pregnant women, we constructed a CS prevention cascade, a figure that shows steps to prevent CS. RESULTS: During the selected period, 2498 women were diagnosed as having syphilis, and 427 (17%) linked to birth records; 164 (38%) were defined as CS mothers and 263 (62%) as non-CS mothers. Mothers with CS were more likely than non-CS mothers to have their first prenatal care visit in the third trimester. High proportions of mothers in both groups reported high-risk sexual behaviors, methamphetamine use, or incarceration (13%-29%). The CS prevention cascade showed decrements of 5% to 11% in prenatal care receipt, testing, and treatment steps; only 62% of potential CS births were prevented. CONCLUSIONS: Multifaceted efforts are needed to address gaps in the CS prevention cascade and reduce CS cases in California.