Household Transmission of Mpox to Children and Adolescents, California, 2022.

BACKGROUND: In California, the 2022 mpox outbreak cumulated 5572 cases, 20% of US cases, as of November 28, 2022; 0.3% of cases were among children <16 years old. The secondary attack rate (SAR) for children sharing households with infected adults is unknown. METHODS: A line list of pediatric mpox household contacts aged <16 years reported through August 31, 2022 was created. It included demographic and clinical information on the contacts. Pediatric contact lists were crossmatched with the state vaccination database to identify those who received postexposure prophylaxis (PEP) with the JYNNEOS vaccine. RESULTS: We identified 129 pediatric household contacts with median age of 7 years (range, 0-15 years). Among 18 symptomatic contacts, 12 (66.7%) underwent mpox testing; 5 (41.2%) were confirmed cases, 6 (50%) were negative, and 1 (0.8%) had an indeterminate result. Six symptomatic children were not tested for mpox (33.3%). Overall, 6 infected contacts were identified, resulting in a SAR of 4.7% (6 of 129). The majority of pediatric household contacts and 4 of 6 infected children identified as Hispanic/Latino. Only 18 children (14%) reported receiving PEP. CONCLUSIONS: The SAR was overall low among pediatric household contacts; none had severe disease. This may be underestimated given low testing rates.

COVID-19, HIV, and Syphilis Contact Tracing: What Have We Learned and Where Are We Headed?

ABSTRACT: Contact tracing is a core public health intervention for a range of communicable diseases, in which the primary goal is to interrupt disease transmission and decrease morbidity. In this article, we present lessons learned from COVID-19, HIV, and syphilis in San Francisco to illustrate factors that shape the effectiveness of contact tracing programs and to highlight the value of investing in a robust disease intervention workforce with capacity to pivot rapidly in response to a range of emerging disease trends and outbreak response needs.

Effectiveness of Syphilis Partner Notification After Adjusting for Treatment Dates, 7 Jurisdictions.

BACKGROUND: Disease intervention specialists (DIS) prevent syphilis by ensuring 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 the 2015-2017 period in 7 jurisdictions. We compared infected partners brought to treatment using the following: (1) DIS-assigned disposition codes or (2) all infected partners treated 0 to 90 days after the patient's interview (adjusted treatment estimate). Stratified analyses assessed patient characteristics associated with the adjusted treatment estimate. RESULTS: Disease intervention specialists interviewed 23,613 patients who reported 20,890 partners with locating information. Many of the 3569 (17.1%) partners classified by DIS as brought to treatment were treated before the patient was interviewed. There were 2359 (11.3%) partners treated 0 to 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 with DIS-assigned disposition (range, 6.1%-28.3%). Treatment for ≥1 partner occurred after 9.0% of interviews and was more likely if the patient was a woman (17.9%), younger than 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 to 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.

Contact-Tracing Outcomes Among Household Contacts of Fully Vaccinated Coronavirus Disease 2019 (COVID-19) Patients: San Francisco, California, 29 January-2 July 2021.

BACKGROUND: The extent to which vaccinated persons diagnosed with coronavirus disease 2019 (COVID-19) can transmit to other vaccinated and unvaccinated persons is unclear. METHODS: Using data from the San Francisco Department of Public Health, this report describes outcomes of household contact tracing during 29 January-2 July 2021, where fully vaccinated patients with COVID-19 were the index case in the household. RESULTS: Among 248 fully vaccinated patients with breakthrough infections, 203 (82%) were symptomatic and 105 were identified as the index patient within their household. Among 179 named household contacts, 71 (40%) contacts tested, over half (56%) were fully vaccinated and the secondary attack rate was 28%. Overall transmission from a symptomatic fully vaccinated patient with breakthrough infection to household contacts was suspected in 14 of 105 (13%) of households. Viral genomic sequencing of samples from 44% of fully vaccinated patients showed that 82% of those sequenced were infected by a variant of concern or interest and 77% by a variant carrying mutation(s) associated with resistance to neutralizing antibodies. CONCLUSIONS: Transmission from fully vaccinated symptomatic index patients to vaccinated and unvaccinated household contacts can occur. Indoor face masking and timely testing of all household contacts should be considered when a household member receives a positive test result in order to identify and interrupt transmission chains.

Unnamed Partners From Syphilis Partner Services Interviews, 7 Jurisdictions.

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 in 2015 to 2017 in 7 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 95,362-138,745) 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 (75%) compared with men who reported sex with women only (65%) and women (44%). CONCLUSIONS: Approximately 80% of sex partners were either unnamed or unreported. Partner services may be less successful at interrupting transmission in networks for men who reported sex with men where a higher proportion of partners are unnamed or unreported.

Historical and Current Trends in the Epidemiology of Early Syphilis in San Francisco, 1955 to 2016.

BACKGROUND: Seventeen years into a sustained epidemic, early syphilis (ES) rates in San Francisco (SF) are continuing to increase and the demographics of the affected population are changing. We provide a historical overview of ES in SF among men who have sex with men (MSM) and describe trends in the epidemiology and disease investigation outcomes. METHODS: We examined data from the SF Department of Public Health's patient-based registry of integrated STD surveillance, clinical, and field investigation data to describe demographic and behavioral characteristics of ES cases, as well as outcomes of syphilis partner services (PS). χ Tests were performed to examine categorical differences across periods. Analysis of variance was used to examine differences in continuous variables. RESULTS: In 2016, 1095 ES cases were reported among males in SF, a 219% increase from the 343 cases identified 10 years ago. Between 1996-1999 and 2010-2016, an increasing proportion of ES cases were among MSM younger than 25 years, nonwhite, and HIV negative (P < 0.05). A decreasing proportion of ES cases were assigned for PS, among whom a smaller proportion of reported sex partners were identified by name, resulting in an overall decline in the proportion of cases who had at least one named partner treated as a result of PS (Disease Intervention Rate) from 30.5 in 2000-2004 to 14.8 in 2010-2016. CONCLUSIONS: Syphilis case rates continue to increase in SF and the epidemic is expanding beyond a core population. Additional resources and innovative prevention approaches are needed to reduce the burden of syphilis among MSM.

Characteristics Associated With Delivery of an Infant With Congenital Syphilis and Missed Opportunities for Prevention-California, 2012 to 2014.

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 χ 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.

Impact of social network characteristics on shelter use among street youth in San Francisco.

PURPOSE: We examined the cross-sectional and longitudinal association between social network characteristics and street youths' shelter use, a determinant of health outcomes for homeless youth. METHODS: We analyzed interview data from 138 street youth recruited through venue-based sampling in San Francisco, to assess the cross-sectional relationship between shelter use in youths' social networks and youths' reported shelter use. We also assessed the relationship between baseline network shelter use and shelter use at 6-month follow-up. RESULTS: Low proportions of street youth reported shelter use at baseline (38%) and follow-up (29.6%). Twenty-nine (26.9%) youth were in networks with shelter users at baseline, compared with 17 youth (15.7%) at follow-up. In cross-sectional analysis, youth in networks with shelter users had 5-fold increased odds of reporting shelter use (OR: 5.86, p = .006). A 1-person increase in the number of network shelter users was associated with 2-fold increased odds of youths' shelter use (OR: 2.16, p = .02). In longitudinal analysis, youth in networks with shelter users at baseline had nearly 5-fold increased odds of shelter use at follow-up (OR: 4.95, p = .01). A 1-person increase in the number of network shelter users at baseline was associated with 3-fold increased odds of shelter use at follow-up (OR: 3.15, p = .004). CONCLUSION: Shelter users seem to cluster together. Shelter use by extended network members was associated with increased odds of youths' own shelter use. Understanding how network behaviors influence street youths' health-related behaviors, such as shelter use, could inform network-based interventions encouraging service uptake among marginalized and hard-to-reach street youth populations.

Syphilis outbreak at a California men's prison, 2007-2008: propagation by lapses in clinical management, case management, and public health surveillance.

This field report describes an investigation to identify cases to control a syphilis outbreak in a prison and determine whether clinical, case management, and surveillance practices influenced the outbreak occurrence, detection, or management. Key performance measures were assessed to evaluate timeliness and quality of clinical and case management activities and surveillance practices. Thirty cases were found. Prior to the investigation, median times for clinical and reporting/surveillance measures were 15 days from primary and secondary (P&S) symptom onset to exam, 7 days from P&S exam to treatment, and 63 days from serologic test to the state's receipt of case. After the investigation, these measures improved to 8, 4.5, and 28 days, respectively. Lack of adherence to surveillance and clinical management protocols likely contributed to this outbreak, which was curtailed by aggressive control measures.

Sex, drugs (methamphetamines), and the Internet: increasing syphilis among men who have sex with men in California, 2004-2008.

OBJECTIVES: We examined primary and secondary syphilis cases among men who have sex with men (MSM) in California, and the association of methamphetamine use and Internet use to meet sex partners (Internet use) with number of sex partners. METHODS: We analyzed California surveillance data for MSM who were diagnosed with syphilis between 2004 and 2008, to assess differences in the mean number of sex partners by methamphetamine use and mutually exclusive groups of patients reporting Internet use (Internet users). RESULTS: Large proportions of patients reported methamphetamine use (19.2%) and Internet use (36.4%). From 2006 through 2008, Adam4Adam was the most frequently reported Web site statewide, despite temporal and regional differences in Web site usage. Methamphetamine users reported more sex partners (mean = 11.7) than nonmethamphetamine users (mean = 5.6; P < .001). Internet users reported more sex partners (mean = 9.8) than non-Internet users (mean = 5.0; P < .001). Multivariable analysis of variance confirmed an independent association of methamphetamine and Internet use with increased numbers of sex partners. CONCLUSIONS: Higher numbers of partners among MSM syphilis patients were associated with methamphetamine and Internet use. Collaboration between currently stand-alone interventions targeting methamphetamine users and Internet users may offer potential advances in sexually transmitted disease control efforts.

Repeat syphilis among men who have sex with men in California, 2002-2006: implications for syphilis elimination efforts.

OBJECTIVES: We examined rates of and risk factors for repeat syphilis infection among men who have sex with men (MSM) in California. METHODS: We analyzed 2002 to 2006 California syphilis surveillance system data. RESULTS: During the study period, a mean of 5.9% (range: 4.9%-7.1% per year) of MSM had a repeat primary or secondary (PS) syphilis infection within 2 years of an initial infection. There was no significant increase in the annual proportion of MSM with a repeat syphilis infection (P = .42). In a multivariable model, factors associated with repeat syphilis infection were HIV infection (odds ratio [OR] = 1.65; 95% confidence interval [CI] = 1.14, 2.37), Black race (OR = 1.84; 95% CI = 1.12, 3.04), and 10 or more recent sex partners (OR = 1.99; 95% CI = 1.12, 3.50). CONCLUSIONS: Approximately 6% of MSM in California have a repeat PS syphilis infection within 2 years of an initial infection. HIV infection, Black race, and having multiple sex partners are associated with increased odds of repeat infection. Syphilis elimination efforts should include messages about the risk for repeat infection and the importance of follow-up testing. Public health attention to individuals repeatedly infected with syphilis may help reduce local disease burdens.