Modelling the impact of vaccination and sexual behaviour adaptations on mpox cases in the USA during the 2022 outbreak.

BACKGROUND: The 2022 mpox outbreak has infected over 30 000 people in the USA, with cases declining since mid-August. Infections were commonly associated with sexual contact between men. Interventions to mitigate the outbreak included vaccination and a reduction in sexual partnerships. Understanding the contributions of these interventions to decreasing cases can inform future public health efforts. METHODS: We fit a dynamic network transmission model to mpox cases reported by Washington DC through 10 January 2023. This model incorporated both vaccine administration data and reported reductions in sexual partner acquisition by gay, bisexual or other men who have sex with men (MSM). The model output consisted of daily cases over time with or without vaccination and/or behavioural adaptation. RESULTS: We found that initial declines in cases were likely caused by behavioural adaptations. One year into the outbreak, vaccination and behavioural adaptation together prevented an estimated 84% (IQR 67% to 91%) of cases. Vaccination alone averted 79% (IQR 64% to 88%) of cases and behavioural adaptation alone averted 25% (IQR 10% to 42%) of cases. We further found that in the absence of vaccination, behavioural adaptation would have reduced the number of cases, but would have prolonged the outbreak. CONCLUSIONS: We found that initial declines in cases were likely caused by behavioural adaptation, but vaccination averted more cases overall and was key to hastening outbreak conclusion. Overall, this indicates that outreach to encourage individuals to protect themselves from infection was vital in the early stages of the mpox outbreak, but that combination with a robust vaccination programme hastened outbreak conclusion.

Changes in Partner-Seeking and Sexual Behavior Among US Adults During the First 2 Years of the COVID-19 Pandemic.

BACKGROUND: The COVID-19 pandemic may have influenced partner-seeking and sexual behaviors of adults. METHODS: We examined cross-sectional survey data collected at the end of the first year (n = 1161) and second year (n = 1233) of the COVID-19 pandemic by the National Opinion Research Center's nationally representative, probability-based AmeriSpeak panel. Data were analyzed to (1) quantify behavioral changes across pandemic years, (2) examine changes of in-person dating prevalence during year 2, and (3) assess risk perception for acquiring COVID-19 or HIV/STIs through new partnerships during year 2. Weighted percentages were calculated for responses; univariate relationships between demographic characteristics and outcomes were assessed. RESULTS: Prevalence of new partners for dating remained stable across pandemic years (year 1: n = 1157 [10%]; year 2: n = 1225 [12%]). The prevalence of in-person sex with new partners was also stable (year 1: n = 1157 [7%], year 2: n = 1225 [6%]), marking a decline from a prepandemic estimate (2015-2016: 16%). Partner-seeking experiences varied by age and sexual identity in both years, and by race/ethnicity during year 2. Reports of in-person dating fluctuated throughout year 2, without clear relationship to viral variants. Respondents who met new partners in person during year 2 generally reported greater concern and preparedness for reducing risks associated with HIV/STIs than COVID-19. CONCLUSIONS: The prevalence of US adults seeking new partners for dating or sex remained stable across pandemic years. During future public health emergencies, public health officials are encouraged to offer guidance for reducing disease risks in partnerships, while emphasizing sexual health and providing tailored messaging for persons more susceptible to infection.

Modifications to Sexual Behaviors Associated With Mpox (Monkeypox) Virus Transmission Among Persons Presenting for mpox Vaccination, Washington, DC, August-October, 2022.

BACKGROUND: Over 30,000 mpox cases were reported during the 2022 mpox outbreak with many cases occurring among gay, bisexual and other men who have sex with men (MSM). Decreases in U.S. mpox cases were likely accelerated by a combination of vaccination and modifications to sexual behaviors associated with mpox virus transmission. We assessed reports of sexual behavior change among participants receiving mpox vaccination in Washington, DC. METHODS: During August to October 2022, 711 adults aged ≥18 years receiving mpox vaccination at two public health clinics in Washington, DC completed a self-administered questionnaire that asked whether sexual behaviors changed since learning about mpox. We calculated the frequency and percentages of participants reporting an increase, decrease, or no change in 4 of these behaviors by demographic, clinical, and behavioral characteristics with 95% confidence intervals. RESULTS: Overall, between 46% and 61% of participants reported a decrease in sexual behaviors associated with mpox virus transmission, 39% to 54% reported no change in these behaviors, and <1% reported an increase. Approximately 61% reported decreases in one-time sexual encounters (95% confidence interval [CI], 56.8%-64.7%), 54.3% reduced numbers of sex partners (95% CI, 50.4%-58.0%), 53.4% decreased sex via a dating app or sex venue (95% CI, 49.7%-58.0%), and 45.6% reported less group sex (95% CI, 40.4%-50.9%). Reported decreases in these behaviors were higher for MSM than women; in non-Hispanic Black than non-Hispanic White participants; and in participants with human immunodeficiency virus than participants without human immunodeficiency virus. CONCLUSIONS: Most participants receiving mpox vaccination reported decreasing sexual behaviors associated with mpox virus transmission, including groups disproportionately affected by the outbreak.

Using infection prevalence, seroprevalence and case report data to estimate chlamydial infection incidence.

OBJECTIVES: To measure the effectiveness of chlamydia control strategies, we must estimate infection incidence over time. Available data, including survey-based infection prevalence and case reports, have limitations as proxies for infection incidence. We therefore developed a novel method for estimating chlamydial incidence. METHODS: We linked a susceptible infectious mathematical model to serodynamics data from the National Health and Nutritional Examination Survey, as well as to annual case reports. We created four iterations of this model, varying assumptions about how the method of infection clearance (via treatment seeking, routine screening or natural clearance) relates to long-term seropositivity. Using these models, we estimated annual infection incidence for women aged 18-24 and 25-37 years in 2014. To assess model plausibility, we also estimated natural clearance for the same groups. RESULTS: Of the four models we analysed, the model that best explained the empirical data was the one in which longer-lasting infections, natural clearance and symptomatic infections all increased the probability of long-term seroconversion. Using this model, we estimated 5910 (quartile (Q)1, 5330; Q3, 6500) incident infections per 100 000 women aged 18-24 years and 2790 (Q1, 2500; Q3, 3090) incident infections per 100 000 women aged 25-37 years in 2014. Furthermore, we estimated that natural clearance rates increased with age. CONCLUSIONS: Our method can be used to estimate the number of chlamydia infections each year, and thus whether infection incidence increases or decreases over time and after policy changes. Furthermore, our results suggest that clearance via medical intervention may lead to short-term or no seroconversion, and the duration of untreated chlamydial infection may vary with age, underlining the complexity of chlamydial infection dynamics.

Changes in Oral and Anal Sex With Opposite-Sex Partners Among Sexually Active Females and Males Aged 15 to 44 Years in the United States: National Survey of Family Growth, 2011-2019.

BACKGROUND: Oral and anal sex with opposite-sex partners is common and associated with sexually transmitted infection (STI) transmission. Trends in these behaviors over the last decade, during which bacterial STI diagnoses have reached historic highs while HIV diagnoses have decreased, are not well understood. We examined recent trends in oral and anal sex and associated condom use with opposite-sex partners among females and males. METHODS: We analyzed data from 16,926 female and 13,533 male respondents aged 15 to 44 years who reported sex with an opposite-sex partner in the past 12 months from the National Survey of Family Growth, 2011-2019. We used survey-weighted linear or logistic regression to evaluate linear temporal trends in oral and anal sex behaviors. RESULTS: From 2011-2013 to 2017-2019, reports of oral sex and number of oral sex partners in the past 12 months increased among females (85.4% in 2011-2013 to 89.4% in 2017-2019; odds ratio [OR], 1.05 [95% confidence interval {CI}, 1.02-1.09], and ß = 0.014 [95% CI, 0.005-0.023]; respectively) but not males (ranges, 87.9%-89.1%; 1.27-1.31). Condom use at last oral sex decreased among both females and males (6.3%-4.3%: OR, 0.93 [95% CI, 0.88-0.99]; 5.9%-4.4%: OR, 0.95 [95% CI, 0.91-1.00]). Anal sex (ranges, 21.0%-23.3% [females] and 23.3%-24.6% [males]), number of anal sex partners (females, 0.22-0.25; males, 0.26-0.30), and condom use at last anal sex (females, 15.3%-18.2%; males, 27.0%-28.7%) remained stable. CONCLUSIONS: The frequency of oral and anal sex with opposite-sex partners among U.S. 15- to 44-year-olds, paired with limited and-for oral sex-decreasing condom use, demonstrates the need to understand the role of these behaviors in increasing STI diagnosis rates and the potential role of extragenital screening and condoms in reducing STI transmission.

Changes in Sexual Behaviors with Opposite-Sex Partners and Sexually Transmitted Infection Outcomes Among Females and Males Ages 15-44 Years in the USA: National Survey of Family Growth, 2008-2019.

Rates of reported gonorrhea and chlamydial infections have increased substantially over the past decade in the USA and disparities persist across age and race/ethnicity. We aimed to understand potential changes in sexual behaviors, sexual network attributes, and sexually transmitted infection (STI) screening that may be contributing to these trends. We analyzed data from 29,423 female and 24,605 male respondents ages 15-44 years from the National Survey of Family Growth, 2008-2019. We used survey-weighted linear or logistic regression to evaluate linear temporal trends in sexual behaviors with opposite-sex partners, network attributes, and STI testing, treatment, and diagnosis. Significant declines were observed in condom use at last vaginal sex, mean number of vaginal sex acts, proportion of condom-protected sex acts in the past 4 weeks, and racial/ethnic homophily with current partners among males and females from 2008-2010 through 2017-2019. Among males, mean number of female partners in the past 12 months and concurrency also declined, while the percent reporting ever having sex with another male increased. Past-year testing for chlamydia and any STI increased among females. Research is needed to understand how these changes interact and potentially contribute to increasing reported gonorrhea and chlamydia diagnoses and identify avenues for future intervention.

Diverging trends in US male-female condom use by STI risk factors: a nationally representative study.

OBJECTIVE: Condom use behaviours are proximal to recent STI increases in the USA, yet it remains unclear whether the use of condoms has changed over time among unmarried, non-cohabiting young men who have sex with women (MSW) and how this variability is influenced by STI risk factors. METHODS: To examine condom use over time among MSW aged 15-29, we used three cross-sectional surveys from the 2002, 2006-2010 and 2011-2017 National Survey of Family Growth. We estimated weighted percentages, adjusted prevalence ratios (APRs) and 95% confidence intervals (CI) to assess changes in condom use, stratified by whether MSW reported any STI risk factors in the past 12 months (ie, perceived partner non-monogamy, male-to-male sex, sex in exchange for money or drugs, sex partner who injects illicit drugs, or an HIV-positive sex partner). RESULTS: We observed a divergence in trends in condom use at last sex between men aged 15 -29 with STI risk factors in the past 12 months and those without such history. We saw significant declines in condom use from 2002 to 2011-2017 among men with STI risk factors (APR=0.80, 95% CI 0.68 to 0.95), specifically among those aged 15-19 (APR=0.73, 95% CI 0.57 to 0.94) or non-Hispanic white (APR=0.71, 95% CI 0.54 to 0.93). In contrast, trends in condom use among men with no STI factors remained stable or increased. Across all time periods, the most prevalent STI risk factor reported was perception of a non-monogamous female partner (23.0%-26.9%). Post-hoc analyses examined whether condom use trends changed once this variable was removed from analyses, but no different patterns were observed. CONCLUSIONS: While STIs have been increasing, men aged 15-29 with STI risk factors reported a decline in condom use. Rising STI rates may be sensitive to behavioural shifts in condom use among young MSW with STI risk factors.

County-Level Chlamydia and Gonorrhea Rates by Social Vulnerability, United States, 2014-2018.

ABSTRACT: We examined mean chlamydia and gonorrhea case rates from 2014 to 2018 by categorizing US counties by social vulnerability. Overall, these rates were approximately 1.0 to 2.4 times higher in high vulnerability counties than low vulnerability counties. Percentage change in case rates from low to high social vulnerability counties varied by sex, geographic region, and urbanicity.

Sexual Risk Behaviors Among Persons Diagnosed With Primary and Secondary Syphilis Who Reported High-Risk Substance Use: Data From the National Notifiable Diseases Surveillance System, 2018.

BACKGROUND: Recent increases in high-risk substance use (HRSU; i.e., injection drug use, heroin, methamphetamine, crack/cocaine) have coincided with rising primary and secondary (P&S) syphilis rates. To further understand these trends, we examined sexual risk behaviors among women, men who have sex with women only (MSW), and men who have sex with men (MSM) who were diagnosed with P&S syphilis in 2018 and reported HRSU. METHODS: Data on HRSU and sexual risk behaviors among persons with P&S syphilis were drawn from syphilis case reports in 2018 from the National Notifiable Diseases Surveillance System. Persons with P&S syphilis were asked about sexual risk behaviors in the past 12 months including exchange sex for drugs/money, sex while intoxicated and/or high on drugs, sex with a person who injects drugs (PWID), sex with an anonymous partner, and number of sex partners. We describe percentages and adjusted prevalence ratios (aPRs) for women, MSW, and MSM reporting these behaviors by age, race/Hispanic ethnicity, type of drug used, and incarceration history (both in the past 12 months). RESULTS: Among 19,634 persons diagnosed with P&S syphilis in 2018 with information on HRSU, 29.3% of women, 22.7% of MSW, and 12.4% of MSM reported HRSU. Among those reporting HRSU, percentages reporting exchange sex ranged from 17% to 35% (highest for women), whereas reports of anonymous sex ranged from 44% to 71% (highest for MSM). In this population, sexual risk behaviors were more commonly reported among those with a recent incarceration history than those without such history. Among those reporting injection drug use or heroin use, percentages reporting sex with a PWID ranged from 51% to 77%. In adjusted models, HRSU was significantly associated with one or more sexual risk behaviors for women (aPR, 2.63 [95% confidence interval {CI}, 2.39-2.90]; MSW: aPR, 1.38 [95% CI, 1.31-1.46]; and MSM: aPR, 1.30 [95% CI, 1.26-1.34]). CONCLUSIONS: Collaborative partnerships across the US public health system could help address barriers to timely clinical care among persons diagnosed with P&S syphilis who report HRSU.

Changes in Sexual Behavior Over the COVID-19 Pandemic Among a Community-Based Cohort of Men Who Have Sex With Men in Columbus, Ohio.

BACKGROUND: The purpose was to assess COVID-19 beliefs and attitudes and examine COVID-19-related changes in sexual behavior of men who have sex with men during 3 time periods: April-July 2020 (T1), August-December 2020 (T2), January-May 2021 (T3). METHODS: Data were analyzed from 157 men who have sex with men in Ohio recruited to participate in a longitudinal multisite network study of syphilis epidemiology in 3 US cities: Columbus, Ohio; Baltimore, Maryland; and Chicago, Illinois. In April 2020, a COVID-19 module was appended to existing baseline and follow-up surveys to assess beliefs, attitudes, and changes in sexual behavior. Sample characteristics were summarized. Correlations between demographic variables (age, racial identity) and COVID-19 outcomes were examined. RESULTS: In response to COVID-19 social distancing restrictions and self-reported anxiety, some men limited sexual activity at T1, but the majority (n = 105 [67%]) continued to engage in sex. The number of men engaging in sex increased over time (T2: n = 124 [79%]; T3: n = 121 [77%]). At T1, men not in a relationship more frequently reported having less sex compared with prepandemic (n = 39 [57%]). By T3, men in a relationship more frequently reported less sex (n = 32 [54%]). Increased anxiety about sex and condom use was positively correlated with identifying as a man of color (P < 0.001). Most of the sample reported either starting or increasing online sexual activity during each time period. CONCLUSIONS: Future efforts to target sexual health during a pandemic or other health emergencies should prioritize men of color and address the unique perspective of both single and partnered men.

Partner Seeking and Sexual Behavior in the United States During the COVID-19 Pandemic, March 2020 to March 2021.

ABSTRACT: We examined partner seeking and sexual behaviors among a representative sample of US adults (n = 1161) during the first year of the COVID-19 pandemic. Approximately 10% of survey respondents sought a new partner, with age and sexual identity being associated with partner seeking behavior. Approximately 7% of respondents had sex with a new partner, which marks a decrease as compared with a prepandemic estimate from 2015 to 2016 in which 16% of US adults reported having sex with a new partner during the past year. Among respondents who had in-person sex with a new partner during the first year of the pandemic, public health guidelines for in-person sexual activity were infrequently followed.

Factors Associated With Online Sex Partners Among Gay, Bisexual and Other Men Who Have Sex With Men: Results From a National Survey.

BACKGROUND: Associations between online sex seeking and increased risk for sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) among men who have sex with men (MSM) typically rely on convenience samples. We examined Internet and mobile app use for finding sex partners among a nationally representative sample of MSM. METHODS: We analyzed 2011 to 2017 data from the National Survey of Family Growth, a nationally representative sample of the civilian, non-institutionalized US population (15-44 years). The analytic sample was comprised of men who reported 1 or more same-sex partners in the past year. We also assessed associations between online sex-seeking and STI risk, sexual health care behaviors, and condom use. RESULTS: Of 13,320 male respondents, 442 (3.0%) reported sex with a man in the past year, of whom 215 (46.3%) had met a partner online. Between MSM who met partners online and those who did not, we found no differences by age, education, race/ethnicity or socioeconomic status. Men who have sex with men with online partners were more likely to identify as gay (68.4% vs 49.5%, P = 0.0124). They also reported more sex partners overall (M = 3.04 vs 1.60, P < 0.0001), and multiple insertive (46.3% vs 8.5%, P < 0.0001) and receptive (33.2% vs 15.4%, P = 0.0055) anal sex partners, in the past year. They were also more likely to receive sexual risk assessments (56.0% vs 40.4%, P = 0.0129), STI testing (57.4% vs 35.3%, P = 0.0002), and STI treatment (17.8% vs 8.7%, P = 0.0152) in the past year. We found no differences in condom use. CONCLUSIONS: Men who have sex with men who report using online sources to find sex partners are more likely than other MSM to report behaviors that increase risk for STI/HIV but are also more likely to engage in behaviors that may mitigate further transmission, such as STI testing.

Trends in factors indicating increased risk for STI among key subpopulations in the United States, 2002-2015.

OBJECTIVES: Within the context of rising rates of reportable STIs in the USA, we used national survey data to examine temporal trends in high-risk factors that indicate need for STI/HIV preventive services among key subpopulations with disproportionate STI rates. METHODS: We used data from the 2002 (n=12 571), 2006-2010 (n=22 682) and 2011-2015 (n=20 621) National Survey of Family Growth (NSFG). NSFG is a national probability survey of 15-44 year olds living in US households. We examined STI risk factors among sexually active men who have sex with men (MSM) and Hispanic, non-Hispanic black, 15-19 year old, 20-24 year old, and 25-29 year old women who have sex with men (WSM) and men who have sex with women (MSW). Risk behaviours included: received money or drugs for sex, gave money or drugs for sex, partner who injected drugs, partner who has HIV, non-monogamous partner (WSM, MSW only) and male partner who had sex with other men (WSM only). Endorsement of any of these behaviours was recoded into a composite variable focusing on factors indicating increased STI risk (yes/no). We used chi-squares and logistic regression (calculating predicted marginals to estimate adjusted prevalence ratios (aPRs)) to examine STI risk factors over time among the key subpopulations. RESULTS: From 2002 to 2011-2015, reported STI risk factors did not change or declined over time among key subpopulations in the USA. In adjusted analyses comparing 2002 to 2011-2015, we identified significant declines among WSM: Hispanics (aPR=0.84 (0.68-1.04), non-Hispanic blacks (aPR=0.69 (0.58-0.82), adolescents (aPR=0.71 (0.55-0.91) and 25-29 year olds (aPR=0.76 (0.58-0.98); among MSW: Hispanics (aPR=0.53 (0.40-0.70), non-Hispanic blacks (aPR=0.74 (0.59-0.94) and adolescents (aPR=0.63 (0.49-0.82); and among MSM (aPR=0.53 (0.34-0.84). CONCLUSIONS: While reported STIs have increased, STI risk factors among key subpopulations were stable or declined. Condom use related to these risk factors, sexual mixing patterns and STI testing should be examined.

Initial and Repeated Point Prevalence Surveys to Inform SARS-CoV-2 Infection Prevention in 26 Skilled Nursing Facilities - Detroit, Michigan, March-May 2020.

Skilled nursing facilities (SNFs) are focal points of the coronavirus disease 2019 (COVID-19) pandemic, and asymptomatic infections with SARS-CoV-2, the virus that causes COVID-19, among SNF residents and health care personnel have been described (1-3). Repeated point prevalence surveys (serial testing of all residents and health care personnel at a health care facility irrespective of symptoms) have been used to identify asymptomatic infections and have reduced SARS-CoV-2 transmission during SNF outbreaks (1,3). During March 2020, the Detroit Health Department and area hospitals detected a sharp increase in COVID-19 diagnoses, hospitalizations, and associated deaths among SNF residents. The Detroit Health Department collaborated with local government, academic, and health care system partners and a CDC field team to rapidly expand SARS-CoV-2 testing and implement infection prevention and control (IPC) activities in all Detroit-area SNFs. During March 7-May 8, among 2,773 residents of 26 Detroit SNFs, 1,207 laboratory-confirmed cases of COVID-19 were identified during three periods: before (March 7-April 7) and after two point prevalence surveys (April 8-25 and April 30-May 8): the overall attack rate was 44%. Within 21 days of receiving their first positive test results, 446 (37%) of 1,207 COVID-19 patients were hospitalized, and 287 (24%) died. Among facilities participating in both surveys (n = 12), the percentage of positive test results declined from 35% to 18%. Repeated point prevalence surveys in SNFs identified asymptomatic COVID-19 cases, informed cohorting and IPC practices aimed at reducing transmission, and guided prioritization of health department resources for facilities experiencing high levels of SARS-CoV-2 transmission. With the increased availability of SARS-CoV-2 testing, repeated point prevalence surveys and enhanced and expanded IPC support should be standard tools for interrupting and preventing COVID-19 outbreaks in SNFs.

Sexually Transmitted Infection Risk Reduction Strategies Among US Adolescents and Adults With Multiple Opposite-Sex Sex Partners or Perceived Partner Nonmonogamy, 2011-2017.

BACKGROUND: This study examined condom use and sexually transmitted infection (STI) testing among unmarried, non-cohabiting women and men who had multiple past-year partnerships or perceived their partner's involvement in another sexual relationship. METHODS: We identified 5868 and 5330 unmarried, non-cohabiting sexually active women and men aged 15 to 44 years using National Survey of Family Growth data for 2011 to 2017. To measure multiple partnerships, we created 4 dichotomous variables that included both past-year number of opposite-sex sex partners (1, 2 or more) and perceived partner nonmonogamy (PPNM) (yes, no). Results were stratified by relationship type at last sex ("steady" vs "casual"). RESULTS: Overall, 39.4% of women and 48.3% of men reported multiple partnerships and 23.4% and 24.0% reported PPNM. Lower condom use was seen for women and men who had 2 or more partners in the past year and PPNM than those with only 1 partner and no PPNM (women, 28.5%; 95% confidence interval [CI], 24.1-32.9 vs 39.3%; 95% CI, 36.6-41.9) (men, 37.7%; 33.5-41.8 vs 54.9%; 51.9-57.9). STI testing was higher for groups with PPNM. Men with a steady sex partner had higher prevalence of past-year STI testing if they reported PPNM than not (adjusted prevalence ratio, 2.00; 95% CI, 1.63-2.45). CONCLUSIONS: Screening practices that include a standardized sexual risk assessment could identify those with multiple sex partners or PPNM and improve linkage to STI services. Availability of point-of-care tests and expedited partner therapy could provide targeted strategies that prioritize rapid diagnosis and effective partner treatment which may prevent further STI spread.

Modeling the impact of changing sexual behaviors with opposite-sex partners and STI testing among women and men ages 15-44 on STI diagnosis rates in the United States 2012-2019.

Objective: To estimate the potential contributions of reported changes in frequency of penile-vaginal sex (PVS), condom use and STI screening to changes in gonorrhea and chlamydial diagnoses from 2012 to 2019. Methods: An agent-based model of the heterosexual population in the U.S. simulated the STI epidemics. Baseline was calibrated to 2012 diagnosis rates, testing, condom use, and frequency of PVS. Counterfactuals used behaviors from the 2017-2019 NSFG, and we evaluated changes in diagnosis and incidence rates in 2019. Results: Higher testing rates increased gonorrhea and chlamydia diagnosis by 14% and 13%, respectively, but did not reduce incidence. Declining frequency of PVS reduced the diagnosis rate for gonorrhea and chlamydia 6% and 3% respectively while reducing incidence by 10% and 9% respectively. Declining condom use had negligible impact on diagnosis and incidence. Conclusion: Understanding how changing behavior drives STI incidence is essential to addressing the growing epidemics. Changes in testing and frequency of PVS likely contributed to some, but not all, of the changes in diagnoses. More research is needed to understand the context within which changing sexual behavior and testing are occurring.

Role of the COVID-19 Pandemic on Sexual Behaviors and Receipt of Sexual and Reproductive Health Services Among U.S. High School Students - Youth Risk Behavior Survey, United States, 2019-2021.

Disproportionate rates of sexually transmitted diseases (STDs), including HIV, and unintended pregnancy among adolescents persist and might have been affected by the COVID-19 pandemic. This study uses 2019 and 2021 data from the nationally representative Youth Risk Behavior Surveys to characterize changes in sexual behaviors and receipt of sexual and reproductive health services among U.S. high school students before and during the pandemic. Outcomes included HIV testing (lifetime), STD testing (past 12 months), condom use (last sexual intercourse), and primary contraceptive method used to prevent pregnancy (last sexual intercourse). Except for HIV testing, all analyses were limited to currently sexually active students. Weighted prevalence and 95% CIs of outcomes for 2019 and 2021 were calculated for each year by demographics (sex [female or male], age, and race and ethnicity) and sex of sexual contacts (opposite sex only, both sexes, same sex only). For each year, pairwise t-tests with Taylor series linearization were used to identify demographic differences among outcomes. Across years, change in prevalence of outcomes was assessed by using absolute and relative measures of association overall and by demographics. During 2019-2021, the prevalence of HIV testing decreased by 3.68 percentage points, from 9.4% to 5.8%. Among sexually active students, prevalence of STD testing decreased by 5.07 percentage points, from 20.4% to 15.3%. Among sexually active students reporting opposite sex or both sexes sexual contact, intrauterine device or implant use at last sexual intercourse increased by 4.11 percentage points, from 4.8% to 8.9%, and no contraceptive method use increased by 2.74 percentage points, from 10.7% to 13.4%. Because of disruptions throughout the pandemic, results underscore the importance of improving access to a range of health services for adolescents and improving STD/HIV and unintended pregnancy prevention.

Factors Associated With Syphilis Transmission and Acquisition Among Men Who Have Sex With Men: Protocol for a Multisite Egocentric Network Study.

BACKGROUND: In the United States, the rates of primary and secondary syphilis have increased more rapidly among men who have sex with men (MSM) than among any other subpopulation. Rising syphilis rates among MSM reflect changes in both individual behaviors and the role of sexual networks (eg, persons linked directly or indirectly by sexual contact) in the spread of the infection. Decades of research examined how sexual networks influence sexually transmitted infections (STIs) among MSM; however, few longitudinal data sources focusing on syphilis have collected network characteristics. The Centers for Disease Control and Prevention, in collaboration with 3 sites, enrolled a prospective cohort of MSM in 3 US cities to longitudinally study sexual behaviors and STIs, including HIV, for up to 24 months. OBJECTIVE: The Network Epidemiology of Syphilis Transmission (NEST) study aimed to collect data on the factors related to syphilis transmission and acquisition among MSM. METHODS: The NEST study was a prospective cohort study that enrolled 748 MSM in Baltimore, Maryland; Chicago, Illinois; and Columbus, Ohio. NEST recruitment used a combination of convenience sampling, venue-based recruitment, and respondent-driven sampling approaches. At quarterly visits, participants completed a behavioral questionnaire and were tested for syphilis, HIV, gonorrhea, and chlamydia. The participants also provided a list of their sexual partners and described their 3 most recent partners in greater detail. RESULTS: The NEST participants were enrolled in the study from July 2018 to December 2021. At baseline, the mean age of the participants was 31.5 (SD 9.1) years. More than half (396/727. 54.5%) of the participants were non-Hispanic Black, 29.8% (217/727) were non-Hispanic White, and 8.8% (64/727) were Hispanic or Latino. Multiple recruitment strategies across the 3 study locations, including respondent-driven sampling, clinic referrals, flyers, and social media advertisements, strengthened NEST participation. Upon the completion of follow-up visits in March 2022, the mean number of visits per participant was 5.1 (SD 3.2; range 1-9) in Baltimore, 2.2 (SD 1.6; range 1-8) in Chicago, and 7.2 (SD 2.9; range 1-9) in Columbus. Using a community-based participatory research approach, site-specific staff were able to draw upon collaborations with local communities to address stigma concerning STIs, particularly syphilis, among potential NEST participants. Community-led efforts also provided a forum for staff to describe the NEST study objectives and plans for research dissemination to the target audience. Strategies to bolster data collection during the COVID-19 pandemic included telehealth visits (all sites) and adaptation to self-collection of STI specimens (Baltimore only). CONCLUSIONS: Data from NEST will be used to address important questions regarding individual and partnership-based sexual risk behaviors among MSM, with the goal of informing interventions to prevent syphilis in high-burden areas. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/40095.

Teenagers in the United States: sexual activity, contraceptive use, and childbearing, 2006-2010 national survey of family growth.

OBJECTIVE: This report presents national estimates of sexual activity, contraceptive use, and births among males and females aged 15-19 in the United States in 2006-2010 from the National Survey of Family Growth (NSFG). For selected indicators, data are also presented from the 1988, 1995, and 2002 NSFG, and from the 1988 and 1995 National Survey of Adolescent Males, conducted by the Urban Institute. METHODS: Descriptive tables of numbers and percentages are presented and discussed. Data were collected through in-person interviews of the household population of males and females aged 15-44 in the United States, between July 2006 and June 2010. Interviews were conducted with 22,682 men and women, including 4,662 teenagers (2,284 females and 2,378 males). For both the teen subsample and the total sample, the response rate was 77%. RESULTS: In 2006-2010, about 43% of never-married female teenagers (4.4 million), and about 42% of never-married male teenagers (4.5 million) had had sexual intercourse at least once. These levels of sexual experience have not changed significantly from 2002. Seventy-eight percent of females and 85% of males used a method of contraception at first sex according to 2006-2010 data, with the condom remaining the most popular method. Teenagers' contraceptive use has changed little since 2002, with a few exceptions: there was an increase among males in the use of condoms alone and in the use of a condom combined with a partner's hormonal contraceptive; and there was a significant increase in the percentage of female teenagers who used hormonal methods other than a birth-control pill, such as injectables and the contraceptive patch, at first sex. Six percent of female teenagers used a nonpill hormonal method at first sex.

Teenagers in the United States: sexual activity, contraceptive use, and childbearing, national survey of family growth 2006-2008.

OBJECTIVE: This report presents national estimates of sexual activity, contraceptive use, and births among males and females 15-19 years of age in the United States in 2006-2008 from the National Survey of Family Growth (NSFG). Selected data are also presented from the 1988, 1995, and 2002 NSFGs, and from the 1988 and 1995 National Survey of Adolescent Males (NSAM), conducted by the Urban Institute. METHODS: Descriptive tables of numbers and percents are presented and discussed. Data were collected through in-person interviews of the household population in the United States, conducted between July 2006 and December 2008. Interviews were conducted with 7,356 females-1,381 of whom were teenagers--and 6,140 males--1,386 of whom were teenagers-for a total of 2,767 teenagers. The overall response rate for the 2006-2008 NSFG was 75%. The response rate for female teenagers was 77% and for male teenagers 75%. RESULTS: In 2006-2008, about 42% of never-married female teenagers (4.3 million), and about 43% of never-married male teenagers (4.5 million) had had sexual intercourse at least once. These levels of sexual experience have not changed significantly from 2002, the last time the NSFG collected these data. Among never-married teenagers, 79% of females and 87% of males used a method of contraception at first sex. With a few exceptions, teenagers' use of contraceptives has changed little since 2002, and the condom remained the most commonly used method. One exception was an increase in the use of condoms and the use of a condom combined with a hormonal contraceptive (dual method use) among males. Another exception was a significant increase in the percent of female teenagers who had ever used periodic abstinence, or the "calendar rhythm" method. This method had been used by 17% of female teenagers in 2006-2008.