Expanding PrEP Services for Men Who Have Sex With Men and Transgender Persons Through Health Department Programs: Key Processes and Outcomes From Project PrIDE, 2015-2019.

OBJECTIVE: Pre-exposure prophylaxis (PrEP) Implementation, Data to Care, and Evaluation (PrIDE) was a demonstration project implemented by 12 state and local health departments during 2015-2019 to expand PrEP services for men who have sex with men (MSM) and transgender persons at risk for HIV infection. We describe findings from the cross-jurisdictional evaluation of the project. METHODS: We analyzed work plans, annual progress reports, and aggregate quantitative program data submitted by funded health departments (n = 12) to identify key activities implemented and summarize key project outcomes. RESULTS: PrIDE jurisdictions implemented multiple health equity-focused activities to expand PrEP services to priority populations, including building program capacity, conducting knowledge and awareness campaigns, providing PrEP support services, and addressing barriers to PrEP use. Overall, PrIDE jurisdictions identified 44 813 persons with PrEP indications. Of these, 74.8% (n = 33 500) were referred and 33.1% (n = 14 821) were linked to PrEP providers, and 25.3% (n = 11 356) were prescribed PrEP. Most persons prescribed PrEP were MSM or transgender persons (87.9%) and persons from racial and ethnic minority groups (65.6%). However, among persons with PrEP indications, non-Hispanic Black/African American persons (14.9% of 18 782) were less likely than non-Hispanic White persons (31.0% of 11 633) to be prescribed PrEP (z = -33.57; P < .001). CONCLUSIONS: PrIDE jurisdictions successfully expanded PrEP services for MSM, transgender persons, and racial and ethnic minority groups by implementing health equity-focused activities that addressed barriers to PrEP services. However, PrEP prescription was generally low, with significant disparities by demographic characteristics. Additional targeted interventions are needed to expand PrEP services, achieve equity in PrEP use, and contribute to ending the HIV epidemic in the United States.

Expanding Data to Care Programs to Improve HIV Care Continuum Among Men Who Have Sex With Men and Transgender Persons: Key Processes and Outcomes From Project PrIDE, 2015-2019.

OBJECTIVES: During 2015-2019, five local and state health department jurisdictions implemented Data to Care (D2C) programs supported by Project PrIDE (Pre-exposure prophylaxis, Implementation, Data to Care, and Evaluation) to improve linkage or reengagement in HIV medical care among persons with HIV (PWH) who had gaps in care, particularly among men who have sex with men (MSM) and transgender persons. We describe findings from the cross-jurisdiction evaluation of the project. METHODS: We conducted a qualitative analysis of the final progress reports submitted by PrIDE jurisdictions to the Centers for Disease Control and Prevention to identify key D2C activities implemented and challenges encountered. We also conducted descriptive analysis on aggregate quantitative data to summarize key D2C program outcomes. RESULTS: PrIDE jurisdictions implemented multiple activities to build their D2C capacity, identify PWH who were not in care or virally suppressed, provide linkage/reengagement services, and monitor outcomes. Overall, 11 463 PWH were selected for follow-up, 45% of whom were MSM or transgender persons. Investigations were completed for 8935 (77.9%) PWH. Only 2323 (26.0%) PWH were confirmed not in care or virally suppressed; 1194 (51.4%) were subsequently linked/reengaged in care; among those, 679 (56.9%) were virally suppressed at last test. PrIDE jurisdictions identified data-related (eg, incomplete or delayed laboratory results), program capacity (eg, insufficient staff), and social and structural (eg, unstable housing) challenges that affected their D2C implementation. CONCLUSIONS: PrIDE jurisdictions successfully enhanced their D2C capacity, reached priority populations who were not in care or virally suppressed, and improved their engagement in care and health outcomes. Data-related and non-data-related challenges limited the efficiency of D2C programs. Findings can help inform other D2C programs and contribute to national HIV prevention goals.

Evolution of landscape pattern and the association with ecosystem services in the Ili-Balkhash Basin.

The Ili-Balkhash Basin in Central Asia is an arid endorheic basin shared by China and Kazakhstan. Population growth, socio-economic development, ecological conservation measures, and climate change have spurred land use and land cover changes and ecosystem services variations. This study used the long-term dataset from 1992 to 2018 to detect the landscape pattern evolution and its association with ecosystem services. The landscape pattern was quantified using landscape metrics, and the GeoDetector model quantified the driving factors of landscape pattern evolution. The ecosystem service value was assessed using the benefit transfer method. The time series trend was identified by the linear regression analysis combined with the Mann-Kendall algorithm, and Pearson's correlation coefficient was used to confirm the correlation. The temporal dynamics of the landscape pattern indicated the significant conversion of bare land to grassland. Cropland and urban land expanded significantly at the expense of forestland, grassland, and bare land. Various landscape elements tended to be more uniformly distributed across the basin with more regular shape and higher aggregation. The ecosystem service value increased significantly, and its correlation with the landscape pattern varied according to land use and land cover (LULC) types. The weakened shape complexity, the strengthened aggregation degree, and the more uniform distribution of different LULC types helped elevate total ecosystem service value. The results advanced the understanding of landscape pattern evolution and provided the scientific reference for land management regarding ecosystem services. Given the watershed ecosystem's integrity, transboundary cooperation between China and Kazakhstan was suggested to reinforce watershed sustainability through integrated watershed land resource planning and the joint adaptive strategies to climate change.

Evaluating for health equity among a cluster of health departments implementing PrEP services.

African American/Black and Hispanic/Latino sexual and gender minority populations are disproportionately affected by HIV in the United States and continue to experience HIV-related disparities. CDC funded project PrIDE to support 12 health departments (HD) with implementing pre-exposure prophylaxis (PrEP) strategies for men who have sex with men (MSM) and transgender persons, with a health-equity focus established by HDs. Each HD conducted mixed-methods evaluation of at least one local strategy. CDC employed a cluster evaluation approach to maximize cross validation. As a result, this cluster evaluation focused on three HDs that evaluated health equity-focused PrEP implementation strategies. Findings suggest that integrating health equity strategies such as storytelling and healthcare worker (HCW) trainings can help reduce HIV-related disparities. Storytelling improved HCW's understanding of clients' experiences of stigma due to racial, gender, and sexual identities. Provider training increased competencies on culturally appropriate care and the use of clinic services by Black and Hispanic MSM and transgender persons. Good practices included community engagement, seeking leadership buy-in, and integration of programmatic staff in health equity and evaluation activities. Evaluating strategies and training policies addressing social determinants of health that adversely affect HIV outcomes may help mitigate barriers Black and Hispanic MSM and transgender populations encounter in their HIV prevention seeking efforts.

Trends in Diagnosis of HIV Infection, Linkage to Medical Care, and Viral Suppression Among Men Who Have Sex with Men, by Race/Ethnicity and Age - 33 Jurisdictions, United States, 2014-2018.

During 2018, gay, bisexual, and other men who have sex with men (MSM) accounted for 69.4% of all diagnoses of human immunodeficiency virus (HIV) infection in the United States (1). Moreover, in all 42 jurisdictions with complete laboratory reporting of CD4 and viral load results,* percentages of MSM linked to care within 1 month (80.8%) and virally suppressed (viral load <200 copies of HIV RNA/mL or interpreted as undetected) within 6 months (68.3%) of diagnosis were below target during 2018 (2). African American/Black (Black), Hispanic/Latino (Hispanic), and younger MSM disproportionately experience HIV diagnosis, not being linked to care, and not being virally suppressed. To characterize trends in these outcomes, CDC analyzed National HIV Surveillance System† data from 2014 to 2018. The number of diagnoses of HIV infection among all MSM decreased 2.3% per year (95% confidence interval [CI] = 1.9-2.8). However, diagnoses did not significantly change among either Hispanic MSM or any MSM aged 13-19 years; increased 2.2% (95% CI = 1.0-3.4) and 2.0% (95% CI = 0.6-3.3) per year among Black and Hispanic MSM aged 25-34 years, respectively; and were highest in absolute count among Black MSM. Annual percentages of linkage to care within 1 month and viral suppression within 6 months of diagnosis among all MSM increased (2.9% [95% CI = 2.4-3.5] and 6.8% [95% CI = 6.2-7.4] per year, respectively). These findings, albeit promising, warrant intensified prevention efforts for Black, Hispanic, and younger MSM.

Improving the HIV Prevention Landscape to Reduce Disparities for Black MSM in the South.

Black men who have sex with men (MSM) in the South have the highest rates of HIV diagnosis in the country adding to the persistent racial disparities in HIV experienced by this population. The current HIV prevention and care landscape is heavily driven by individual-level clinical and biomedical approaches that have shown progress in reducing HIV diagnoses, but yield less than adequate results in reducing the HIV racial disparities for Black MSM in the South. In efforts to enhance focus on reducing the racial HIV disparities and more completely address the needs of Black MSM in the South, we offer insight on comprehensive approaches that can complement our current HIV prevention and care portfolio. There are five domains we discuss which include: (1) leveraging and integrating resources; (2) building upon existing program models designed to reduce disparities; (3) workforce development and cultural sensitivity; (4) social determinants of health data utilization; and 5) policy considerations. We urge public health practitioners and healthcare providers to consider and incorporate the outlined approaches to improve HIV outcomes along the continuum of care and ultimately reduce disparities in HIV affecting the quality of life of Black MSM living in the South.

Awareness of residents' technical ability can affect margin status in breast conserving operations.

PURPOSE: The current study was performed to determine if awareness of the potential affect of residents could affect margin status. METHODS: Retrospective review of all patients who underwent lumpectomy from July 2006 to May 2017 was evaluated. The effect of surgical residents' participation and their technical ability was evaluated to determine the effect on margin status. Logistic regression analysis was performed to determined factors which affect margin status. RESULTS: Of 444 patients, 14% of patients had positive margins. The positive margin rate was lower during the second time period after the effect of technical ability of the residents was known 12% versus 19% (p = 0.10). Greater participation by the attending surgeon (32% vs. 21%) occurred in the second time period. In multivariate logistic regression analysis, operations done by residents with satisfactory technical skills or attending surgeon were less likely to have positive margins than those done by residents with unsatisfactory technical skills (OR 0.19, 95% CI 0.10-0.38; p = 0.0001). With mean follow-up of 48 months, 1.4% had local recurrences as a first event. CONCLUSIONS: Technically ability of residents appears to affect margin status after lumpectomy. Increased intervention by the attending surgeon can improve this outcome.

Closed therapy of thoracic and lumbar vertebral body fractures in trauma patients.

BACKGROUND: The failure rate for the closed/non-surgical treatment of thoracic and lumbar vertebral body fractures (TLVBF) in trauma patients has not been adequately evaluated utilizing computed tomography (CT) studies. METHODS: From 2007 to 2008, consecutive trauma patients, who met inclusion criteria, with a CT diagnosis of acute TLVBF undergoing closed treatment were assessed. The failure rates for closed therapy, at 3 months post-trauma, were defined by progressive deformity, vertebral body collapse, or symptomatic/asymptomatic pseudarthrosis. The Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification was utilized to classify the fractures (groups A1 and non-A1 fractures) and were successively followed with CT studies. RESULTS: There were 54 patients with 91 fractures included in the study; 66 were A1 fractures, and 25 were non-A1 fractures. All had rigid bracing applied with flat and upright X-ray films performed to rule out instability. None had sustained spinal cord injuries. Thirteen patients (24%) failed closed therapy [e.g. 13 failed fractures (14%) out of 91 total fractures]. Five failed radiographically only (asymptomatic), and eight failed radiographically and clinically (symptomatic). A1 fractures had a 4.5% failure rate, while non-A1 fractures failed at a rate of 40%. CONCLUSION: Failure of closed therapy for TLVBF in the trauma population is not insignificant. Non-A1 fractures had a much higher failure rate when compared to A1 fractures. We recommend close follow-up particularly of non-A1 fractures treated in closed fashion using successive CT studies.

Flexible mate choice may contribute to ecotype assortative mating in pumpkinseed sunfish (Lepomis gibbosus).

Gene flow is expected to limit adaptive divergence, but the ecological and behavioural factors that govern gene flow are still poorly understood, particularly at the earliest stages of population divergence. Reduced gene flow through mate choice (sexual isolation) can evolve even under conditions of subtle population divergence if intermediate phenotypes have reduced fitness. We indirectly tested the hypothesis that mate choice has evolved between coexisting littoral and pelagic ecotypes of polyphenic pumpkinseed sunfish (Lepomis gibbosus) that have diverged in morphology and resource use and where intermediate phenotypes have reduced performance. We assessed the ecotype of nesting males and females using stable isotope estimates of diet and a divergent male morphological trait, oral jaw width. We found positive assortative mating between ecotypes in a common spawning habitat along exposed lake shorelines, but contrary to expectations, assortative mating was variably expressed between two sampling years. Although the factors that influence variable assortative mating remain unclear, our results are consistent with mate choice being expressed by ecotypes. Despite being variably expressed, mate choice will reduce gene flow between ecotypes and could contribute to further adaptive divergence depending on its frequency and strength in the population. Our findings add to a growing body of evidence indicating mate choice behaviour can be a plastic trait, an idea that should be more explicitly considered in empirical studies of mate choice as well as conceptual frameworks of mate choice evolution and adaptive divergence.

Goal directed enoxaparin dosing provides superior chemoprophylaxis against deep vein thrombosis.

INTRODUCTION: Optimal enoxaparin dosing for deep venous thrombosis (DVT) prophylaxis remains elusive. Prior research demonstrated that trauma patients at increased risk for DVT based upon Greenfield's risk assessment profile (RAP) have DVT rates of 10.8% despite prophylaxis. The aim of this study was to determine if goal directed prophylactic enoxaparin dosing to achieve anti-Xa levels of 0.3-0.5IU/ml would decrease DVT rates without increased complications. MATERIALS AND METHODS: Retrospective review of trauma patients having received prophylactic enoxaparin and appropriately timed anti-Xa levels was performed. Dosage was adjusted to maintain an anti-Xa level of 0.3-0.5IU/ml. RAP was determined on each patient. A score of ≥5 was considered high risk for DVT. Sub-analysis was performed on patients who received duplex examinations subsequent to initiation of enoxaparin therapy to determine the incidence of DVT. RESULTS: 306 patients met inclusion criteria. Goal anti-Xa levels were met initially in only 46% of patients despite dosing of >40mg twice daily in 81% of patients; however, with titration, goal anti-Xa levels were achieved in an additional 109 patients (36%). An average enoxaparin dosage of 0.55mg/kg twice daily was required for adequacy. Bleeding complications were identified in five patients (1.6%) with three requiring intervention. There were no documented episodes of HIT. Subsequent duplex data was available in 197 patients with 90% having a RAP score >5. Overall, five DVTs (2.5%) were identified and all occurred in the high-risk group. All patients were asymptomatic at the time of diagnosis. CONCLUSION: An increased anti-Xa range of 0.3-0.5IU/ml was attainable but frequently required titration of enoxaparin dosage. This produced a lower rate of DVT than previously published without increased complications.

Computed tomographic imaging interpretation improves fetal outcomes after maternal trauma.

BACKGROUND: Computed tomography (CT) has been validated to identify and classify placental abruption following blunt trauma. The purpose of this study was to demonstrate improvement in fetal survival when delivery occurs by protocol at the first sign of class III fetal heart rate tracing in pregnant trauma patients with a viable fetus on arrival and CT evidence of placental perfusion 50% or less secondary to placental abruption. METHODS: This is a retrospective review of pregnant trauma patients at 26 weeks' gestation or greater who underwent abdominopelvic CT as part of their initial evaluation. Charts were reviewed for CT interpretation of placental pathology with classification of placental abruption based upon enhancement (Grade 1, >50% perfusion; Grade 2, 25%-50% perfusion; Grade 3, <25% perfusion), as well as need for delivery and fetal outcomes. RESULTS: Forty-one patients met inclusion criteria. Computed tomography revealed evidence of placental abruption in six patients (15%): Grade 1, one patient, Grade 2, one patient, and Grade 3, four patients. Gestational ages ranged from 26 to 39 weeks. All patients with placental abruption of Grade 2 or greater developed concerning fetal heart tracings and underwent delivery emergently at first sign. Abruption was confirmed intraoperatively in all cases. Each birth was viable, and Apgar scores at 10 minutes were greater than 7 in 80% of infants, all of whom were ultimately discharged home. The remaining infant was transferred to an outside facility. CONCLUSIONS: Delivery at first sign of nonreassuring fetal heart rate tracings in pregnant trauma patients (third trimester) with placental abruption of Grade 2 or greater can lead to improved fetal outcome. LEVEL OF EVIDENCE: Therapeutic/care management study, level III.

Provider barriers prevent recommended sexually transmitted disease screening of HIV-infected men who have sex with men.

BACKGROUND: HIV-infected men who have sex with men (MSM) are at increased risk for transmitting and acquiring sexually transmitted diseases (STDs). Guidelines recommend at least annual screening of HIV-infected MSM for syphilis and for chlamydia and gonorrhea at exposed anatomical sites, to protect their health and their sexual partners' health. Despite these guidelines, STD screening has been suboptimal, with very low nongenital chlamydia and gonorrhea testing rates. Our objective was to better understand barriers encountered by HIV care providers in adhering to STD screening guidelines for HIV-infected MSM. METHODS: We conducted 40 individual semistructured interviews with health care providers (physicians, midlevel providers, nurses, and health educators) of HIV-infected MSM at 8 large HIV clinics in 6 US cities. Providers were asked about their STD screening practices and barriers to conducting sexual risk assessments of their patients. Emerging themes were identified by qualitative data analysis. RESULTS: Although most health care providers reported routine syphilis screening, screening for chlamydia and gonorrhea at exposed anatomical sites was less frequent. Obstacles that prevented routine chlamydia and gonorrhea screening included time constraints, difficulty obtaining a sexual history, language and cultural barriers, and patient confidentiality concerns. CONCLUSIONS: Providers reported many obstacles to routine chlamydia and gonorrhea screening. Interventions are needed to help to mitigate barriers to STD screening, such as structural and patient-directed health services models that might facilitate increased testing coverage of these important preventive services.

Invisible and at risk: STDs among young adult sexual minority women in the United States.

CONTEXT: Sexual minority women are not adequately assessed by national STD surveillance systems, and research regarding STD burden in nationally representative samples of such women is rare. Moreover, few studies have assessed STD risk exclusively among young adult women. METHODS: Wave 4 (2007-2008) data from the National Longitudinal Study of Adolescent Health on 7,296 females aged 24-32 were used to examine the relationship between sexual orientation and receipt of an STD diagnosis in the past year. Multivariate logistic regression analyses used two measures of sexual orientation: sexual identity and gender of sex partners. RESULTS: Eighty percent of women considered themselves straight; 16% mostly straight; and 4% bisexual, mostly gay or gay. Eighty-five percent had had only male partners, while 7% had had one female partner, and 8% two or more female partners. In unadjusted models, women who identified themselves as mostly straight were more likely than straight women to have had an STD (odds ratio, 1.4); mostly gay or gay women were at lower risk (0.4). Women who had had two or more female partners had a higher STD risk than did women who had had only male partners (1.7). Adjusting for social and demographic characteristics did not substantially alter these results; however, the associations between sexual identity, gender of sex partners and STD diagnosis were eliminated after adjustment for sexual behaviors (e.g., having had anal sex). CONCLUSIONS: Sexual identity, gender of sex partners and sexual behaviors should be taken into account in assessments of women's STD risk.

Water scarcity: moving beyond indexes to innovative institutions.

Water scarcity is a media darling often times described as a trigger of conflict in arid regions, a by-product of human influences ranging from desertification to climate change, or a combination of natural- and human-induced changes in the water cycle. A multitude of indexes have been developed over the past 20 years to define water scarcity to map the "problem" and guide international donor investment. Few indexes include groundwater within the metrics of "scarcity." Institutional communication contributes to the recognition of local or regional water scarcity. However, evaluations that neglect groundwater resources may incorrectly define conditions as scarce. In cases where there is a perception of scarcity, the incorporation of groundwater and related storage in aquifers, political willpower, new policy tools, and niche diplomacy often results in a revised status, either reducing or even eliminating the moniker locally. Imaginative conceptualization and innovative uses of aquifers are increasingly used to overcome water scarcity.

The association of sexual orientation measures with young adults' health-related outcomes.

OBJECTIVES: We examined associations among 3 dimensions of sexual orientation (identity, behavior, and attraction) and key health-related indicators commonly studied among sexual minority populations: depressive symptoms, perceived stress, smoking, binge drinking, and victimization. METHODS: We analyzed data from the National Longitudinal Study of Adolescent Health, Wave IV (2007-2008) when respondents were aged 24 to 32 years (n=14,412). We used multivariate linear and logistic regressions to examine consistency of associations between sexual orientation measures and health-related indicators. RESULTS: Strength of associations differed by gender and sexual orientation measure. Among women, being attracted to both sexes, identifying as "mostly straight" or "bisexual," and having mostly opposite-sex sexual partners was associated with greater risk for all indicators. Among men, sexual attraction was unrelated to health indicators. Men who were "mostly straight" were at greater risk for some, but not all, indicators. Men who had sexual partners of the same-sex or both sexes were at lower risk for binge drinking. CONCLUSIONS: Using all 3 dimensions of sexual orientation provides a more complete picture of the association between sexual orientation and health among young adults than does using any 1 dimension alone.

Socioeconomic impact on device-associated infections in limited-resource neonatal intensive care units: findings of the INICC.

PURPOSE: To evaluate the impact of country socioeconomic status and hospital type on device-associated healthcare-associated infections (DA-HAIs) in neonatal intensive care units (NICUs). METHODS: Data were collected on DA-HAIs from September 2003 to February 2010 on 13,251 patients in 30 NICUs in 15 countries. DA-HAIs were defined using criteria formulated by the Centers for Disease Control and Prevention. Country socioeconomic status was defined using World Bank criteria. RESULTS: Central-line-associated bloodstream infection (CLA-BSI) rates in NICU patients were significantly lower in private than academic hospitals (10.8 vs. 14.3 CLA-BSI per 1,000 catheter-days; p < 0.03), but not different in public and academic hospitals (14.6 vs. 14.3 CLA-BSI per 1,000 catheter-days; p = 0.86). NICU patient CLA-BSI rates were significantly higher in low-income countries than in lower-middle-income countries or upper-middle-income countries [37.0 vs. 11.9 (p < 0.02) vs. 17.6 (p < 0.05) CLA-BSIs per 1,000 catheter-days, respectively]. Ventilator-associated-pneumonia (VAP) rates in NICU patients were significantly higher in academic hospitals than in private or public hospitals [13.2 vs. 2.4 (p < 0.001) vs. 4.9 (p < 0.001) VAPs per 1,000 ventilator days, respectively]. Lower-middle-income countries had significantly higher VAP rates than low-income countries (11.8 vs. 3.8 per 1,000 ventilator-days; p < 0.001), but VAP rates were not different in low-income countries and upper-middle-income countries (3.8 vs. 6.7 per 1,000 ventilator-days; p = 0.57). When examined by hospital type, overall crude mortality for NICU patients without DA-HAIs was significantly higher in academic and public hospitals than in private hospitals (5.8 vs. 12.5%; p < 0.001). In contrast, NICU patient mortality among those with DA-HAIs was not different regardless of hospital type or country socioeconomic level. CONCLUSIONS: Hospital type and country socioeconomic level influence DA-HAI rates and overall mortality in developing countries.

Healthcare-associated infections: think globally, act locally.

Healthcare-associated infections (HAIs) have been a hot topic for several decades. An understanding of HAIs should be based on an understanding of the organisms that cause infection and determine prevention. Although some improvements in control in hospitals have been recorded, the community setting is now implicated, and the role of microbiology in diagnosis, detection of carriers and strain typing of organisms is evident. As healthcare systems vary widely, prevention strategies must be designed accordingly. Hand hygiene, however, remains applicable in all settings, and the WHO is strongly promoting alcohol-based hand rubs to interrupt transmission. Some countries are only beginning to develop standards, whereas compliance is obligatory in others. Economics and cost factors are common to all countries, and litigation is increasingly a factor in some.

Implicit ambivalence from attitude change: an exploration of the PAST model.

Traditional models of attitude change have assumed that when people appear to have changed their attitudes in response to new information, their old attitudes disappear and no longer have any impact. The present research suggests that when attitudes change, the old attitude can remain in memory and influence subsequent behavior. Four experiments are reported in which initial attitudes were created and then changed (or not) with new information. In each study, the authors demonstrate that when people undergo attitude change, their old and new attitudes can interact to produce evaluative responses consistent with a state of implicit ambivalence. In Study 1, individuals whose attitudes changed were more neutral on a measure of automatic evaluation. In Study 2, attitude change led people to show less confidence on an implicit but not an explicit measure. In Studies 3 and 4, people whose attitudes changed engaged in greater processing of attitude-relevant information than did individuals whose attitudes were not changed.

TST reversion in a BCG-revaccinated population of nursing and medical students, São Paulo, Brazil, 1997-2000.

SETTING: A major university in São Paulo, Brazil, where vaccination against tuberculosis (TB) with bacille Calmette-Guerin (BCG) was routinely offered to first-year medical and nursing students. OBJECTIVES: To estimate the probability of negative tuberculin skin test (TST) results over a 4-year period following BCG revaccination, and to evaluate the effect of factors associated with reversion. DESIGN: Students were enrolled in 1997, initially given a two-step TST, and were retested annually or biannually for the duration of the study. Data on TB exposures and potential risk factors for TST negativity and reversion were collected through annual surveys. A linear mixture survival model was used to estimate the probability of negative TST results over time. RESULTS: Of 159 students, an estimated 20% had a negative TST result despite revaccination, and a further 31% reverted to negative over 4 years of follow-up. No cofactors significantly affected the probability of reversion. CONCLUSION: Overall, in the absence of reported exposure to Mycobacterium tuberculosis, 51% of students revaccinated upon entering nursing or medical school would have a negative TST result by the time they begin their internships. In this recently vaccinated population, reversion was common, suggesting that annual TST screening may remain a useful tool.