Barbara S. Taylor

The Challenge of HIV-1 Subtype Diversity

HIV-1 has evolved multiple mechanisms to elude immune control. The view of virus as classifiable into distinct subtypes needs to reflect the reality of the constant emergence of new strains. This review discusses the implications of subtype diversity in HIV-1 for possible differential rates of disease progression, responses to antiretroviral therapy (including the development of resistance), and vaccine development.

Staphylococcus aureus ST398, New York City and Dominican Republic

Closely related Staphylococcus aureus strains of ST398, an animal-associated strain, were identified in samples collected from humans in northern Manhattan, New York, NY, USA, and in the Dominican Republic. A large population in northern Manhattan has close ties to the Dominican Republic, suggesting international transmission.

How complexity science can inform scale-up and spread in health care: understanding the role of self-organization in variation across local contexts.

Health care systems struggle to scale-up and spread effective practices across diverse settings. Failures in scale-up and spread (SUS) are often attributed to a lack of consideration for variation in local contexts among different health care delivery settings. We argue that SUS occurs within complex systems and that self-organization plays an important role in the success, or failure, of SUS. Self-organization is a process whereby local interactions give rise to patterns of organizing. These patterns may be stable or unstable, and they evolve over time. Self-organization is a major contributor to local variations across health care delivery settings. Thus, better understanding of self-organization in the context of SUS is needed. We re-examine two cases of successful SUS: 1) the application of a mobile phone short message service intervention to improve adherence to medications during HIV treatment scale up in resource-limited settings, and 2) MRSA prevention in hospital inpatient settings in the United States. Based on insights from these cases, we discuss the role of interdependencies and sensemaking in leveraging self-organization in SUS initiatives. We argue that self-organization, while not completely controllable, can be influenced, and that improving interdependencies and sensemaking among SUS stakeholders is a strategy for facilitating self-organization processes that increase the probability of spreading effective practices across diverse settings.

Molecular characterization of Staphylococcus aureus from outpatients in the Caribbean reveals the presence of pandemic clones

Staphylococcus aureus infections continue to pose a global public health problem. Frequently, this epidemic is driven by the successful spread of single S. aureus clones within a geographic region, but international travel has been recognized as a potential risk factor for S. aureus infections. To study the molecular epidemiology of S. aureus infections in the Caribbean, a major international tourist destination, we collected methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates from community-onset infections in the Dominican Republic (n = 112) and Martinique (n = 143). Isolates were characterized by a combination of pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing (MLST) typing. In Martinique, MRSA infections (n = 56) were mainly caused by t304-ST8 strains (n = 44), whereas MSSA isolates were derived from genetically diverse backgrounds. Among MRSA strains (n = 22) from the Dominican Republic, ST5, ST30, and ST72 predominated, while ST30 t665-PVL+ (30/90) accounted for a substantial number of MSSA infections. Despite epidemiological differences in sample collections from both countries, a considerable number of MSSA infections (~10%) were caused by ST5 and ST398 isolates at each site. Further phylogenetic analysis suggests the presence of lineages shared by the two countries, followed by recent genetic diversification unique to each site. Our findings also imply the frequent import and exchange of international S. aureus strains in the Caribbean.

Patterns of geographic mobility predict barriers to engagement in HIV care and antiretroviral treatment adherence.

Migration and geographic mobility increase risk for HIV infection and may influence engagement in HIV care and adherence to antiretroviral therapy. Our goal is to use the migration-linked communities of Santo Domingo, Dominican Republic, and New York City, New York, to determine the impact of geographic mobility on HIV care engagement and adherence to treatment. In-depth interviews were conducted with HIV+Dominicans receiving antiretroviral therapy, reporting travel or migration in the past 6 months and key informants (n=45). Mobility maps, visual representations of individual migration histories, including lifetime residence(s) and all trips over the past 2 years, were generated for all HIV+ Dominicans. Data from interviews and field observation were iteratively reviewed for themes. Mobility mapping revealed five distinct mobility patterns: travel for care, work-related travel, transnational travel (nuclear family at both sites), frequent long-stay travel, and vacation. Mobility patterns, including distance, duration, and complexity, varied by motivation for travel. There were two dominant barriers to care. First, a fear of HIV-related stigma at the destination led to delays seeking care and poor adherence. Second, longer trips led to treatment interruptions due to limited medication supply (30-day maximum dictated by programs or insurers). There was a notable discordance between what patients and providers perceived as mobility-induced barriers to care and the most common barriers found in the analysis. Interventions to improve HIV care for mobile populations should consider motivation for travel and address structural barriers to engagement in care and adherence.

High Risk of Obesity and Weight Gain for HIV-Infected Uninsured Minorities

Background:Obesity and HIV disproportionately affect minorities and have significant health risks, but few studies have examined disparities in weight change in HIV-seropositive (HIV+) cohorts. Objective:To determine racial and health insurance disparities in significant weight gain in a predominately Hispanic HIV+ cohort. Methods:Our observational cohort study of 1214 nonunderweight HIV+ adults from 2007 to 2010 had significant weight gain [≥3% annual body mass index (BMI) increase] as the primary outcome. The secondary outcome was continuous BMI over time. A 4-level race–ethnicity/insurance predictor reflected the interaction between race–ethnicity and insurance: insured white (non-Hispanic), uninsured white, insured minority (Hispanic or black), or uninsured minority. Logistic and mixed-effects models adjusted for baseline BMI, age, gender, household income, HIV transmission category, antiretroviral therapy type, CD4+ count, plasma HIV-1 RNA, observation months, and visit frequency. Results:The cohort was 63% Hispanic and 14% black; 13.3% were insured white, 10.0% uninsured white, 40.9% insured minority, and 35.7% uninsured minority. At baseline, 37.5% were overweight, 22.1% obese. Median observation was 3.25 years. Twenty-four percent of the cohort had significant weight gain, which was more likely for uninsured minority patients than insured whites [adjusted odds ratio = 2.85, 95% confidence intervals (CIs): 1.66 to 4.90]. The rate of BMI increase in mixed-effects models was greatest for uninsured minorities. Of 455 overweight at baseline, 29% were projected to become obese in 4 years. Conclusions and Relevance:In this majority Hispanic HIV+ cohort, 60% were overweight or obese at baseline, and uninsured minority patients gained weight more rapidly. These data should prompt greater attention by HIV providers for prevention of obesity.

High priority for hepatitis C screening in safety net hospitals: Results from a prospective cohort of 4582 hospitalized baby boomers

Low‐income populations are disproportionately affected by hepatitis C virus (HCV) infection. Thus, implementing baby boomer screening (born 1945‐1965) for HCV may be a high priority for safety net hospitals. We report the prevalence and predictors of HCV infection and advanced fibrosis or cirrhosis based on the Fibrosis‐4 score plus imaging for a baby boomer cohort admitted to a safety net hospital over a 21‐month interval with >9 months of follow‐up. Anti‐HCV antibody testing was performed for 4582, or 90%, of all never‐screened patients, of whom 312 (6.7%) tested positive. Adjusted odds ratios of testing anti‐HCV‐positive were 2.66 for men versus women (P < 0.001), 1.25 for uninsured versus insured (P = 0.06), 0.70 for Hispanics versus non‐Hispanic whites (P = 0.005), and 0.93 per year of age (P < 0.001). Among 287 patients tested for HCV RNA (91% of all anti‐HCV‐positive cases), 175 (61%) were viremic (3.8% overall prevalence in cohort), which was 5% less likely per year of age (P < 0.03). Noninvasive staging of 148 (84.6%) chronic HCV patients identified advanced fibrosis or cirrhosis in 50 (33.8%), with higher adjusted odds ratios of 3.21 for Hispanics versus non‐Hispanic whites/Asians (P = 0.02) and 1.18 per year of age (P = 0.001). Other factors associated with significantly higher adjusted odds ratios of advanced fibrosis or cirrhosis were alcohol abuse/dependence, obesity, and being uninsured. Conclusion: In this low‐income, hospitalized cohort, 4% of 4582 screened baby boomers were diagnosed with chronic HCV, nearly twice the rate in the community; one‐third had noninvasive testing that indicated advanced fibrosis or cirrhosis, which was significantly more likely for Hispanics, those of older age, those with obesity, those with alcohol abuse/dependence, and those who lacked insurance. (Hepatology 2015;62:1388–1395)

Implementing hospital-based baby boomer hepatitis c virus screening and linkage to care: Strategies, results, and costs

BACKGROUND/OBJECTIVE The US Preventive Services Task Force recommends 1-time hepatitis C virus (HCV) screening of all baby boomers (born 1945-1965). However, little is known about optimal ways to implement HCV screening, counseling, and linkage to care. We developed strategies following approaches used for HIV to implement baby boomer HCV screening in a hospital setting and report results as well as costs. DESIGN/PATIENTS Prospective cohort of 6140 baby boomers admitted to a safety-net hospital in South Texas from December 1, 2012 to January 31, 2014 and followed to December 10, 2014. PROCEDURES/MEASUREMENTS The HCV screening program included clinician/staff education, electronic medical record algorithm for eligibility and order entry, opt-out consent, anti-HCV antibody test with reflex HCV RNA, personalized inpatient counseling, and outpatient case management. Outcomes were anti-HCV antibody-positive and HCV RNA-positive results. RESULTS Of 3168 eligible patients, 240 (7.6%) were anti-HCV positive, which was more likely (P < 0.05) for younger age, men, and uninsured. Of 214 (89.2%) patients tested for HCV RNA, 134 (4.2% of all screened) were positive (chronic HCV). Among patients with chronic HCV, 129 (96.3%) were counseled, 108 (80.6%) received follow-up primary care, and 52 (38.8%) received hepatology care. Five patients initiated anti-HCV therapy. Total costs for start-up and implementation for 14 months were

High priority for hepatitis C screening in safety net hospitals

286,482. CONCLUSIONS This inpatient HCV screening program diagnosed chronic HCV infection in 4.2% of tested patients and linked >80% to follow-up care. Yet access to therapy is challenging for largely uninsured populations, and most programmatic costs of the program are not currently covered.

Results from two online surveys comparing sexual risk behaviors in Hispanic, black, and white men who have sex with men.

Low‐income populations are disproportionately affected by hepatitis C virus (HCV) infection. Thus, implementing baby boomer screening (born 1945‐1965) for HCV may be a high priority for safety net hospitals. We report the prevalence and predictors of HCV infection and advanced fibrosis or cirrhosis based on the Fibrosis‐4 score plus imaging for a baby boomer cohort admitted to a safety net hospital over a 21‐month interval with >9 months of follow‐up. Anti‐HCV antibody testing was performed for 4582, or 90%, of all never‐screened patients, of whom 312 (6.7%) tested positive. Adjusted odds ratios of testing anti‐HCV‐positive were 2.66 for men versus women (P < 0.001), 1.25 for uninsured versus insured (P = 0.06), 0.70 for Hispanics versus non‐Hispanic whites (P = 0.005), and 0.93 per year of age (P < 0.001). Among 287 patients tested for HCV RNA (91% of all anti‐HCV‐positive cases), 175 (61%) were viremic (3.8% overall prevalence in cohort), which was 5% less likely per year of age (P < 0.03). Noninvasive staging of 148 (84.6%) chronic HCV patients identified advanced fibrosis or cirrhosis in 50 (33.8%), with higher adjusted odds ratios of 3.21 for Hispanics versus non‐Hispanic whites/Asians (P = 0.02) and 1.18 per year of age (P = 0.001). Other factors associated with significantly higher adjusted odds ratios of advanced fibrosis or cirrhosis were alcohol abuse/dependence, obesity, and being uninsured. Conclusion: In this low‐income, hospitalized cohort, 4% of 4582 screened baby boomers were diagnosed with chronic HCV, nearly twice the rate in the community; one‐third had noninvasive testing that indicated advanced fibrosis or cirrhosis, which was significantly more likely for Hispanics, those of older age, those with obesity, those with alcohol abuse/dependence, and those who lacked insurance. (Hepatology 2015;62:1388–1395)