Demographics, Socio-Behavioral Factors, and Drug Use Patterns: What Matters in Spontaneous HCV Clearance?

Hepatitis C virus (HCV), an emerging bloodborne pathogen, causes chronic liver disease frequently except in about 10-20% of infections which undergo spontaneous resolution. Investigating factors that influence viral clearance is essential to understand the natural history of this infection and establishing novel strategies for prevention and treatment. HCV clearance was estimated in a unique cohort of 1,260 HIV and HBV negative current drug users enrolled for a hepatitis B vaccination study. It was defined as the inability to detect viral RNA using a PCR method in presence of serum anti-HCV antibody EIA. Associated demographic and socio-behavioral factors including drug use patterns were identified from the enrolled subjects using multivariate regression analysis. 33.3% (420/1260) of drug users were found positive for anti-HCV antibodies and 14.8% (62/420) of these individuals achieved viral clearance (negative PCR test). Race or ethnicity of the participants was the only significant factor associated with HCV clearance. Hispanics (OR ¼ 3.4, 95% CI: 1.3-8.5, P ¼ 0.01) and Caucasians (OR ¼ 3.1, 95% CI: 1.5-6.6, P ¼ 0.003) had significantly higher odds of clearing the virus compared to African Americans when adjusted for age and gender. None of the socio-behavioral factors including alcohol intake and drug use patterns were significant determinants of HCV clearance. Racial or ethnic differences in HCV clearance were observed in this study suggesting an important role of host genetic susceptibility factors in determining the clinical course of this disease. Further research is needed to examine these genetic associations of host-virus relationships

Invasive Mold Infections Following Hurricane Harvey-Houston, Texas

BACKGROUND: Characterizing invasive mold infection (IMI) epidemiology in the context of large flooding events is important for public health planning and clinical decision making. METHODS: We assessed IMI incidence (per 10 000 healthcare encounters) 1 year before and after Hurricane Harvey at 4 hospitals in Houston, Texas. Potential IMI cases were assigned as proven or probable cases using established definitions, and surveillance cases using a novel definition. We used rate ratios to describe IMI incidence and multivariable logistic regression to examine patient characteristics associated with IMI case status. RESULTS: IMI incidence was significantly higher posthurricane (3.69 cases) than prehurricane (2.50 cases) (rate ratio, 1.48 [95% confidence interval, 1.10-2.00]), largely driven by surveillance IMI cases. CONCLUSIONS: IMI incidence likely increased following Hurricane Harvey and outcomes for IMI patients were severe. Patient and clinician education on IMI prevention and identification is warranted, particularly as the frequency of extreme weather events increases due to climate change

Epidemiologic Characterization of Culture Positive Mycobacterium tuberculosis Patients by katG-gyrA Principal Genetic Grouping

Molecular typing techniques make it possible to genetically characterize Mycobacterium tuberculosis isolates. Public health strategies to control the spread of tuberculosis are enhanced by the use of molecular data to study tuberculosis transmission dynamics within populations. This study compared epidemiological and clinical characteristics of three M. tuberculosis groups based on polymorphisms at katG codon 463 and gyrA codon 95 in 1893 culture-positive patients by a retrospective nested case-comparison design. Study participants, diagnosed from 1995 to 2001 in the Houston, Texas metropolitan area, were ≥ 18 years old, 70% male, 66% U.S.-born, 40% Black, 29% Hispanic, 19% White, and 12% Asian/Pacific Islander. The prevalence of each principal genetic group (GG) was 30% (GG1), 52% (GG2), and 18% (GG3). Multiple logistic regression analysis showed that GG1 participants were more likely to be Asian, male, and have a history of homelessness, as compared with participants with either GG2 or GG3 isolates. GG2 participants were more likely to be Hispanic, have streptomycin-resistant isolates, and be infected with HIV than either GG1 or GG3 participants. GG3 participants were more likely to be Black or Hispanic, report illicit drug use, and live in a congregative facility at the time of diagnosis, than GG1 or GG2 participants. Ethnicity and sociodemographic findings were significant, prompting additional research into social networks, genetic susceptibility, immunology, and virulence factors

A new class of highly potent, broadly neutralizing antibodies isolated from viremic patients infected with dengue virus

Dengue is a rapidly emerging, mosquito-borne viral infection, with an estimated 400 million infections occurring annually. To gain insight into dengue immunity, we characterized 145 human monoclonal antibodies (mAbs) and identified a previously unknown epitope, the envelope dimer epitope (EDE), that bridges two envelope protein subunits that make up the 90 repeating dimers on the mature virion. The mAbs to EDE were broadly reactive across the dengue serocomplex and fully neutralized virus produced in either insect cells or primary human cells, with 50% neutralization in the low picomolar range. Our results provide a path to a subunit vaccine against dengue virus and have implications for the design and monitoring of future vaccine trials in which the induction of antibody to the EDE should be prioritized