Patient-Care Practices Associated with an Increased Prevalence of Hepatitis C Virus Infection among Chronic Hemodialysis Patients

Objective. To identify patient-care practices related to an increased prevalence of hepatitis C virus (HCV) infection among chronic hemodialysis patients. Design. Survey. Setting. Chronic hemodialysis facilities in the United States. Participants. Equal-probability 2-stage cluster sampling was used to select 87 facilities from all Medicare-approved providers treating 30–150 patients; 53 facilities and 2,933 of 3,680 eligible patients agreed to participate. Methods. Patients were tested for HCV antibody and HCV RNA. Data on patient-care practices were collected using direct observation. Results. The overall prevalence of HCV infection was 9.9% (95% confidence interval [CI], 8.2%–11.6%); only 2 of 294 HCV-positive patients were detected solely by HCV RNA testing. After adjusting for non-dialysis-related HCV risk factors, patient-care practices independently associated with a higher prevalence of HCV infection included reusing priming receptacles without disinfection (odds ratio [OR], 2.3 [95% CI, 1.4–3.9]), handling blood specimens adjacent to medications and clean supplies (OR, 2.2 [95% CI, 1.3–3.6]), and using mobile carts to deliver injectable medications (OR, 1.7 [95% CI, 1.0–2.8]). Independently related facility covariates were at least 10% patient HCV infection prevalence (OR, 3.0 [95% CI, 1.8–5.2]), patient-to-staff ratio of at least 7: 1 (OR, 2.4 [95% CI, 1.4–4.1]), and treatment duration of at least 2 years (OR, 2.4 [95% CI, 1.3–4.4]). Conclusions. This study provides the first epidemiologic evidence of associations between specific patient-care practices and higher HCV infection prevalence among hemodialysis patients. Staff should review practices to ensure that hemodialysis-specific infection control practices are being implemented, especially handling clean and contaminated items in separate areas, reusing items only if disinfected, and prohibiting mobile medication and clean supply carts within treatment areas

Diagnosis of Hepatitis A Virus Infection: a Molecular Approach

Current serologic tests provide the foundation for diagnosis of hepatitis A and hepatitis A virus (HAV) infection. Recent advances in methods to identify and characterize nucleic acid markers of viral infections have provided the foundation for the field of molecular epidemiology and increased our knowledge of the molecular biology and epidemiology of HAV. Although HAV is primarily shed in feces, there is a strong viremic phase during infection which has allowed easy access to virus isolates and the use of molecular markers to determine their genetic relatedness. Molecular epidemiologic studies have provided new information on the types and extent of HAV infection and transmission in the United States. In addition, these new diagnostic methods have provided tools for the rapid detection of food-borne HAV transmission and identification of the potential source of the food contamination

Ongoing Transmission of Hepatitis B Virus Infection Among Inmates at a State Correctional Facility

Objectives. We sought to determine hepatitis B virus (HBV) infection prevalence, associated exposures, and incidence among male inmates at a state correctional facility. Methods. A cross-sectional serological survey was conducted in June 2000, and susceptible inmates were retested in June 2001. Results. At baseline, 230 inmates (20.5%; 95% confidence interval [CI]=18.2%, 22.9%) exhibited evidence of HBV infection, including 11 acute and 11 chronic infections. Inmates with HBV infection were more likely than susceptible inmates to have injected drugs (38.8% vs 18.0%; adjusted prevalence odds ratio [OR]=3.0; 95% CI=1.9, 4.9), to have had more than 25 female sex partners (27.7% vs 17.5%; adjusted prevalence OR=2.0; 95% CI=1.4, 3.0), and to have been incarcerated for more than 14 years (38.4% vs 17.6%; adjusted prevalence OR=1.7; 95% CI=1.1, 2.6). One year later, 18 (3.6%) showed evidence of new HBV infection. Among 19 individuals with infections, molecular analysis identified 2 clusters involving 10 inmates, each with a unique HBV sequence. Conclusions. We documented ongoing HBV transmission at a state correctional facility. Similar transmission may occur at other US correctional facilities and could be prevented by vaccination of inmates

Genetic relatedness of hepatitis A virus strains recovered from different geographical regions

A pairwise comparison of the nucleic acid sequence of 168 bases from 152 wild-type or unique cell culture-adapted strains of hepatitis A virus (HAV) revealed that HAV strains can be differentiated genetically into seven unique genotypes (I to VII). In general, the nucleotide sequence of viruses in different genotypes differs at 15 to 25% of positions within this segment of the genome. Viruses from four of the genotypes (I, II, III and VII) were recovered from cases of hepatitis A in humans, whereas viruses from the other three genotypes (IV, V and VI) were isolated only from simian species developing a hepatitis A-like illness during captivity. Among non-epidemiologically related human HAV strains, 81 were characterized as genotype I, and 19 as genotype III. Within each of these major genotypes, there were two distinct groups (subgenotypes), which differed in sequence at approximately 7.5% of base positions. Each genotype and subgenotype has a characteristic amino acid sequence in this region of the polyprotein, with the most divergent genotypes differing at 10 of 56 residues. Strains recovered from some geographical regions belonged to a common (endemic) genotype, whereas strains from other regions belonged to several, probably imported, genotypes. Thus, HAV strains recovered in North America were for the most part closely related at the nucleotide sequence level, whereas in other regions, such as Japan and Western Europe, HAV strains were derived from multiple genotypes or sub-genotypes. These data indicate that patterns of endemic transmission can be differentiated from situations in which infections are imported due to travel