Molecular epidemiology of a hepatitis C virus epidemic in a haemodialysis unit: outbreak investigation and infection outcome

<p>Abstract</p> <p>Background</p> <p>HCV is a leading cause of liver chronic diseases all over the world. In developed countries the highest prevalence of infection is reported among intravenous drug users and haemodialysis (HD) patients. The present report is to identify the pathway of HCV transmission during an outbreak of HCV infection in a privately run haemodialysis (HD) unit in Italy in 2005.</p> <p>Methods</p> <p>Dynamics of the outbreak and infection clinical outcomes were defined through an ambi-directional cohort study. Molecular epidemiology techniques were used to define the relationships between the viral variants infecting the patients and confirm the outbreak. Risk analysis and auditing procedures were carried out to define the transmission pathway(s).</p> <p>Results</p> <p>Of the 50 patients treated in the HD unit 5 were already anti-HCV positive and 13 became positive during the study period (AR = 28.9%). Phylogenic analysis identified that, all the molecularly characterized incident cases (10 out of 13), were infected with the same viral variant of one of the prevalent cases. The multivariate analysis and the auditing procedure disclosed a single event of multi-dose vials heparin contamination as the cause of transmission of the infection in 11 out of the 13 incident cases; 2 additional incident cases occurred possibly as a result of inappropriate risk management.</p> <p>Discussion</p> <p>More than 30% of all HCV infections in developed countries results from poor application of standard precautions during percutaneous procedures. Comprehensive strategy which included: educational programmes, periodical auditing on standard precaution, use of single-dose vials whenever possible, prospective surveillance for blood-borne infections (including a system of prompt notification) and risk assessment/management dedicated staff are the cornerstone to contain and prevent outbreaks in HD</p> <p>Conclusions</p> <p>The outbreak described should serve as a reminder to HD providers that patients undergoing dialysis are at risk for HCV infection and that HCV may be easily transmitted whenever standard precautions are not strictly applied.</p

The role of hemodialysis machines dedication in reducing Hepatitis C transmission in the dialysis setting in Iran: A multicenter prospective interventional study

BACKGROUND: Hepatitis C virus (HCV) infection is a significant problem among patients undergoing maintenance hemodialysis (HD). We conducted a prospective multi-center study to evaluate the effect of dialysis machine separation on the spread of HCV infection. METHODS: Twelve randomly selected dialysis centers in Tehran, Iran were randomly divided into two groups; those using dedicated machines (D) for HCV infected individuals and those using non-dedicated HD machines (ND). 593 HD cases including 51 HCV positive (RT-PCR) cases and 542 HCV negative patients were enrolled in this study. The prevalence of HCV infection in the D group was 10.1% (range: 4.6%– 13.2%) and it was 7.1% (range: 4.2%–16.8%) in the ND group. During the study conduction 5 new HCV positive cases and 169 new HCV negative cases were added. In the D group, PCR positive patients were dialyzed on dedicated machines. In the ND group all patients shared the same machines. RESULTS: In the first follow-up period, the incidence of HCV infection was 1.6% and 4.7% in the D and ND group respectively (p = 0.05). In the second follow-up period, the incidence of HCV infection was 1.3% in the D group and 5.7% in the ND group (p < 0.05). CONCLUSIONS: In this study the incidence of HCV in HD patients decreased by the use of dedicated HD machines for HCV infected patients. Additional studies may help to clarify the role of machine dedication in conjunction with application of universal precautions in reducing HCV transmission

Epidemiological, clinical and therapeutic associations of hepatitis C types in western European patients.

Abstract BACKGROUND/AIMS: Different variants of hepatitis C virus might show different susceptibility to interferon alpha treatment, but it is important to understand whether this difference in sensitivity reflects an association with other factors, such as cirrhosis or age. METHODS: We have used an enzyme-linked immunosorbent hepatitis C virus typing assay based upon the detection of antibody in patient's era to type-specific NS-4 antigens to investigate the effect of hepatitis C virus type in 610 patients with chronic hepatitis C virus infection. The influence of viral types and their interdependency with host factors were separately analyzed to establish which factors executed an independent effect on the probability of sustained response. RESULTS: There was a marked difference in the distribution of hepatitis C virus types with age: infection with type 3 was more common in younger patients. The distribution of hepatitis C virus type with age is accounted for by differences in risk-factors for infection in different age groups. The frequency of cirrhosis increased markedly with age. Even after standardization for age, center and the presence of cirrhosis, viral type was strongly related to the outcome of infection. CONCLUSIONS: Our data suggest that enzyme-linked immunosorbent hepatitis C virus typing could assist in patient selection for interferon treatment to improve sustained response rates. Together with measurement of viral load, hepatitis C virus typing may serve to indicate the probability of response in patients with chronic hepatitis C, and to elucidate antiviral mechanisms in the disease. The serotyping assay provides a relatively inexpensive screening method to determine the infecting hepatitis C virus type, which could facilitate therapeutic decisions and strategies in patients with chronic hepatitis C