Molecular epidemiology of an outbreak of HCV in a hemodialysis unit: Direct sequencing of HCV-HVR1 as an appropriate tool for phylogenetic analysis

Abstract

Infection with hepatitis C virus (HCV) is still a serious problem in hemodialysis patients, despite screening of blood products for anti-HCV antibodies. The prevalence of HCV in HD patients is between 15% and 30% in Germany. We report the molecular epidemiology of an HCV outbreak in a hemodialysis unit in 1997 is determined. HCV hypervariable region 1 (HVR1) was amplified from serum samples of 19 patients by polymerase chain reaction (PCR) and sequenced directly. In addition, HCV isolates from 3 of these 19 patients were cloned and sequenced. 14 newly infected patients and two patients, who had been infected for several years had very closely related HCV isolates. Unrelated HCV isolates as well as sequences obtained from an HCV outbreak in a plasmapheresis center were found in different, distantly related branches. These findings provide strong evidence for nosocomial transmission of the virus, despite following strict general hygiene precautions. The production of anti-HCV antibody was delayed significantly or seroconversion did not occur at all during the period of observation in 8 out of 14 newly infected HCV RNA positive patients. Close-meshed reverse transcription-polymerase chain reaction (RT-PCR) analyses on apparently non infected patients within hemodialysis units and upon admission of new patients is strongly recommended for the early detection and prevention of outbreaks of HCV.

Hepatitis C prevalence and risk factors in hemodialysis patients in Central Brazil: a survey by polymerase chain reaction and serological methods

“…The presence of HCV viremia in anti-HCVnegative hemodialysis patients has been frequently reported by others researchers (Bukh et al 1993, Masuko et al 1994, Seelig et al 1994, Pujol et al 1996, Schneeberger et al 1998). Just as in others studies (Caramelo et al 1996, Schroter et al 1997, Fabrizi et al 1999, Grethe et al 2000, we can not exclude recent infections, where the sample was collected during the seronegative window phase, or the existence of impaired immune responses in some of these patients. In addition, 8 of the unconfirmed serological results (1 LIA-negative and 7 LIA-indeterminates) were positive for HCV RNA.…”

“…These findings suggest a substantial risk in hemodialysis procedures. Moreover, nosocomial transmission among hemodialysis patients has been reently documented by molecular analysis (Sampietro et al 1995, Grethe et al 2000.…”

“…Such factors as blood transfusion, partial immunosuppression, and frequent parenteral interventions have been associated with an increased risk for infection . The duration of hemodialysis treatment, and the possibility of nosocomial HCV transmission have also been suggested as additional contributing elements (Masuko et al 1994, Sampietro et al 1995, Sandhu et al 1999, Scotto et al 1999, Grethe et al 2000. The prevalence of HCV antibodies (anti-HCV) has been reported to range from 2% in northwestern Europe to 76.3% in Indonesia (Soetjipto et al 1996, Schneeberger et al 1998.…”

Use of the Minimum Spanning Tree Model for Molecular Epidemiological Investigation of a Nosocomial Outbreak of Hepatitis C Virus Infection

“…Nonetheless, the nosocomial transmission of HCV continues to occur (21). Several recent studies provided evidence of patient-to-patient transmission in most of the cases of nosocomial transmission (2, 5, 6, 9, 13, 15-17, 19, 20, 29, 36), although some studies also reported transmission from health care workers to patients and vice versa (10,26,32).In recent years, the use of molecular biology techniques has proven to be a powerful tool in the epidemiological investigation of HCV infection in health care facilities and other settings (2,4,6,9,10,13,15,16,19,20,24,30,32). In particular, phylogenetic tree analysis has often been used to identify the original source of infection.…”

“…In recent years, the use of molecular biology techniques has proven to be a powerful tool in the epidemiological investigation of HCV infection in health care facilities and other settings (2,4,6,9,10,13,15,16,19,20,24,30,32). In particular, phylogenetic tree analysis has often been used to identify the original source of infection.…”