Hepatitis C virus genotypes in a cohort of Australian blood donors and haemophiliac and liver transplant patients

Abstract

The aim of the present study was to characterize hepatitis C virus (HCV) genotypes using the INNO-LiPA HCV line probe assay and direct sequencing from three different HCV-RNA-positive (serum) groups: (i) blood donors (n = 59); (ii) haemophiliacs (n = 43); and (iii) patients undergoing liver transplantation (n = 26). Of 128 HCV-RNA-positive samples, 74 (58%) were genotype 1. Of these, 41 were genotype 1a, 32 were genotype 1b and one was genotype 1 indeterminate. Of the remaining 54 samples, seven (5%) were genotype 2a, two (2%) were genotype 2b, 26 (20%) were genotype 3a, three (2%) were genotype 4a, while 16 (12.5%) were of a mixed genotype. There was no significant difference between the three groups with regard to the prevalence of any specific genotype. However, in blood donors and haemophiliac patients there was a statistically significant difference in the occurrence of genotype 3a in patients with elevated alanine aminotransferase (ALT) levels (30.3%) compared with those patients with persistently normal ALT levels (5.6%; P = 0.004; chi 2). Genotype 3a was also uncommon in liver transplant patients (one of 14) with "sporadic' HCV infection. Genotype 4a was detected only in liver transplant patients. These patients had originated from Egypt (n = 1), Italy (n = 1) and Romania (n = 1).

Incident Hepatitis C Virus Genotype Distribution and Multiple Infection in Australian Prisons

“…Previous prevalence surveys of chronic HCV infection in Australia between 1997 and 2000 resulted in reported ranges of 20% to 38% for genotype 3 and 52% to 65% for genotype 1 (18)(19)(20)(21)(22)(23)(24). In contrast to those studies, the findings reported here indicate an apparent increase in the transmission of genotype 3 (51% of incident infections).…”

“…It should also be noted that the data presented here were based on the use of a sensitive, subtype-specific assay system for detection of multiple infections which also incorporated both longitudinal time points and a relatively large sample size. This more comprehensive analysis may explain the higher rate of multiple infection seen in this study compared to others (19,20,22,25,48). It is also worth noting that this cohort was analyzed using samples collected in the custodial setting, which may impose risk factors that are different from rates of mixed infection that are higher than those seen with IDUs based in the community (16).…”

“…Genotype 4 is prevalent in the Middle East and Africa, and high prevalences of genotypes 5 and 6 have been reported in South Africa and Asia, respectively (17,18). The genotypes most commonly reported among chronically infected individuals in Australia are genotypes 1 (52% to 65%) and 3 (20% to 38%), with low prevalences of genotypes 2, 4, and 6 (approximately 5% to 9%, 0% to 6%, and 0.6% to 2%, respectively) (19)(20)(21)(22)(23)(24)(25). It should be noted, however, that these prevalence surveys were conducted in the 1990s and predominantly screened chronically infected individuals who had likely contracted the virus years to decades prior to testing; therefore, the results of those studies do not necessarily represent the viruses currently being transmitted (26).…”

“…Multiple infections (i.e., simultaneous or sequential infections with two or more HCV strains) are common, with reported prevalence rates in Australia ranging from 0.7% to 25% (16,19,20,22,25,27). The highly diverse nature of HCV strains and limited cross-genotype protective immunity (28), in combination with the high risk of reexposure through ongoing IVDU, are believed to contribute to the occurrence of multiple infections.…”

Liver transplantation for HCV-associated liver cirrhosis: Predictors of outcomes in a population with significant genotype 3 and 4 distribution

“…Samples that were HCV antibody-positive (second generation test) and HCV-RNA-negative were tested further with nested polymerase chain reaction (PCR) for the NS5b region as described previously. [14][15] …”