Identification and genotyping of hepatitis C virus in injectable and oral drug users in New Zealand.

BACKGROUND

Hepatitis C virus infections are known to be common in injectable drug users (IDU) both in New Zealand and overseas. Little is known of the hepatitis C genotype frequency in this population.

AIMS

To confirm the high incidence of hepatitis C virus infections in IDU and compare this with the frequency in oral drug users (ODU) as well as identify the pattern of hepatitis C genotypes present.

METHODS

Use was made of an experimental nucleocapsid assay as well as a conventional anti-HCV assay. HCV-RNA was identified using a polymerase chain reaction (PCR) technique and a variation of this method was used for HCV genotyping.

RESULTS

Seventy-four per cent of IDU were reactive for anti-HCV in both types of assay. PCR testing detected several more reactive samples. Dominant genotypes were Types I and V, but Type IV was not detected. Mixed infections were noted in some patients. There was a low frequency of anti-HCV in ODU.

CONCLUSIONS

Hepatitis C virus infections are a problem in IDU in New Zealand, and additional public health measures may be required. The distribution of genotypes of HCV-RNA are similar to those seen in other Western countries.