Published online Sep 21, 2015. doi: 10.3748/wjg.v21.i35.10224
Peer-review started: April 1, 2015
First decision: May 18, 2015
Revised: June 6, 2015
Accepted: July 8, 2015
Article in press: July 8, 2015
Published online: September 21, 2015
AIM: To determine the prevalence of infection with hepatitis C virus (HCV) in those most at risk of advanced liver disease and to identify gaps in knowledge of HCV.
METHODS: Questionnaires were mailed to randomly selected residents aged 40-59 to assess the extent of their general knowledge about HCV. The questionnaire assessed demographics, the extent of general knowledge about viral hepatitis, potential risks for infection and the prevalence of risk factors associated with increased progression of liver fibrosis. Anonymised residual laboratory blood samples from 40-59 years old people from Dunedin taken in hospital or in the community, were tested for HCV antibodies and alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transpeptidase (GGT). Linear regression was performed to examine whether the demographics sex, age, socio-economic status, qualification level and occupation sector (categorical variables) were predictors of level of general knowledge about hepatitis. For the demographics that were found to be significant predictors of score outcome, multiple regression analysis was used to determine independent effects. χ2 tests were used to compare our selected sample and our responder population demographics, to the demographics of the entire 40-59 years old population in Dunedin using the 2006 NZ census data. Exact confidence intervals for the proportion positive for HCV and HBV were calculated using the binomial distribution.
RESULTS: The response rate to the mailed questionnaire was 431/1400 (30.8%). On average 59.4% questions were answered correctly. Predictors for higher scores, indicating greater knowledge about symptoms and transmission included sex (female, P < 0.01), higher level of qualification (P < 0.000) and occupation sector (P < 0.000). Sharing intravenous drug utensils was a known risk factor for disease transmission (94.4%), but the sharing of common household items such as a toothbrush was not. 93% of the population were unaware that HCV infection can be asymptomatic. 25% did not know that treatment was available in New Zealand and of those who did know, only 40% assumed it was funded. Six hundred and eighty-two residual anonymised blood samples were tested for HCV antibodies, ALT, AST and GGT. The prevalence for HCV was 4.01%, 95%CI: 2.6%-5.8%. Liver function tests were not useful for identifying likelyhood of HCV infection.
CONCLUSION: Prevalence of HCV in our population is high, and the majority have limited knowledge of HCV and its treatment.
Core tip: It is projected that the public health burden due to hepatitis C virus (HCV) will increase substantially over the next 2 decades and that the mortality related to HCV will triple by 2030. We thus require a marked increase in the identification of patients infected with HCV. Safe and successful treatment of those infected is now imminently possible due to the advent of direct acting antiviral agents (DAAs). The number of diagnosed cases must increase substantially to allow DAAs to become cost effective. Our study estimated that 4.01% of asymptomatic 40-59 years old adults living in Dunedin city are infected with HCV. Most have limited knowledge of HCV and its treatment, therefore if educational and health promotion efforts are to produce maximum results for expenditure, they should be designed and targeted at audiences with lower education levels and low socio-economic status, especially immigrants and unemployed persons.