The association between use of non-injection drug implements and hepatitis C virus antibody status in homeless and marginally housed persons in San Francisco.

BACKGROUND: Up to 17,000 persons in the USA became infected with hepatitis C virus (HCV) in 2007, and many cases have unknown transmission routes. To date research on transmission of HCV via shared implements used to snort or smoke non-injection drugs has been inconclusive.

METHODS: We tested stored sera for HCV antibodies (anti-HCV) in a large population-based study of homeless and marginally housed persons in San Francisco. We examined the association between sharing implements used for snorting and smoking drugs and anti-HCV while controlling for sociodemographic variables in those who denied ever injecting drugs (n = 430). We also examined the association of anti-HCV status with history of incarceration, tattoo and piercing history, sexual history and alcohol consumption.

RESULTS: Seventeen percent of our sample was anti-HCV positive. We found no statistically significant associations with sharing implements used to smoke or snort drugs with anti-HCV status in our various multivariate models. There was a statistically significant negative association between ever snorting cocaine and anti-HCV status (adjusted odds ratio: 0.39; 95% confidence interval: 0.21-0.73). There were no other statistically significant associations with any other measured covariates in multivariate analyses.

CONCLUSIONS: Our findings suggest that sharing implements to snort or smoke drugs is not a significant risk factor for anti-HCV-positive status.