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Although HCV RNA and genotype testing rates have
Although, HCV RNA and (RS)-CPP testing rates have improved in recent years and are similar to those reported for HCV positive Veterans and Kaiser Permanente members in the United States (95%) and higher than for primary care in Canada and United States (47.0% to 60.9%), there is a further need to reduce the gap between those antibody diagnosed and those undergoing further testing (Maier et al., 2016; Jonas et al., 2016; Spradling et al., 2014; Viner et al., 2015). We demonstrated that people with high risk activities progress to RNA testing while men and older cohorts, especially those born in 1945–64 lacked RNA testing (Spradling et al., 2014; Cachay et al., 2014). A major factor for lack of genotyping among those RNA tested was history of drug use. Data from Canada and other countries suggest that lack of knowledge among primary care physicians, especially those not involved in providing care to those with known risk activities, regarding next steps in the cascade and poor knowledge among patients are associated with the gap from HCV diagnosis to RNA testing (Butt et al., 2013; Grebely et al., 2013; Guirgis et al., 2012). Although guidelines and education for primary care physicians are important instruments to bridge this gap, a single blood sample test strategy in which those testing positive for antibody are also tested for RNA (reflex testing) and possibly for genotype could be an effective structural intervention to bridge this gap. Reflex testing for RNA has been implemented in the VA system and recently in Kaiser Permanente system, and was associated with higher RNA testing rates (Maier et al., 2016; Jonas et al., 2016). Despite a robust testing continuum for those accessing screening, BC remains similar to the US, Australia and other countries in initiating treatment (Maier et al., 2016; Viner et al., 2015; Lazarus et al., 2014; Hajarizadeh et al., 2016). We found that a small proportion (15%) of HCV diagnosed individuals initiated HCV treatment by 2012. Those who did not progress to treatment, even while in liver care included those with HIV coinfection and people currently engaged in illicit drug use. Factors related to poor tolerability and efficacy of interferon based treatments along with other factors at the patient (poor knowledge, unemployment, competing priorities, stigma, lack insurance and provider relationship), provider (perception of poor adherence, ongoing substance use, psychiatric illness, potential re-infection) and, system (lack of consensus on screening and treatment and coverage of HCV treatments) levels have been reported to be associated with lower treatment rates in these populations in Canada and other settings (Grebely et al., 2013; Aspinall et al., 2013). DAAs are expected to overcome some of these barriers, though high drug costs may affect reimbursement coverage. Despite comprehensive data available to us for characterization of the cascade of care, there are several limitations that impact each stage. The estimate of prevalent HCV cases is based on the number of HCV undiagnosed cases derived in a national model based on reported cases and survey data (Trubnikov et al., 2014). Historically, BC has tested more individuals for HCV(by December 2014, 33% of BC\'s population has been tested at least once) than other provinces and in recent years testing volumes have increase substantially, suggesting our undiagnosed proportion may be lower than the national average (Consolacion et al., 2015). We have also seen decline in HCV positivity among baby boomers from 13% in 2001 to 2% in 2013, suggesting declining pool of undiagnosed individuals in BC (Janjua et al., 2016b). All these data suggest lower percentage of undiagnosed individuals in BC than national average. In our evaluation of those requiring ongoing monitoring and care, we excluded those with patterns suggesting outmigration. While unlikely, a small proportion of these people may still be in the province but not accessing care. We used diagnostic codes in administrative datasets to assess history of mental illness and substance use. This raises multiple issues: bias towards underestimating prevalence in those less engaged in healthcare, and potential misclassification related to sensitivity and specificity of these measures. Potentially lower linkage rates in vulnerable groups would result in less representation of homeless, street-involved, and incarcerated individuals (Janjua et al., 2016a).