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original first appeared on: http://smartsexresource.com/health-providers/blog/201608/epidemiology-new-versus-prevalent-hepatitis-c-infections-canada-bc

 

Epidemiology of new versus prevalent hepatitis C infections in Canada: BC Hepatitis Testers Cohort

Introduction

n BC, at least 50,000 people are currently living with active hepatitis C (HCV) infection.[1,2] Left untreated, individuals with HCV have 5 times higher risk of dying from any cause and 20 times higher risk of dying from liver-related causes than uninfected persons.[3]

Newer, well-tolerated drugs (direct acting antivirals) have improved treatment success with cure rates approaching 95% while also reducing side effects. This presents new opportunities to prevent progressive liver disease in the population.  However, treatment alone may not be sufficient for all individuals living with HCV. Some individuals may benefit from complementary programs to prevent liver damage and/or reinfection with HCV.

A large data platform, the BC Hepatitis Testers Cohort (BC-HTC), has been assembled to assess and monitor HCV disease burden, including important co-infections such as HIV, tuberculosis, and hepatitis B and risk factors for liver damage and HCV re-infection.[4]

Based on the BC-HTC, the epidemiology of new and prevalent HCV infection has been described for BC.

Methods

The BC-HTC includes all individuals, since about 1990, that have either tested for HCV or HIV at the BCCDC Public Health Laboratory, or have been reported to public health as a case of HCV, HBV, HIV/AIDS, or active TB. This cohort of over 1 million people is linked with medical visits, hospitalizations, prescription drugs, cancers, and deaths.[4]

We compared two groups of HCV positive cases in terms of age, gender, markers of substance use and mental illness, and social and material deprivation.

HCV positive cases are divided into prevalent cases (those that tested HCV positive at their first test on record), and seroconverters (those that tested positive after a prior negative test). In seroconverters, infection occurred in the interval between the prior negative and first positive test, which suggests that there were risk factors for HCV acquisition during that time. In prevalent cases the timing of infection is unknown but more likely to be decades ago, based on previous explorations of HCV testing patterns.

Summary of evidence

Of the 1,132,855 individuals in the cohort, 67,726 were HCV cases as of the end of 2013. Of these, 11,954 (17.7%) had died.

Comparing the HCV groups, select findings include (see below infographic):

Prevalent cases: Older; more stable living conditions; more liver disease and age-related health issues

  • 88% of all cases. the majority of which (73%) were born before 1965
  • high rates of liver-related illness and death
  • lower prevalence of illicit drug use, mental illness, and HIV coinfection at time of HCV diagnosis
  • lower prevalence of problem alcohol use than seroconverters. However, even low to moderate alcohol use has implications for liver disease progression in HCV infected persons.

Seroconverters: Younger; living with multiple vulnerabilities

  • 12% of all cases, the majority of which (74%) were born after 1965
  • more likely to be coinfected with HIV and be socioeconomically marginalized at time of diagnosis
  • high proportion of this group are living with serious mental illness and/or had evidence of illicit drug use

Infographic: The twin HCV epidemics in Canada

Implications for practice

There are clear differences between older individuals diagnosed with HCV at first test (prevalent cases), compared with younger individuals diagnosed with HCV following previous negative test(s) (seroconverters).

Seroconverters can benefit from a comprehensive approach that integrates:

  • harm reduction
  • treatment and support for mental illness and dependence/addictions
  • treatment for HCV and co-infections, like HIV
  • stable housing and income

This approach will not only prevent HCV reinfection, but will also improve quality and quantity of life.

In contrast, prevalent cases have comparatively lower rates of illicit drug use, mental illness, alcohol use, and HIV coinfection. However, they require immediate linkage to care and assessment for treatment to prevent end-stage liver disease and premature death. Even the moderate prevalence of problem alcohol use suggests that awareness of HCV and strategies to reduce liver damage in infected persons requires improvement.

For further information

See the full publication for more details: http://www.biomedcentral.com/1471-2334/16/334
See the BC-HTC website for further information (patients and health care providers): http://hepatitiseducation.med.ubc.ca/

Acknowledgements

Dr. Naveed Janjua, Dr. Jason Wong, and Maria Alvarez, Clinical Prevention Services, BCCDC

References

  1. British Columbia Centre for Disease Control. British Columbia Annual Summary of Reportable Diseases 2014. Available at: http://www.bccdc.ca/resource-gallery/Documents/Statistics%20and%20Research/Statistics%20and%20Reports/Epid/Annual%20Reports/AR2014FinalSmall.pdf
  2. Janjua N, Kuo M, Yu A, Wong S, Alvarez M, Krajden M. The BC Hepatitis Testers Cohort: The population level hepatitis C Cascade of Care in British Columbia, Canada. Conference Presentation at: EASL: The International Liver Congress 2016. Barcelona, Spain. April 13-17, 2016.
  3. Yu YW, Spinelli JJ, Cook DA, Buxton JA, Krajden M. Mortality among British Columbians testing for hepatitis C antibody. 2013. BMC Infectious Diseases. DOI: 10.1186/1471-3458-13-291. Available at: http://bmcpublichealth.biomedcentral.com/articles/10.1186/1471-2458-13-291
  4. Janjua NZ, Kuo M, Chong M, Yu A, Alvarez M, Cook D, Armour R, Aiken C, Li K, Mussavi Rizi SA, Woods R, Godfrey D, Wong J, Gilbert M, Tyndall MW, Krajden M. Assessing Hepatitis C Burden and Treatment Effectiveness through the British Columbia Hepatitis Testers Cohort (BC-HTC): Design and Characteristics of Linked and Unlinked Participants. 2016. PLOS ONE. Available at: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0150176

original first appeared on: https://smartsexresource.com/health-providers/blog/201305/current-status-hcv-epidemic-british-columbia-and-canada

The current status of the HCV epidemic in British Columbia and Canada

May 8, 2013 by Margot Kuo, Epidemiologist, Clinical Prevention Services, BCCDC

Background

Prevalence and incidence are two basic measures of disease frequency used to inform our response to the Hepatitis C (HCV) epidemic. Prevalence is the total number of people living with chronic HCV infection, while incidence is the number of new infections that occur in that year.

HCV surveillance in British Columbia relies on diagnoses of HCV in BC, which are looked at two ways:

  1. The number of new HCV diagnoses reported each year or first-time HCV positive individuals (reactive for antibody to hepatitis C virus or anti-HCV positive); and
  2. The number of acute cases - new positives with a negative anti-HCV test on record within the prior 12-month period.

These data are imperfect estimates because they only include individuals who have gone for testing, and tests can be done years after initial infection. For HCV incidence, looking at acute cases is a reasonable estimate, but these trends are also influenced by testing behavior (and are more likely to reflect people who test for HCV more frequently).

The Public Health Agency of Canada (PHAC) released a surveillance report summarizing hepatitis C in Canada from 2005 - 2010, based on based multiple data sources. This includes the last release of modeled estimates of HCV prevalence and incidence from 2007. Below we describe findings from the Canadian surveillance report and provide the most recent HCV diagnosis trends from British Columbia surveillance data.

Findings

As a chronic condition, HCV prevalence increases over time as cases accumulate. To understand the scope of problem, in 2007, a model was developed to estimate the number of HCV cases in Canada.

  • It was estimated that 242,521 people were living with HCV in Canada, corresponding to a prevalence of 0.8% of the general population (Table 1). The prevalence of HCV among males was 1.6 times higher than among females.
  • Incidence was modeled at 0.026% or about 8000 persons with newly-acquired infection in 2007. Incidence among males was higher than females and more than three quarters (83%) of incident infections were among persons who inject drugs (PWID).

The annual numbers and rates of laboratory confirmed infections (anti-HCV testing) reported to the Canadian Notifiable Disease Surveillance System (CNDSS) decreased between 2005 and 2009 from 13,017 cases in 2005 to 11,357 in 2009, corresponding to a rate of 40.4 per 100,000 in 2005 to 33.2 per 100,000 in 2009 for Canada. While BC rates are also decreasing, rate of new HCV diagnoses in BC is still higher than most other provinces and the national average (Figure 1).

Incidence in BC, as represented by rates of acute cases, has been decreasing since 2008 (Figure 2). Increases in testing volume (over 130,000 persons tested for hep C in 2011) and repeat testing behaviour (testing more than once) have helped to improve this estimate over time.

Interpretation and implications

The decreasing trend in hepatitis C case reports in British Columbia and Canada is thought to be due to a reduction in transmission/incidence related to decrease in illicit drug injection use and/or low numbers of susceptible (uninfected) persons in the key risk population, PWID. There are various HCV risk groups with varying rates of HCV infections. While PWID are a major contributor to the pool of HCV infected individuals in Canada, other risk factors include:(1)

  • history of haemodialysis,
  • receipt of blood products before 1992 or clotting factors before 1988,
  • exposure to blood of high risk individual,
  • incarceration,
  • unregulated tattoos,
  • immigration from a high-prevalence country and
  • those presenting with HIV and/or persistently elevated liver enzymes (AST).

While current BC specific estimates of HCV prevalence are not available, there may be 60,000 to 80,000 persons infected with HCV in BC, many unaware of their infection. A recent study of British Columbians who underwent anti-HCV testing found high death rates in HCV positive individuals due to progressive liver disease as well as risks related to drug use, street involvement and poverty.(2) In 2011, about one in three HIV positive individuals in BC were also infected with HCV.(3) All of this suggests that British Columbians with hepatitis C have a spectrum of risks, needs, and health outcomes requiring very different prevention and treatment approaches.

At this time, there are multiple initiatives underway to improve provincial HCV and HIV surveillance data and derived estimates by incorporating other information that would confirm infection and link to important health outcomes, such as treatment and mortality, as well as inform prevention initiatives.

Further information

National estimates are presented in more detail in Hepatitis C in Canada: 2005-2010 Surveillance Report.

Provincial estimates of Hepatitis C rates can be found in British Columbia Annual Summary of Reportable Diseases, 2011.

Notes

PHAC = Public Health Agency of Canada
BCCDC = British Columbia Centre for Disease Control
CNDSS = Canadian Notifiable Disease Surveillance Systems
PWID = Persons who inject drugs

Acknowledgements

  • Mark Gilbert, Physician Epidemiologist, Clinical Prevention Services, BCCDC
  • Naveed Janjua, Hepatitis Surveillance Lead, Clinical Prevention Services, BCCDC
  • Travis Salway Hottes, Epidemiologist, Clinical Prevention Services, BCCDC

References

  1. The Society of Obstetricians and Gynaecologists of Canada. The Reproductive Care of Women Living with Hepatitis C Infection. SOGC Clinical Practice Guidelines. 2000.
  2. Yu A, Spinelli JJ, Cook D, Buxton JA, Krajden M. Mortality among British Columbians testing for hepatitis C antibody. BMC Public Health. 2013;13:291.
  3. Klein MB, Rollet KC, Saeed S, Cox J, Potter M, et al. HIV and hepatitis C virus coinfection in Canada: challenges and opportunities for reducing preventable morbidity and mortality. HIV Medicine. 2013;14:10-20.

original first appeared on: http://pacificaidsnetwork.org/2017/03/29/the-hepatitis-c-care-cascade-from-diagnosis-to-care-and-treatment-in-british-columbia/

The Hepatitis C Care Cascade: From Diagnosis to Care and Treatment in British Columbia

At the PAN Fall Conference, we learned from Dr. Lianping (Mint) Ti about short-course direct-acting antiviral (DAA) drugs for hepatitis C (HCV). These well-tolerated drugs have demonstrated cure rates of 95% and have been available in British Columbia (BC) since 2014, but their dispensation has been limited to individuals with advanced liver disease due to their high cost.

Findings from a recently published paper on the population level cascade of care for HCV in BC demonstrate the need for greater access to liver care and treatment for individuals living with HCV. According to Dr. Naveed Janjua and his colleagues, data from the BC Hepatitis Testers Cohort (BC-HTC; click here for more information about the cohort) indicates that as of 2012, only 32% percent of the 54,902 people diagnosed with HCV in BC had accessed liver care. Of these diagnosed individuals, only 12% had initiated treatment for hepatitis C and only 7% had achieved a sustained virologic response, defined as an undetectable HCV RNA level measured twelve weeks after completing treatment.

It is also important to note that Janjua and his colleagues estimate that as of December 31, 2012, 18,301 residents of BC were HCV antibody positive but undiagnosed. While it may seem surprising that an estimated 25% of HCV infections in BC are undiagnosed, Janjua et al. cite a 2011 paper by Maxim Trubnikov and colleagues from the Public Health Agency of Canada that suggests 20–44% of HCV infections in Canada are undiagnosed. These statistics illuminate the need for a testing strategy to reach those who are undiagnosed and, as a result, unlinked to care.

Janjua et al.’s findings on the cascade of care for people living with both HIV and HCV also demonstrate the need for accessible interventions. While HIV and HCV co-infected individuals are 6% of the 52,902 people diagnosed with HCV in BC, they are 10%, or 957 people, of the group of people accessing liver care. Of this 10%, however, only 5%, or 408 people, have ever been dispensed treatment. These numbers demonstrate that about 50% of individuals in the co-infected group fall off the cascade of care between these stages, highlighting the gaps that exist between a positive HCV diagnosis and retention in care and treatment.

Fortunately, options for treatment are about to become more accessible for individuals living with HCV in BC, Ontario and Saskatchewan. In February 2017, the BC Ministry of Health announced that thousands of British Columbians living with hepatitis C will have better access to treatment as a result of negotiations brokered by the pan-Canadian Pharmaceutical Alliance (pCPA) to improve the costs of these drugs for the BC, Ontario and Saskatchewan governments. Starting around March 21, 2017, physicians in BC can apply on behalf of their patients for coverage to a set of more effective HCV drugs.

In March 2018, coverage restrictions related to disease progression will be lifted completely and BC PharmaCare will provide coverage for any British Columbian living with chronic hepatitis C regardless of the type or severity of their disease. In their paper, Janjua and his colleagues explained how access to drugs such as these are “expected to be a game changer in preventing progressive liver disease.”

We can only hope that access to these better-tolerated drugs will help close the gap between diagnosis, care, and treatment for individuals living with HCV in British Columbia, Ontario and Saskatchewan. As Janjua and his colleagues remind us, “for these drugs to have major population-level impact on morbidity and mortality, screening efforts must reach undiagnosed individuals, diagnosed individuals must be linked with care and people remain engaged with care to be assessed for and receive treatment.”