Screening for hepatitis C

Hepatitis C virus (HCV) is a major cause of liver disease worldwide. Globally, it is estimated that there are 115 million people who have had HCV infection, and 80 million with chronic infection.

According to the HSE’s Health Protection Surveillance Centre (HPSC) there were 652 notifications of hepatitis C in 2016 (14.2/100,000 population). This is a small decrease compared to 2015 (n = 675, 14.7/100,000 population). Although the number of cases of hepatitis C reported has declined by 58% since peak levels in 2007 (n = 1,538), recent trends indicate that levels are stabilising rather than continuing to decrease, the HPSC says. HCV infection has been a notifiable disease in Ireland since 2004. Between 2004 and 2016, 14,107 cases were notified.

National guidelines

According to recently produced Irish guidelines on HCV screening,¹ injecting drug use (IDU) is the major risk factor for HCV in developed countries such as Ireland. Initial infection with HCV is typically asymptomatic or mildly symptomatic. The most common symptoms are loss of appetite, abdominal discomfort, nausea/vomiting, and jaundice. Infection is rarely detected in the acute phase. Between 15%-45% of those infected clear the virus spontaneously, while the remaining 55%-85% of those infected develop chronic HCV infection.

Chronic HCV infection can cause liver inflammation, fibrosis, cirrhosis, liver cancer, liver failure and death. Chronic liver disease symptoms may not be evident for 20 to 30 years until serious liver damage has occurred. For this reason, the guidelines point out, HCV infection is sometimes called ‘the silent killer’. 

Progression to chronic liver disease is associated with excessive alcohol intake, co-infection with hepatitis B virus (HBV) or human immunodeficiency virus (HIV), being male, and older age.

The new guidelines note that advancements in treatment for HCV infection that offer a cure in most cases, and are more acceptable to patients, have led to a significant shift in strategy direction for HCV care and policy, with the paradigm now focused towards elimination.

Where risk factor data are available, IDU is the most common HCV risk factor reported (80%), followed by possible sexual exposure (5%), receipt of blood or blood products (4%), vertical transmission (2%) and tattooing or body piercing (1%). In 7% no risk factor was identified.

Notification data can only include diagnosed cases. Information on the prevalence of a disease is a better reflection of the burden of disease as it includes undiagnosed cases. It is estimated that there are between 20,100 and 42,000 people with current infection in Ireland, and that 60% of those have not yet been diagnosed.

Hospital admissions

The number of hospital admissions due to end-stage liver disease (ESLD) and hepatocellular carcinoma (HCC) in those with HCV infection has been increasing in Ireland. This increase is likely related to the fact that the peak incidence in the largest risk group, people who inject drugs (PWID) in Ireland, was in the late 1990s, and those infected during that period are now developing end-stage liver disease or hepatocellular carcinoma (HCC). Between 2005 and 2016, 116 liver transplants were performed in Ireland in people with HCV infection, accounting for 18% of all liver transplants. 

Direct-acting antiviral (DAA) therapies are now the standard of care for HCV infection, according to the guidelines. In HCV treatment, sustained virological response (SVR) means that the virus is no longer detectable at a defined period after completion of therapy. SVR is regarded as a virological cure and is associated with improved morbidity and mortality. Older treatment regimes induced SVR rates of 40-65%. DAA treatment regimes are of shorter duration, with far fewer side effects, and have SVR rates of over 90%. Further details on the new treatments are available at www.hse.ie/eng/health/az/H/Hepatitis-C/

It is now recommended that DAA regimens be used for the treatment of persons with HCV infection. In order to ensure the most appropriate management of access to these costly new drugs, an Expert Advisory Group was established by the Department of Health (DoH) in 2014, which recommended the establishment of the National Hepatits C Treatment Programme (NHCTP) in the HSE.

 (click to enlarge)

Access to treatment

Access to treatment in Ireland has been introduced through the HSE NHCTP on a phased basis, based on clinical criteria with those having greatest clinical need receiving treatment initially. Criteria for treatment are determined by the HSE NHCTP Programme Advisory Group (PAG). There is currently some controversy over funding for access to treatment programmes under the scheme (see editorial on page 5).

Criteria for access to treatment are continuously expanding, according to the guidelines. “The HSE NHCTP is aiming to provide treatment across a range of healthcare settings to all persons living with HCV in Ireland over the coming years with a view to successfully eliminating the HCV in Ireland and making it a rare disease by 2030,” they state.

In order to achieve this, all at-risk groups must be identified, screened and linked to treatment and care. In order to achieve this, all at-risk groups must be identified, screened and linked to treatment and linked to treatment and care. Implementation of this National Clinical Guideline will be key to the identification and screening of people with undiagnosed HCV infection, the guidelines state.

With the development of new treatments for HCV, the paradigm has shifted towards elimination, the guidelines state. Key to reaching the goal of elimination will be treatment of those infected. However, it is estimated that 60% of those with HCV infection in Ireland are undiagnosed. Without screening, cases may go undetected for a considerable length of time due to the asymptomatic nature of HCV infection, the guidelines stress.

“With the commitment to offer treatment to those infected through the establishment of the HSE NHCTP, there has never been a more important time for national screening guidelines to be introduced,” the guidelines state.

The aim of the new guidelines is to reduce the overall health and economic impact of HCV infection and contribute to the elimination of HCV as a public health concern in Ireland by 2030. The objectives of the guidelines are:

• To make recommendations on who should be offered screening for HCV infection and how screening should be undertaken 
• To enhance and further improve the screening of those at risk for HCV 
• To improve the identification of undiagnosed cases of HCV
• To reduce variation in practice relating to HCV screening to support the linkage to care of identified cases to increase awareness of HCV screening amongst healthcare workers and the public.

Guideline recommendations

Among the main recommendations in the guidelines are:

• There should be standardised targeted risk-based HCV screening of antenatal women. At risk groups include those who have ever injected drugs; migrants from a country with an intermediate and high prevalence of HCV and recipients of anti-D immunoglobulin in Ireland between May 1977 and July 1979 and March 1991 to February 1994 who have not yet been tested
• Universal HCV screening of antenatal women is not recommended. Universal antenatal screening may be considered in the future if HCV treatment during pregnancy becomes possible
• Recipients of blood or blood components in Ireland prior to October 1991 who have not yet been tested should be offered screening
• All recipients of anti-D immunoglobulin in Ireland between May 1977 and July 1979 and March 1991 and February 1994 who have not yet been tested should be offered screening
• Infants of HCV-RNA (ribonucleic acid) positive women should be tested for HCV-RNA at six weeks and six months of age and if both are negative, anti-HCV at 18 months or older
• If a woman has current or unresolved HCV infection, any previous children she had given birth to should be tested for HCV, unless the woman was known to be HCV-RNA negative at time of delivery
•  In general, HCV screening of household contacts with no sexual or vertical exposure to the HCV-positive household member is not necessary, due to low horizontal transmission risk. In certain cases screening may be considered based on clinical judgement
•  All those who have ever injected unprescribed or illicit drugs should be offered screening for HCV, including those who may have only injected once. Retesting of those who test negative should be offered on an annual basis
• Homeless people who have a history of engaging in risk behaviours associated with HCV, or who have a potential HCV risk exposure, should be offered screening
• Migrants from a country with an intermediate to high prevalence of HCV should be offered one-off screening
• In general, HCV screening of sexual partners of known HCV cases is not recommended in heterosexual couples who are both HIV negative
• HIV positive men who have sex with men (MSM) should be screened at least annually for HCV
• Patients on haemodialysis or peritoneal dialysis should be screened, as should patients post kidney transplant
• All new healthcare workers and new healthcare students should be offered screening on a voluntary basis. There should be mandatory HCV screening of all new health workers who perform exposure-prone procedures. 

Reference

1. Hepatitis C Screening. National Clinical Guidelines No. 15. The full guidelines are available at www.hpsc.ie and http://health.gov.ie/national-patient-safety-office/ncec/national-clinical-guidelines/