9261 HEPATITIS C REPORT GALLEY - North West Public Health ...

1. INTRODUCTION
1.1 Background
Viruses such as the human immunodeficiency virus (HIV), hepatitis C and hepatitis B
that are transmitted through blood pose a major health threat particularly for people
who inject drugs. Amongst these viruses, hepatitis C represents a growing concern for
several reasons. Firstly, previous studies in the UK and Ireland suggest that its
prevalence is extremely high among injecting drug users (IDUs) (between 60% and
90%: Smythe et al.1998; Goldberg et al. 1998; Lamden et al. 1998; Best et al. 1999).
Secondly, unlike for hepatitis A and B, no vaccine is as yet available, and the rapid
mutation rate of the hepatitis C virus makes the imminent development of one
unlikely (Liang et al. 2000). Thirdly, a high proportion of cases (around 80%) become
chronically infected, and of these, around 20% go on to develop serious liver damage,
such as cirrhosis or hepatic carcinoma (Theodore & Fried 2000). Finally, current
treatment is often ineffective, with even the most advanced treatment available
clearing the infection on only 40% of occasions (Liang et al. 2000).
Key objectives in the Government's ten year drug strategy Tackling Drugs to Build a
Better Britain (1998) include increasing the number of users entering treatment
programmes, reducing the number of young people using drugs and reducing the
levels of injecting and sharing of equipment. If these targets are met, the number of
new hepatitis C infections would decrease. However, currently there are large numbers
of users in the North West who share equipment who are either infected with hepatitis
C or at risk of infection (see Section 1.4). The exact scale of the problem is difficult to
assess as individuals typically have many years of asymptomatic infection before
presenting to health services with chronic disease. What is clear though, is that the
high prevalence among IDUs currently accessing drug treatment services suggests
considerable future health care costs in treating the expected associated rise in liver
failure and associated morbidity (Leal et al. 1999), as well as the health and social costs
of prolonged morbidity and disability to those infected with hepatitis C (Dolan 1997).
1.2 Transmission
Hepatitis C is primarily transmitted through blood. Prior to screening of blood
donations, recipients of blood transfusions or blood products were at risk of infection.
As a result, an estimated 4000 haemophiliacs in the UK have been infected through
blood products (The Haemophilia Society 1999) and the total number of people
infected through blood or blood product transfusion and organ donation is estimated
to be around 7500 (Syed & Snee 1997; CDSC North West 1999). The risk of infection
through this route dropped dramatically with the introduction of effective heat
treatment in 1986 (1987 in Scotland) (The Haemophilia Society 1999). The risk then
dropped further with the introduction of hepatitis C antibody screening in 1991.
The group now at the highest risk is IDUs.
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H EPATITIS C IN INJECTING DRUG USERS IN THE N ORTH W EST