1 IN 4 PEOPLE UNDER 25 YEARS OF AGE WILL BE EXPOSED TO THE HEP C VIRUS. Overall 1 in 2 people attending needle exchanges have been exposed to the Hep C virus

Safer Using - what does it mean?

Safer using essentially includes a series of practices and precautions aimed at the prevention of harm through drug use.

Harm from drug use can manifest in a physical, psychological, legal, or social form. While such harms can never be completely eliminated the NZ NEP has strategies for addressing drug related harms within the framework of harm minimisation.

Aside from the obvious role of needle exchanges, (providing IDU with access to clean injecting equipment and disposal of used equipment), the program also provides information and education related to the full spectrum of harms associated with drug use.

Typically a client of a NEP in New Zealand would expect to find information, advice and products related to minimising the following drug related harms:

  • Prevention of blood borne viruses and bacterial infections.
  • Wheel filters for the prevention of harmful contaminants passing into the body from injecting drugs.
  •  Hirudoid™ cream for care of bruising from injecting drugs.
  • Vein care advice.
  • Overdose protocols and advice.
  • Legal rights advice.
  • Education surrounding harmful drug side-effects, (often from inappropriate self-administration)
  • Advice for poppy season.
  • Medical referrals.
  • Outreach teams.
  • The ability of an IDU to practice safer injecting is directly dependent on the drug injecting taking place within an infrastructure that provides: Non partisan political support for harm reduction.
  • Government policy which provides accessible health and drug service
  • Prevention of blood borne viruses and bacterial infections.
  • Wheel filters for the prevention of harmful contaminants passing into the body from injecting drugs.
  • Hirudoid™ cream for care of bruising from injecting drugs.
  • Vein care advice.
  • Overdose protocols and advice.
  • Legal rights advice.
  • Education surrounding harmful drug side-effects, (often from inappropriate self-administration)
  • Advice for poppy season.
  • Medical referrals. 
  • Outreach teams.
  • The ability of an IDU to practice safer injecting is directly dependent on the drug injecting taking place within an infrastructure that provides:
  • Non partisan political support for harm reduction.
  • Government policy which provides accessible health and drug service falls under the umbrella of the Community Alcohol and other Drug Service and is accessible in most of the larger cities and towns where the number of opiate dependent people in the local population justifies its existence. In smaller communities the drug substitution programme may be coordinated and administered by the District Health Nurse. Those patients who become stable and comply with the programme guidelines may transfer to G.P. authority to receive their medicine from their Doctor.

History

Hepatitis C infection probably entered New Zealand in the late 1960s and early 1970s and spread rapidly among people who injected illicit drugs. However, it was not until late 1991 when the hepatitis C antibody test became available here that the extent of the hepatitis C epidemic in New Zealand began to be described.

While the initial focus of subsequent policy response was on prevention of medically-acquired hepatitis C, it was to take longer for the development of a response to the other main group of people affected by hepatitis C, those who acquired it through injecting drug use. The Ministry of Health’s Action Plan on Hepatitis C Prevention was released in 2002.

SURVEILLANCE OF ACUTE HEPATITIS C INFECTION

Medical practitioners in New Zealand are required by the Health Act (1956) and it’s Infectious Diseases Regulations (1983) to notify cases of specified infectious diseases to their local Medical Officer of Health. Public Health Units collate the data on behalf of the Ministry of Health which maintains a national perspective.

Notification data forms the basis of routine communicable disease surveillance, but it has important limitations with regard to the picture it provides of the epidemiology of hepatitis C in New Zealand. Some of these limitations arise from the nature of the disease itself, others from the case definitions used and the routine mechanisms of data collection.

Notifiable disease surveillance for acute hepatitis C infection.

Given the usual relatively minor or asymptomatic clinical presentation of acute hepatitis C infection, only a minority of infected people will present to their doctors during the acute phase of their infection.

Hepatitis C has been a notifiable disease in New Zealand since 1993. Over that time, three different case definitions have been in use and since 1996, between 60 and 100 cases have been notified per year. The current case definition (adopted in 1999) is:

Demonstration of documented seroconversion to hepatitis C when the most recent negative specimen was within 12 months

OR

Demonstration of an anti-hepatitis C positive test, or positive hepatitis C-RNA test, and a clinical illness consistent with acute hepatitis C within the last 12 months where other causes of acute hepatitis can be excluded.

Notifications of acute hepatitis C are known to underestimate the actual number of new infections each year. The extent of this underestimation is unknown, though one study done by the Auckland Public Health Service in 1997 suggested that, at best, notified cases represent only 40% of the acute cases diagnosed.

EXPOSURE DATA FROM SURVEILLANCE

Although routine notification data is not particularly useful for measuring incidence, trends in notifications and exposure categories for notified cases still provide useful information:

For example, since the screening of donated blood for hepatitis C began in 1992, there have been no notified cases of acute infection resulting from transfusion of blood or blood products.

It is also clear that routes of infection other than injecting illicit drugs now account for only a minority of all notified cases. Injecting illicit drugs is the dominant route of infection in 90% of cases.

Both demographic and exposure data for notified cases are also consistent with what has been found in Australia where the epidemiology of hepatitis C is broadly similar to New Zealand.

People who inject drugs (PWID) are a population at high risk from blood-borne virus infections, particularly human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV). New Zealand’s Needle Exchange Programme (NEP) outlets have taken part in four previous cross sectional surveys of risk behaviours and prevalence of blood-borne viral infections among injecting drug users. These surveys were conducted in 1997, 1998, 2004 and 2009. All found a low prevalence of HIV (<1%) and a high prevalence of HCV (53% in 1997; 45% in 1998; 70% in 2004; and 52% in 2009). Prevalence estimates of immunity to HBV in these surveys were based on self report in 1997, 1998 and 2009 while the 2004 and the current study used paired venous and DBS bloods to determine the key serological markers in assessing HBV immunity, infection and vaccination within this population.

The previous NEP serosurveys provided baseline data against which the contemporary demographic characteristics, injecting and sexual behaviours and seroprevalence of HCV, HBV and HIV in PWID clients of needle exchanges could be compared. Tracking the prevalence of risk behaviours and the prevalence of blood-borne virus infection among PWID is necessary to provide policy and planning direction, and to assess the extent to which harm reduction strategies have been successful. Targeting those that attend dedicated Needle Exchanges also provides a direct contractual measurement of the primary aim of this service or Programme, that is, the prevention of BBV transmission in people who inject drugs that use this service.

During the month of November 2013, PWID clients attending needle exchanges in eighteen selected sites were invited to complete an anonymous questionnaire, and provide finger-prick blood samples. Venous blood samples from nine sites were taken for cross matching of fingerprick dried blood spot (DBS) samples. The eighteen sites (in fifteen areas, e.g. three Auckland and two Christchurch sites) involved in this survey included four previously involved in 1997, 1998 and 2004 (Auckland, Wellington, Nelson and Christchurch), four more included in 2004 (Hamilton, Palmerston North, Timaru and Dunedin), three included in 2009 (Napier and Invercargill, and the mobile outreach NEX on the West Coast of the South Island), as well as needle exchanges from Whangarei, Rotorua and Mt. Maunganui. Seven hundred and sixteen people completed questionnaires during the two-week study period. Four hundred and fifty-two (63%) were male, 257 (36%) female, and 7 (0.1%) transgender. The mean age of respondents was 40 years. Eleven percent of the sample identified as Māori and 2.4% as Pasifika. Just over 10% of respondents identified themselves as bisexual and 1.9% as homosexual.

Completed questionnaires and testable matching blood samples (DBS) were obtained for 689 people (including 194 matched venous/ DBS samples to compare manual and automated testing methods). Of all DBS samples there were 27 samples of insufficient quality for testing: 17 provided equivocal results for HCV, 14 for HBcAb, 118 for HbsAb and 2 for HBsAg.  Two respondents tested positive for HIV (0.2%) and there were no equivocal results. The prevalence of HCV was high (58.3%), a non-significant increase from 2009 (p=0.28) once corrected for all other associations. HCV was associated with age and strongly associated with duration of injecting. Higher rates of HCV were found in those with a history of imprisonment (Odds Ratio [OR]: 2.10) and those who had been on a methadone programme (OR: 3.57). No association was found between HCV status and gender, ethnicity or recent injecting behaviours. Eighty-two percent of respondents reported having been previously tested for HIV, 89% for HCV and 59% for HBV.

Respondents’ mean duration of injecting history was 19 years, and their frequency of injecting was variable, though almost half (48%) injected daily or more often. The drugs most frequently injected by respondents were methadone, morphine, amphetamines and methylphenidate (Ritalin®) and they most often injected in their own (93%) or in friends’ homes (39%). Just under half of the respondents (47%) were currently on a methadone programme, with an additional 17% having been on one previously.

Sixty-six percent of the respondents reported using a new needle and syringe every time they injected drugs and another 27% reported doing so most of the time. Sharing of other equipment such as spoons and tourniquets was reported by over 45% of respondents. Most respondents (84%) had not been injected by someone else after that person had injected themselves, and less than 10% had reused someone else’s needle or syringe at some time in the previous month. Similarly, 90% of respondents had not let someone else reuse their needle and syringe in the previous month, and those who did so mostly shared with their regular sex partner or a close friend.

Half of respondents (49.6%) had had sex in the previous month, although less than a quarter (23.6%) reported using a condom the last time they had sex. Approximately one quarter (27%) of the respondents did not use condoms at all with new sexual partners, or with casual sexual partners. Forty-two respondents had been paid for sex in the last month, almost all of whom (90%) had used condoms the last time they were paid for sex. The majority of respondents had tattoos (74%) and over half had body piercings (56%). Forty-three percent of respondents had been imprisoned at some stage in their lives, nearly a tenth of whom had been imprisoned in the last year. Of these respondents, 29% reported having injected drugs while in prison.

The PWID population who use needle exchanges in New Zealand appear to be aging. The mean age of the 2013, 2009 and 2004 respondents was 40, 38 and 36, respectively, compared to 29 in the 1997 and 1998 surveys. Compared to earlier surveys, the older age distribution observed in 2004 was thought likely to have caused an overestimate of the prevalence of HCV infection for the survey of that year. However, the similar older age distributions observed in 2013 and 2009 does not support that reasoning, with the more probable primary explanation now being the deployment of the free 1-4-1 service (implemented at the approximate time of the 2004 survey). The gender distribution and sexual orientation of respondents were broadly similar across the five studies. While the distribution of ethnicity was similar for NZ European and Māori between 2004 and 2009, for the 2013 survey this dropped from the earlier 14% to 11%, slightly less than the national average. Comparison of ethnicity with earlier surveys is made difficult by uncertainty about previous ethnicity coding.

The rate of HIV has remained low in all five serosurveys (1% or less). The major difference in this study is the small non-significant increase (p=0.28) in HCV prevalence among respondents, compared to 2009. The overall prevalence of HCV was measured at 58.8%, lower than the 70% observed in 2004, and while closer to the prevalence of the earlier surveys, slightly higher than the 52% observed in 2009.  As was the case with the 2009 sample relative to earlier surveys, the 2013 survey was larger, more geographically diverse and the mean ages and duration of injecting slightly higher than those observed in 2004. Moreover, the blood analysis regime was revised, due to advances in testing techniques. For these reasons, as noted above it seems increasingly unlikely therefore that age explains the high HCV prevalence observed in 2004. These characteristics of the 2013 survey method and its sample also mitigate the magnitude of the reported increase in HCV seropositivity for the survey, as they potentially act as confounders in a comparison between it and 2009 data. Possibly substantiating this is the prevalence of HCV in PWID aged under 25 years which, while still high, is the lowest of all the serosurveys (24% in 2013, compared with 27% in 2009, 38% in 2004, 32% in 1998 and 40% in 1997). Prior to the current study, the 2004 study was the only one to test for HBV, so there is no comparative serological data from either the 1997 or 1998 surveys or the 2009 survey. Comparisons of the rate of self-reported vaccination against HBV show this decreasing since 2004..

There have been changes over time in the drugs most frequently injected by respondents. These are likely to reflect changes in the illicit drug market although this is tempered by the profile of a person who injects drugs in NZ as poly-drug and that there is considerable crossover between drug types.

Although a considerable decrease in rates of the sharing of injecting equipment other than needles and syringes was observed in 2004 compared to the previous surveys, reported sharing of spoons, tourniquets and water in 2009 surpassed levels reported in 1998. There has been a steady decline in reported rates of reuse of someone else’s syringe, and the proportion of participants reporting the use of new needles and syringes for all injections has significantly increased over time, from 40% in 1997 to 70% percent in 2009 and unfortunately a slight decrease of two percentage points in 2013. However, combined with an increase in using a new needle/ syringe most of the time means the collective figure of 94% (compared with NEP Review 2002 and NEP Review 2008, Aitken et al., 2002 and 2008 unpublished report)) shows this indicator to be relatively stable. Greater access and availability of injection equipment (including associated equipment other than needles/ syringes) is a vital factor in reducing HCV prevalence, as is the building of positive relationships between Opioid Substitution Treatment (OST) providers and NEP outlets on a regional and national level.

The main conclusions of this survey are that:

•              There has been a slight non-significant increase in the seroprevalence of HCV among PWID using needle exchanges between 2009 and 2013. With the association between age and injecting career length with HCV exposure accommodated, other demographic characteristics of survey participants were eliminated. This leaves the possibility that changes between the two studies in other factors may be associated with trends in risk factors aligned with HCV transmission.

•              Prevalence of HCV-antibody in PWID was associated with older age, longer duration of injecting, and a history of imprisonment, methadone treatment, tattooing and piercing. 

•              Body piercing emerged as a significant risk factor alone for the first time in NEP seroprevalence studies, despite a decrease in last-year piercings.

•              The prevalence of HIV among PWID using needle exchanges remains very low with the 2013 result the lowest ever recorded among NEX attendees. Additionally there is evidence of co-infection with HCV and this increases the complexity of care and outcomes for co-affected individuals. Ongoing collaboration between organisations that target at-risk populations for BBV transmission and acquisition remains vital. 

•              Most PWID using needle exchanges had been tested for HCV and HIV, though many were unaware of, or did not understand their results.

•              An increasing proportion of the PWID in this survey reported no vaccination for HBV and is at risk of infection.

•              There is evidence of some positive change in injecting behaviours; however there has been a slight non-significant decrease in the reported use of new needles and syringes for every injection.

•              There is evidence of considerable decreases in sharing of injecting equipment other than needles and syringes, in some cases to the lowest levels recorded since data collection began.

•              Risky sexual behaviour is still highly prevalent among PWID, with unprotected sex significantly higher than in 2009. Nonetheless, this alone was not correlated with increased exposure to HCV, suggesting the principal focus on prevention should remain with injecting risk behaviours and direct transmission control via injection equipment coverage (accessibility and availability).

•              For the first time in New Zealand, data on injection-related injuries and diseases (IRIDs) were collected. These revealed high prevalence rates for a number of diseases and injuries, with overall 73.6% (n=522) of 709 respondents reporting experience of at least one symptom ever.

•              The survey’s lower level of participation by PWID identifying as Māori, relative to previous surveys, is of concern.

PREVALENCE AND INCIDENCE IN PEOPLE WHO INJECT DRUGS

There have been twelve New Zealand studies of hepatitis C in injecting drug users since 1990.

Six of these involved drug treatment settings like methadone clinics. The prevalence of hepatitis C antibodies was found to be between 67-100% (most between 75-85%) in groups of injecting drug users in treatment settings (most of who have been injecting frequently for some time before entering treatment).

Injecting drug users recruited in non-treatment centres like needle exchanges, had a lower prevalence of hepatitis C antibodies, between 30-80% (most 30-50%).

The three studies taken in the last five years of injecting drug users under 25, showed at least a third had hepatitis C on initial testing.

Only three New Zealand studies have estimated the incidence of hepatitis C among injecting drug users (during the years 1994-1996, 1995-1998 and 1999-2001). All found a high incidence (between 10 and 15 cases per 100 people per year) comparable to that found in Australian injecting drug users.

Hepatitis C continues to spread among injecting drug users in New Zealand, while HIV does not because:

Hepatitis C was already highly prevalent among injecting drug users before harm reduction measures, like needle exchanges were established here.

Hepatitis C is more infectious compared with HIV.

Although there is good evidence from local studies that injecting drug users have adopted safer injecting practices as a result of awareness and education of the HIV/AIDS risk, the extent of this behaviour change has not yet been sufficient to control the spread of hepatitis C.

HEALTH CARE COSTS OF HEPATITIS C IN NEW ZEALAND

Dr. Ian Sheerin, a Health Economist at the Christchurch School of Medicine, has estimated that, based on what is currently known about the epidemiology of hepatitis C in New Zealand and costs of currently available treatments, the health system costs of hepatitis C-related liver disease will be between $166-400 million over the next 30 years.

The initial annual costs are low but they will rise to an estimated $30 million in 2025.

Most of these costs relate to treatment of end stage liver disease, including liver transplantation.