injecting drug use and blood borne virus transmission in wales: building the evidence base

Injecting drug use and blood borne virus transmission in Wales: building the evidence base

Project teamICDS

Dr Marion Lyons

Dr Noel Craine

Dr Mark Walker

Josie Smith

Zoe Couzens

HPA

Dr John Parry & Tamara Mcdonald

Imperial College

Dr Mathew Hickman

Cardiff University

Dr Barry Nix

Informing the blood borne virus strategy for Wales

Future burden of disease?

How effective are interventions to reduce transmission?

What service developments are needed across Wales?

Research into current prevention and service development in Wales

qualitative study of needle and syringe exchange provision (collaboration Imperial College London and WIRED) - using grounded theory approach – addressing barriers to NSE uptake and availability

South and West Wales - street recruited needs assessment

provision of HBV and HCV services in primary and secondary health care settings across Wales

Prevalence and incidence of HCV, HBV and HIV amongst IDUs

South Wales HCV Incidence Study – prospective cohort study of injecting drug users

– determine factors behind the patterns of incidence and prevalence

– provide baseline data to monitor impact of intervention

– inform estimates of future disease burden

Newport (134)

Pontypridd / Rhydfelin (37)

Cardiff (200)

Caldicott (17)

Bridgend (51) Barry (15)

Abergavenny (11)

Aberdare (9)

Swansea (97)

Neath (31)

Merthyr (95)

North West Wales Salivary Survey (153)

Treorchy (17)

Sample sites and sample sizes

Age profile of total sample of 717

0

40

80

120

160

16 20 24 28 32 36 40 44 48 52 56

age

n. of individuals

Sample characteristics

male – 73%, female – 26%

54% of sample in substitution treatment

(proportion varied across sample)

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

Swanse

a

Neath

Bridge

ndBar

ry

Cardif

f

Mer

thyr

Aberd

are

Rhond

da

Newpo

rt

Caldico

tt

Aberg

aven

ny

% receiving substitution treatment

Preliminary findings

• anti-HCV - 26.8% (95% CI 24%-30%)

• anti-HBc was 9.8% (95% CI 8%-12%)

• both markers together - 7%

• anti-HCV 6.1% (95% CI 2.1%-14.3%) amongst injectors

who had been injecting for one year or less.

• 539 HCV seronegatives for follow up

• no significant difference in prevalence between males and females

HCV and HBV - age prevalence curves for all sample (95%CI)

age group

prevalence

Duration of injecting, anti-HCV and anti-HBc prevalence

sample site (West to East)

prevalence %

Anti-HCV prevalence by site ordered West to East (95%CI fitted)

Mean anti-HCV prevalence – all South Wales sample (95%CI)

Merthyr Tydfil

CardiffSwansea

Between site comparison – duration of injecting and HCV prevalence

HCV testing and HCV positives

25% of dried blood spot positives knew they were positive from previous test

24% of dried blood spot positives reported a previous negative test result

the remaining dried blood spot positives were either untested, didn't know result or didn't know if they had been tested

HBV vaccination across sample

0.0

10.0

20.0

30.0

40.0

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70.0

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100.0

mean

HBV vaccination of IDUs

• prisons 65%

• GPs 15%

• other drug services 8%

• GUM 7%

• other 5%

40% of anti-HBc positive individuals - vaccinated

The next stage

• follow up and re-sampling of cohort planned Dec / Jan

• include HIV testing at follow-up

• roll out of anonymous unlinked salivary monitoring program

• look at the role of prisons

How can we use this research to reduce transmission?

early acquisition of infection

regional variation – highlights potential for prevention

baseline to assess impact of intervention

large scale peer education program – needle and syringe sharing is common and needs to become rare

HCV – age group prevalence for Cardiff, Swansea and Merthyr