Professor Louisa Degenhardt and Dr Sarah Larney – Global epidemiology of injecting and blood borne viruses among people who inject drugs, and coverage of key interventions

Event type: 
Event date: 
Tuesday, 1 May 2018 - 12:30pm to 2:00pm
Berg Family Foundation Seminar Room, Level 6, Wallace Wurth Building, Kensington Campus, UNSW Sydney
Contact for bookings: 
Rata Joseph, +61 (2) 9385 0900 or
Booking deadline: 
Monday, 30 April 2018 - 10:00am

Kirby Institute Seminar Series presents

Professor Louisa Degenhardt

Professor Louisa Degenhardt

Scientia Professor,  National Drug and Alcohol Research Centre, NHMRC SPRF

Professor Louisa Degenhardt is a UNSW Scientia Professor and NHMRC Principal Research Fellow at the National Drug and Alcohol Research Centre (NDARC), Faculty of Medicine, UNSW. She was awarded her PhD in 2003, examining the comorbidity of drug use and mental disorders in the Australian population. She has honorary Professorial appointments at University of Melbourne’s School of Population and Global Health, Murdoch Children’s Research Institute, and University of Washington’s Department of Global Health in the School of Public Health. Louisa conducts diverse epidemiological studies including analysis of large-scale community and clinical population surveys, data linkage studies focusing upon people with a history of drug dependence or chronic pain, and cohort studies of young people.

Dr Sarah Larney

Dr Sarah Larney

Scientia Fellow, National Drug and Alcohol Research Centre, NHMRC CDF

Dr Sarah Larney is a Senior Research Fellow at the National Drug and Alcohol Research Centre (NDARC), University of New South Wales, and a Research Associate at the Alpert Medical School, Brown University. Her research focuses on injecting drug use and related problems - including problems that arise from injecting (e.g. HIV and hepatitis infections; bacterial infections; injecting injuries), and problems arising from the types of drugs injected (opioid use disorder and its treatment; methamphetamine-related health problems). She works to generate high-quality epidemiological data on injecting drug use and related problems in Australia and internationally, and to use these data to a) improve the safety, efficiency and targeting of current responses to injecting drug use, and b) to develop new responses to neglected harms (e.g. skin infections) of injecting drug use. 


Global epidemiology of injecting drug use

Background: Sharing of equipment used for injecting drug use (IDU) is a substantial cause of disease burden and contributor to blood borne virus transmission. We undertook multiple global systematic reviews to identify prevalence of IDU among people aged 15-64 years; sociodemographic characteristics of and risk factors for people who inject drugs (PWID); and HIV, hepatitis C (HCV) and hepatitis B (HBV) prevalence amongst PWID. 

Methods: Consistent with GATHER and PRISMA guidelines, we systematically searched peer-reviewed (Medine, Embase, and PsycINFO), internet, and grey literature databases, and disseminated data requests to international experts and agencies. We searched for data on IDU prevalence, characteristics of PWID including gender, age, and sociodemographic and risk characteristics, and prevalence of HIV, HCV and HBV among PWID.

Findings: We reviewed 55,671 papers/reports, with data ultimately extracted from 1,147 eligible papers/reports. Evidence of IDU was documented in 179 out of 206 countries/territories covering 99% of the population aged 15-64 year), an increase of 31 countries (predominantly in Sub-Saharan Africa and the Pacific Islands) since a 2008 review; IDU prevalence estimates were identified in 83 countries. We estimate that there are 15∙8 million (uncertainty intervals (UI) 10∙1-24∙2 million) PWID aged 15-64 years globally, with 3∙2 million women and 12∙6 million men. Gender composition varied by location: in North America and Australasia women were estimated to comprise 30∙0% and 33∙4% of PWID respectively, compared to 3∙1% in South Asia. Globally, we estimate that 16∙9% (UI 9.9-24∙6%) of PWID are living with HIV; 52∙5% (UI 41.9-63.3%) are HCV-antibody positive and 8∙9% (UI 4.7-13.9%) HBsAg-positive; there is substantial geographic variation in these levels. Globally, we estimate 82∙9% (UI 76∙6-88∙9%) of PWID mainly inject opioids, and 29∙2% (UI 22∙5-36∙2%) mainly inject stimulants. We estimate that around one in four PWID globally are under 25 years old (27∙8%; UI 20∙8-36∙6%), one-fifth recently (≤past year) experienced homelessness or unstable housing (21∙6%; UI 15∙8-27∙8%), and six in ten have experienced incarceration (58∙0%; UI 50∙6-65∙2%). 

Interpretation: IDU has been identified in more countries since 2008, largely in low- and middle-income countries in Africa. Across all countries, a substantial number of PWID are living with HIV and HCV, and are exposed to multiple adverse risk environments that increase health harms.

Global coverage of key prevention interventions for people who inject drugs

Background: People who inject drugs (PWID) are a key population affected by the global HIV and hepatitis C virus (HCV) epidemics. HIV and HCV prevention interventions for PWID include needle and syringe programmes (NSP), opioid substitution therapy (OST), HIV counselling and testing, HIV antiretroviral therapy (ART), and condom distribution programmes. We aimed to produce country-level, regional, and global estimates of coverage of NSP, OST, HIV testing, ART, and condom programmes for PWID.

Methods: We completed searches of peer-reviewed (MEDLINE, Embase, and PsycINFO), internet, and grey literature databases, and disseminated data requests via social media and targeted emails to international experts. Programme and survey data on each of the named interventions were collected. Programme data were used to derive country-level estimates of the coverage of interventions in accordance with indicators defined by WHO, UNAIDS, and the UN Office on Drugs and Crime. Regional and global estimates of NSP, OST, and HIV testing coverage were also calculated. The protocol was registered on PROSPERO, number CRD42017056558.

Findings: In 2017, of 179 countries with evidence of injecting drug use, some level of NSP services were available in 93 countries, and there were 86 countries with evidence of OST implementation. Data to estimate NSP coverage were available for 57 countries, and for 60 countries to estimate OST coverage. Coverage varied widely between countries, but was most often low according to WHO indicators (<100 needle-syringes distributed per PWID per year; <20 OST recipients per PWID per year). Data on HIV testing were sparser than for NSP and OST, and very few data were available to estimate ART access among PWID living with HIV. Globally, we estimate that there are 33 (uncertainty interval [UI] 21–50) needle-syringes distributed via NSP per PWID annually, and 16 (10–24) OST recipients per 100 PWID. Less than 1% of PWID live in countries with high coverage of both NSP and OST (>200 needle-syringes distributed per PWID and >40 OST recipients per 100 PWID).

Interpretation: Coverage of HIV and HCV prevention interventions for PWID remains poor and is likely to be insufficient to effectively prevent HIV and HCV transmission. Scaling up of interventions for PWID remains a crucial priority for halting the HIV and HCV epidemics.