Comparing population estimates for drug users, the prevalence of blood-borne viruses and the provision of services in one London borough: Evidence of a gap in provision?

Aims: To estimate the size of the drug-using population in Lambeth, an inner city London borough, and the prevalence of blood-borne virus (BBV) infections in the drug-using population. To identify possible shortfalls in service provision for drug users. Methods: Direct and indirect estimates of the drug-using population size using national and local data sources. Prevalence estimates for BBV infections were derived from local survey data. Routine data and a survey of borough services for drug users were compiled. Findings: Based on indirect methods we estimated there were 3117 drug users in Lambeth in 2001-2002 (20 per 1000, 15- to 44-year-olds), of whom 1641 were injecting users (11 per 1000); 1353 were reported as being in drug treatment programmes. BBV prevalence rates: hepatitis B, 37%; hepatitis C, 71%; HIV, 6%. Estimated demand for needle exchange services, in terms of one syringe per injection, and methadone maintenance may be up to double local provision. Conclusions: More accurate and feasible methods are needed for the routine estimation of the population of drug users. Accurate information is needed for service planning.