Unsafe injections in the developing world and transmission of bloodborne pathogens: a review

Abstract

Unsafe injections are suspected to occur routinely in developing countries. We carried out a literature review to quantify the prevalence of unsafe injections and to assess the disease burden of bloodborne infections attributable to this practice. Quantitative information on injection use and unsafe injections (defined as the reuse of syringe or needle between patients without sterilization) was obtained by reviewing the published literature and unpublished WHO reports. The transmissibility of hepatitis B and C viruses and human immunodeficiency virus (HIV) was estimated using data from studies of needle-stick injuries. Finally, all epidemiological studies that linked unsafe injections and bloodborne infections were evaluated to assess the attributable burden of bloodborne infections. It was estimated that each person in the developing world receives 1.5 injections per year on average. However, institutionalized children, and children and adults who are ill or hospitalized, including those infected with HIV, are often exposed to 10-100 times as many injections. An average of 95% of all injections are therapeutic, the majority of which were judged to be unnecessary. At least 50% of injections were unsafe in 14 of 19 countries (representing five developing world regions) for which data were available. Eighteen studies reported a convincing link between unsafe injections and the transmission of hepatitis B and C, HIV, Ebola and Lassa virus infections and malaria. Five studies attributed 20-80% of all new hepatitis B infections to unsafe injections, while three implicated unsafe injections as a major mode of transmission of hepatitis C. In conclusion, unsafe injections occur routinely in most developing world regions, implying a significant potential for the transmission of any bloodborne pathogen. Unsafe injections currently account for a significant proportion of all new hepatitis B and C infections. This situation needs to be addressed immediately, as a political and policy issue, with responsibilities clearly defined at the global, country and community levels.

PIP: Unsafe injections and the consequent transmission of bloodborne pathogens are suspected to occur routinely in the developing world. This paper presents a review of the literature to determine the prevalence of unsafe injection practices and assess the disease burden of bloodborne infections. Quantitative data on injection usage and unsafe injection practices, such as the reuse of unsterilized syringe or needles between patients, is obtained by reviewing published articles and unpublished reports of the WHO. In addition, the transmissibility of hepatitis B and C viruses and HIV was determined using information from studies of needle-stick injuries. All epidemiological researches that associate injections with bloodborne diseases were examined to assess the attributable burden of bloodborne infections. It was estimated that each person in developing countries receives an average of 1.5 injections per annum. However, institutionalized children, children and adults who are sick or confined in hospitals, often receive 10-100 times as many injections. Of these injections, 95% are therapeutic, a majority of which are unnecessary. At least 50% of injections in 14 of 19 countries were unsafe. Furthermore, 18 studies present convincing evidence on the association of unsafe injection practices and the transmission of bloodborne viruses such as hepatitis B and C, Ebola, Lassa virus infections and malaria. Such practices account for a significant number of hepatitis B and C infections.