Evidence and information for national injection safety policies

The adverse consequences of poor injection practices have been reported for a few decades. However, key elements of evidence and information were lacking to allow decision-makers to formulate policies for the safe and appropriate use of injections. We conducted studies to (1) estimate the frequency of injection use and of poor injection practices, (2) estimate the consequences of poor injection practices in terms of death and disability, (3) formulate best infection control practices for intradermal, subcutaneous and intramuscular injections, (4) quantify the effectiveness of interventions to reduce unnecessary and unsafe use of injections and (5) estimate the cost-effectiveness of national policies for the safe and appropriate use of injections. WHO's Global Burden of Disease project defined 14 regions based on geography and mortality patterns. The analysis excluded four regions (predominantly affluent, developed nations) where reuse of injection equipment in the absence of sterilization was assumed to be negligible. To estimate the frequency of poor injection practices in the year 2000, data sources included published studies and unpublished WHO reports. Studies were reviewed using a standardized decision-making algorithm based upon the quality of the data to generate region-specific estimates of the annual number of injections per person and of the proportion of injections reused in the absence of sterilization. To estimate the consequences of unsafe injections in the year 2000 in terms of death and disability for 2000-2030 as part of the 2000 update of WHO’s Global Burden of Disease study, we modelled the fraction of new injection-associated HBV, HCV and HIV infections on the basis of the annual number of injections, the proportion of injections administered with reused equipment, the probability of transmission following percutaneous exposure, the prevalence of active infection, the prevalence of immunity and the total incidence. Infections in 2000 were converted into disability-adjusted life years (DALYs) in 2000-2030 using natural history parameters, background mortality, duration of disease, disability weights, age weights and a 3% discount rate. A guideline development group summarized evidence-based best practices to prevent injectionassociated infections in resource-limited settings. The development process included (1) a breakdown of the WHO reference injection safety definition into a list of potentially critical steps, (2) a review of the literature for each of these potentially critical steps, (3) the formulation of best practices and (4) the submission of the draft document to peer review. To estimate the effectiveness of interventions to reduce the unnecessary and unsafe use of injections, we searched electronic databases. In addition, we reviewed WHO reports and unpublished assessments made available to WHO. We selected studies that contained quantitative and qualitative information on the effect of interventions and that provided information on study design, type of interventions, targeted participants and targeted behaviours. To estimate the cost-effectiveness of national policies for the safe and appropriate use of injections, the consequences in 2000-2030 of a "do nothing" scenario for the year 2000 (as modelled for the Global Burden of Disease study) were compared to a set of counterfactual scenarios incorporating the health gains of effective interventions. Resources needed to implement effective interventions were costed for each sub-region and expressed in international dollars (I$). Four regions in the Global Burden of Disease study where reuse of injection equipment in the absence of sterilization was negligible were excluded from the analysis. In the 10 other regions, the annual ratio of injections per person was 3.4 (Range: 1.7 - 11.3) for a total of 16.7 thousand million injections received. Of these, 39.3% (Range: 1.2% - 75.0%) were administered with equipment reused in the absence of sterilization. Reuse was highest in the South East Asia region “D” (seven countries, mostly located in South Asia), the Eastern Mediterranean region “D” (nine countries, mostly located in the Middle East crescent) and the Western Pacific region “B” (22 countries) which together accounted for 88.4% of the 6.5 thousand million injections given in the year 2000 with equipment reused in the absence of sterilization. In 2000, contaminated injections caused an estimated 21 million HBV infections, two million HCV infections and 260 000 HIV infections, accounting for 32%, 40% and 5% respectively of new infections for a burden of 9 177 679 DALYs between 2000 and 2030. Eliminating unnecessary injections is the highest priority to prevent injection-associated infections. However, when intradermal, subcutaneous or intramuscular injections are medically indicated, best infection control practices include (1) the use of sterile injection equipment, (2) the prevention of contamination of injection equipment and medication, (3) the prevention of needle-stick injuries to the provider and (4) the prevention of access to used needles. We identified twenty-one articles, abstracts, unpublished reports and assessments containing information on the effectiveness of interventions aiming at reducing injection use (n=19) and at decreasing the unsafe use of injections (n=5). Studies showed a reduction in injection use ranging from 1% to 53% (gain over control groups: 3%-27%). Interventions aiming at reducing the reuse of injection equipment in the absence of sterilization reported an absolute decrease of 30%-82% in the intervention groups (relative decrease: 40-100%). Interventions implemented in the year 2000 for the safe (provision of single use syringes, assumed effectiveness: 95%) and appropriate use (patients-providers interactional group discussions, assumed effectiveness: 30%) of injections could reduce the burden of injection-associated infections by as much as 96.5% (8.86 million DALYs) for an average yearly cost of I$ million 905 (average cost-effectiveness per DALY averted: I$102, range by region: 14-2 293). In 2000, in developing and transitional countries, 16 thousand million injections were administered for a ratio of 3.4 injections per person. More than a third of all these injections were administered with injection equipment reused in the absence of sterilization, accounting for a substantial burden of infection with bloodborne pathogens. Best infection control practices could make injections safer for the recipient, the health care workers and the community, all the more as effective interventions are available to reduce injection use and to achieve a safe use of injections. These interventions can also be considered very cost-effective on the basis of a cost per DALY averted that is below one year of average per capita income. Remaining areas of uncertainty include (1) the formulation of routine methods to describe injection use and to quantify needs of injection equipment, (2) the description of unsafe practices in greater detail to prevent all opportunities of transmission, (3) the need to generate better estimates of the proportion of HIV infections that may be attributed to unsafe health care injections, (4) the identification of the role of engineered technologies in policies to achieve injection safety, (5) the recovery of experience in the scaling-up of successful interventions and (6) the assessment of the cost-effectiveness of scaled-up national interventions.