RESUMEN
BACKGROUND: Disposable-syringe jet injectors (DSJIs) have the potential to deliver vaccines safely and affordably to millions of children around the world. We estimated the incremental costs of transitioning from needles and syringes to delivering childhood vaccines with DSJIs in Brazil, India, and South Africa. METHODS: Two scenarios were assessed: (1) DSJI delivery of all vaccines at current dose and depth; (2) a change to intradermal (ID) delivery with DSJIs for hepatitis B and yellow fever vaccines, while the other vaccines are delivered by DSJIs at current dose and depth. The main advantage of ID delivery is that only a small fraction of the standard dose may be needed to obtain an immune response similar to that of subcutaneous or intramuscular injection. Cost categories included were vaccines, injection equipment, waste management, and vaccine transport. Some delivery cost items, such as training and personnel were excluded as were treatment cost savings caused by a reduction in diseases transmitted due to unsafe injections. RESULTS: In the standard dose and depth scenario, the incremental costs of introducing DSJIs per fully vaccinated child amount to US$ 0.57 in Brazil, US$ 0.65 in India and US$ 1.24 in South Africa. In the ID scenario, there are cost savings of US$ 0.11 per child in Brazil, and added costs of US$ 0.45 and US$ 0.76 per child in India and South Africa, respectively. The most important incremental cost item is jet injector disposable syringes. CONCLUSION: The incremental costs should be evaluated against other vaccine delivery technologies that can deliver the same benefits to patients, health care workers, and the community. DSJIs deserve consideration by global and national decision-makers as a means to expand access to ID delivery and to enhance safety at marginal additional cost.