PATH has collaborated with developers and manufacturers to further evaluate disposable-syringe jet injector (DSJI) designs and conduct clinical testing. At the same time, we are compiling evidence that demonstrates the jet injector will be cost-effective and practical in the developing-country context. We are also developing strategies for introducing the injectors into developing-country immunization programs.

Conduct design research in the field demonstrating acceptability of DSJIs and advancing the potential of DSJIs appropriate for developing-country use. Early feedback on critical design features from health care workers who may use DSJIs has helped to shape and refine the design specifications of an ideal product. We conducted field assessments of injector prototypes in South Africa and Tanzania in 2004 and in Brazil, India, and China in 2006, making important adjustments in response to the feedback we received each time. Follow-up assessments occurred in Brazil in 2008 and 2009. Throughout the field assessments, we were heartened to find that health care workers were highly receptive to needle-free injection and immediately recognized the safety benefits.

Demonstrate effectiveness and acceptability testing through clinical trials. PATH is currently evaluating DSJI delivery of measles-mumps-rubella (MMR) vaccine compared to traditional needle and syringe among infants in Brazil. Later studies include trials with yellow fever vaccine; Diphtheria, tetanus, pertussis, Haemophilus influenza type B, and hepatitis B (DTP-Hib-HepB) vaccine; and others.

Explore the clinical feasibility of intradermal vaccine delivery. PATH also supports clinical research using DSJIs to deliver reduced doses of certain vaccines intradermally. This research involves collaboration with globally recognized vaccine manufacturers and other global public health stakeholders, such as the World Health Organization (WHO) and the United States Centers for Disease Control and Prevention (CDC). Reduced dosage is appealing to immunization programs because it has the potential to simultaneously increase vaccine availability—thereby increasing coverage for vaccines in short supply—and decrease costs associated with delivery. It may also help to optimize the capacity for the vaccine cold chain. DSJIs could provide an accurate, reliable, needle-free means of administering these vaccines, making this method more appropriate for use in the developing world.

Model the cost-effectiveness of DSJIs to developing-country immunization programs. In addition to the clinical trials, the project work will also include an operational study in Brazil to help determine the commercial and programmatic feasibility of introducing DSJIs not only in Brazil but also in other developing- and emerging-economy markets.

Advance the potential of DSJIs appropriate for developing-country use. By combining scientific rigor with careful economic analysis and close collaboration with in-country partners, PATH is developing a detailed case study for how and where DSJIs could be introduced to the populations we serve. We will advocate to the global health community, in a company-neutral manner, for adoption of the technology and for further research in the field of alternative vaccine delivery technologies.

PATH has worked cooperatively with WHO and DSJI manufacturers to establish a Performance, Quality, and Safety standard for the technology class to facilitate procurement of the DSJI device for developing-country immunization programs. More information about the standard is available on the immunization standards page of the WHO website.