Jet injectors use high pressure rather than needles to deliver vaccine. Photo: PATH/Patrick McKern.
A safe, efficient way to get vaccines and essential medicines to children
Injections without needles? It may sound too good to be true, but needle-free innovations have the potential to make it safer and easier for health workers in low-resource settings to give vaccines and essential medicines—and for children to receive them.
“Jet injector” technologies use high pressure rather than needles to deliver vaccines and drugs as a fine pressurized stream of fluid that penetrates through the skin and into tissue. Jet injectors were first introduced in the 1940s and used in mass vaccination campaigns against such diseases as smallpox, polio, influenza, and measles.
PATH is helping to advance a new generation of jet injectors, known as disposable-syringe jet injectors (DSJIs), that have been redesigned with new features that make them safer and more effective.
DSJIs offer a way to overcome the risks associated with needle-based injections, especially in developing countries where injection safety and medical waste challenges persist. Reuse of contaminated needles and syringes, needlestick injuries, and improper disposal can spread infection and diseases, such as HIV and hepatitis, to health care workers, patients, and communities. By eliminating the need for needles, DSJIs go a long way toward protecting both patients and health workers.
In addition, unlike older, multi-use nozzle models, the disposable syringe that comes into contact with a person is sterile and for single use only, eliminating risk of cross-contamination.
DSJIs have another benefit: they can reliably deliver vaccine and medicines into the upper intradermal layers of the skin as well as into the fat and muscle tissue. Intradermal delivery of some vaccines can achieve similar clinical results as standard delivery depth injections while using much smaller dose volumes. DSJIs have the potential to increase efficiency and save money through the use of intradermal delivery, allowing lifesaving vaccines to go much further in countries where they are expensive or in short supply.
Changing the landscape of immunization
PATH has a long history of partnering with device developers, ministries of health, the World Health Organization (WHO), and others to advance the research, development, and use of DSJIs. Our work ranges from engineering and health care worker assessments of DSJI prototypes, which help ensure that devices are appropriate and acceptable in low-resource settings, to clinical research comparing DSJIs to traditional needles and syringes for the delivery of immunization program vaccines such as those against diphtheria, pertussis, tetanus, hepatitis B, tuberculosis, polio, measles, mumps, and rubella.
We also provide technical support to help manufacturers and others navigate the regulatory approval process. These efforts led to the first WHO prequalification of a DSJI device. This critical step makes it easier for multilateral agencies and countries to purchase DSJIs and to include them in national immunization programs.
With the ability of DSJI’s to provide immunizations without needles and their potential to use less vaccine, these innovations could help children worldwide receive the protection from a host of diseases, giving them a better chance to lead healthy, productive lives.