The 1967 Needle-Free Injection

In this fascinating 1967 archival footage, health workers use a needle-free jet injector to rapidly vaccinate crowds during a mass immunization campaign. The device delivers the vaccine through a high-pressure, narrow stream of liquid that penetrates the skin without a needle—allowing hundreds of people to be vaccinated in minutes. While incredibly efficient, jet injectors never became widely popular because later studies found they could sometimes transfer blood between patients, raising concerns about cross-contamination and the spread of blood-borne diseases like hepatitis. By the late 20th century, most programs returned to traditional single-use needles for safety.

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