Purdue University

What if getting a flu vaccine no longer involved getting a shot?

Researchers at Georgia State University have spent the past few years working on a microneedle patch that dissolves into the skin for patients to easily and painlessly self-administer vaccines. Now, they've developed a flu vaccine using the system that, when tested on mice, proved to be 100 percent effective more than a year after the mice were vaccinated.

As they report in the September 2013 issue of the journal Clinical and Vaccine Immunology, the influenza vaccine uses dry virus-like particles (VLP) instead of a liquid with the dead or attenuated virus. The VLPs coat the micronneedle patch alongside a stabilizing agent, so that the patches won't necessarily need to be refrigerated.

At just seven-tenths of a millimeter in length, the microneedles do away with the pain some experience when getting vaccines via hypodermic needles. What's more, the precise delivery method afforded by such tiny needles requires a smaller dose, which in turn further reduces the already low risk of side effects.

The researchers previously tested the VLP-coated microneedles to measure short-term protection, and found that the approach actually offers greater protection than conventional intramuscular immunization. Now they confirm that 14 months after immunization, the mice were 100 percent protected. You just don't get better numbers than that.

Sang-Moo Kang, a researcher at George State, said he envisions patients some day being able to self-administer the vaccine easily and painlessly and with fewer side effects. Perhaps then the seasonal flu vaccination rate would rise above the 43 percent reported in the 2010-2011 season.