Flu jabs could be rendered obsolete by a skin patch delivering vaccine painlessly through scores of tiny needles.
Scientists believe the patch, successfully tested on mice, could revolutionise pandemic control by allowing self-vaccination as no medical training is required.
After it is applied to the skin, the ‘microneedles’ — each measuring just over half-a-millimetre — deliver the vaccine and simply dissolve away. All that remains is a water-soluble backing that can safely be discarded.
Scientists in the US designed a 100-needle patch that was tested for its ability to penetrate pig skin, which is about the same thickness as its human counterpart.
They then experimented to see how effectively the patch could deliver flu vaccine in mice.
A group received hypodermic needle flu jabs, while others were treated with patches that were either loaded with vaccine or empty.
Three months later mice vaccinated with the microneedles were found to be mounting a stronger immune response than those injected by syringe. They were better able to clear the flu virus from their lungs than animals given the traditional flu jab.
Professor Mark Prausnitz, from the Georgia Institute of Technology in Atlanta, who led the study, reported yesterday in the journal Nature Medicine: “We have shown that a dissolving microneedle patch can vaccinate against influenza at least as well, and probably better than, a traditional hypodermic needle.”
The arrays are made from a plastic-like polymer that is known to be safe for use in the body.
Freeze-dried vaccine was mixed into the material in tiny moulds.
The patch could aid mass-immunisation in poor parts of the world, where re-use of hypodermic needles leads to the spread of infections such as HIV.
“We envision people getting the patch in the mail or at a pharmacy and then self-administering it at home,” said Dr Sean Sullivan, another member of the team.
While the study focused on flu, the technique could be useful for other vaccines, say the scientists.
Before being made generally available, the patch will have to undergo patient trials.