vaccines and other medicines has helped save countless lives and extended life expectancy, the technology has essentially remained the same for 160 years.
Now a scientist has invented a tiny square patch (smaller than a postage stamp) that can deliver a dose of vaccine in dry form to immune cells just under the outer layer of skin. Inventor Mark Kendall claims his new Nanopatch device is more efficient at delivering vaccines, avoids problems with dirty needles, overcomes vaccine storage issues and, for those with a fear of needles (20% of the population are estimated to have needle phobia), it will come as a welcome relief.
Biomedical engineer Kendall’s approach involves an array of thousands of vaccine-coated microprojections that perforate the outer layers of the skin when applied with an applicator device. The tips of the microprojections are coated with a dry vaccine material and release it directly to the “large numbers of key immune cells immediately below the skin surface”.
Professor Kendall says animal research shows that a 450ng dose of an influenza vaccine was far more effective delivered through the patch than 600ng of the same vaccine delivered via a needle. This is because conventional needles deliver vaccines into muscle, missing the immune sweet spot of the skin, Kendall claims.
Furthermore, because less vaccine is needed for delivery via the new technology, it could make an expensive vaccine more viable to distribute in the developing world. Professor Kendall says that his delivery technique requires only up to one hundredth of a traditional dose, meaning that a $10 shot should only cost 10 cents.
One particular issue with vaccines is the need to refrigerate the liquid from manufacture through to inoculation for them to remain effective. Half the vaccines used in Africa aren’t effective because this so-called ‘cold chain’ is broken at some point, according to the World Health Organisation. Kendall claims that because his patch is coated with a dry vaccine, it won’t need refrigeration.
He reveals that Nanopatch is beginning a pilot test in Papa New Guinea, a country the same size as France. Although it has the highest rate of HPV (human papillomavirus), there are only 800 fridges available in the country to store vaccines under appropriate conditions. Kendall hopes the Nanopatch can help distribute this vaccine there.
Other medical experts welcomed the news, but are cautious about whether the technology is suitable for all patients. Interviewed by the BBC, Dr Diane Williamson of the British Society for Immunology, said: “This approach holds out hope for easy and large-scale vaccination, as it targets a type of immune cell, called the Langerhans cell that is abundant in the skin. These cells avidly take up the vaccine and are able to kick-start the immune response.
She added: “There may be issues of tolerability of the patch in some people. However, if these issues can be overcome, the approach does hold out the potential to dispense with conventional needle-based ‘intra-muscular’delivery."
In the meantime, until the technology is perfected, it is important that the highest standards are maintained using conventional procedures, for instance to avoid needle-stick injuries, which cause 1.3 million early deaths a year. Here at 3B Scientific, we offer a comprehensive range of injection trainers for a broad range of infant and adult procedures.