For instance, in the United States, despite the potential for illness and death, only 40 per cent of adults receive the flu shot each year. In Canada, the number is even lower. Roughly 34 per cent of the population, receive the flu vaccine each year.
Of course, there are other reasons why people are skeptical about flu shots. However, researchers from the U.S. believe that a painless, vaccine skin patch has the potential of substantially increasing the number of people that get vaccinated.
A Phase I clinical trial conducted by Emory University in collaboration with researchers from the Georgia Institute of Technology has found that influenza vaccination using Band-Aid-like patches with dissolvable microneedles was safe and well-tolerated by study participants, was just as effective in generating immunity against influenza, and was strongly preferred by study participants over vaccination with a hypodermic needle and syringe.
The study was published on June 27 this year in The Lancet.
“Despite the recommendation of universal flu vaccination, influenza continues to be a major cause of illness leading to significant morbidity and mortality,” said first author Nadine Rouphael, M.D., associate professor of medicine (infectious diseases) at Emory University School of Medicine and principal investigator of the clinical trial. “Having the option of a flu vaccine that can be easily and painlessly self-administered could increase coverage and protection by this important vaccine.”
The clinical trial was conducted between June 23 and Sept 25, 2015. The tests involved 100 participants.
The participants were randomly assigned to four groups and received a single dose of inactivated influenza vaccine (fluvirin: 18 μg of haemagglutinin per H1N1 vaccine strain, 17 μg of haemagglutinin per H3N2 vaccine strain, and 15 μg of haemagglutinin per B vaccine strain).
The four groups were:
- Participants receiving microneedle patches
- Participants receiving intramuscular injection,
- Participants receiving placebo by microneedle patch
- Participants self-administering microneedle patch with inactivated influenza vaccine by
“There were no treatment-related serious adverse events, no treatment-related unsolicited grade 3 or higher adverse events, and no new-onset chronic illnesses,” the study summary said.
Local skin reactions to the patches were mostly faint redness and mild itching that lasted two to three days.
Antibody responses generated by the vaccine, as measured through analysis of blood samples, were similar in the groups vaccinated using patches and those receiving an intramuscular injection, and these immune responses were still present after six months. More than 70 percent of patch recipients reported they would prefer patch vaccination over injection or intranasal vaccination for future vaccinations.
No significant difference was seen between the doses of vaccine delivered by the health care workers and the volunteers who self-administered the patches, showing that participants were able to correctly self-administer the patch. After vaccination, imaging of the used patches found that the microneedles had dissolved in the skin, suggesting that the used patches could be safely discarded as non-sharps waste. The vaccines remained potent in the patches without refrigeration for at least one year.
“People have a lot of reasons for not getting flu vaccinations,” said senior co-author Mark Prausnitz, Ph.D., Georgia Tech Regents professor of chemical and biomolecular engineering. “One of the main goals of developing the microneedle patch technology was to make vaccines accessible to more people.”
The vaccine patches have other advantages.
For instance, traditionally, people receiving and influenza vaccine, need to visit a health care professional. The vaccine has to be store in a refrigerator and the needle has to disposed of safely in a special container.
“With the microneedle patch, you could pick it up at the store and take it home, put it on your skin for a few minutes, peel it off and dispose of it safely, because the microneedles have dissolved away. The patches can also be stored outside the refrigerator, so you could even mail them to people,” said Prausnitz.