Vaccines can be delivered through the skin using ultrasound. This method doesn’t damage the skin and eliminates the need for painful needles. To create a needle-free vaccine, Darcy Dunn-Lawless at the University of Oxford and his colleagues mixed vaccine molecules with tiny, cup-shaped proteins. They then applied liquid mixture to the skin of mice and exposed it to ultrasound – like that used for sonograms – for about a minute and a half.
It’s certainly less time effective if administering vaccines to large populations at once, but the increased antibody generation could absolutely make it worth it. Don’t know much about these things, but could mean the difference between two jabs and one 1.5 minute appointment.