Abstract
Conventional vaccination is performed mainly by injection, which has several inherent problems: pain, the need for trained personnel, associated needle-related diseases or injuries, and storage or transport issues. In some areas, vaccine coverage against infection is low due to failure in follow-up as well as a lack of trained medical personnel and facilities. Thus, the development of needle-free, easy-to-use, and low-invasive vaccination methods is an urgent task. With its advantages that overcome the inherent problems of vaccination by injection, transcutaneous immunization is now attracting attention as an alternative vaccination route. Herein, we provide an outline of recent trends in the development of transcutaneous vaccine formulations utilizing the microneedle technology.
