Advances in the intradermal vaccination

Vaccination is the most effective solution to fighting against infectious diseases. The method of inoculation is the key factor for successful immunization. Skin is the ideal inoculation site for vaccines because of the huge amounts of antigen-presenting cells especially Langerhans cells. However, conventional syringes have many limitations in intradermal inoculation, such as the high difficulty in operation, poor patient compliance, and potential contamination risks to the environment. In recent years, with the in-depth study of transdermal drug delivery systems, a series of new intradermal inoculation techniques and devices have also been vigorously developed. In this review, we summarize the current methods and status of vaccination, introduce the advantages of intradermal vaccination, and focus on new technologies such as microneedle, laser, and gene gun, as well as their application research progress in intradermal vaccination.