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The intradermal site is rich in dendritic cells and, consequently, an excellent site for inducing immune responses. The best current example being the intradermal influenza vaccine.
So one could reasonably argue that the site would be excellent with the exception of oral vaccines (like rotavirus or oral polio) or live attenuated viral vaccines (like measles, mumps, rubella, or varicella). Indeed, the site could be of great value for diphtheria, pertussis, tetanus, Hib, pneumococcus, hepatitis B, HPV, or inactivated polio vaccines. The difficulty of course is that the path to licensure of a new product going up against existing vaccines is steep.