A number of other vaccines have been considered for ID delivery. Research has shown that a reduced ID dose of vaccines for diphtheria-tetanus-pertussis, tetanus toxoid, and tick-borne encephalitis can generate a comparable immune response to the standard dose and way of injection (Stanfield et al. 1972; Zoulek et al. 1984; Zoulek et al. 1986; Dimache et al. 1990 ). ID delivery is also under investigation for a number of vaccines in development, including vaccines for tuberculosis, enterotoxigenic E. coli, and pandemic influenza, as well as DNA vaccines.