Edible vaccines also have multiple disadvantages compared to traditional vaccines. Since edible vaccines are still in their infancy, there are still many unknowns left to discover. The adequate dosage amount and how long it lasts is still undetermined. The dosage varies due to many factors including: the plant generation, the individual plant, the protein content, the ripeness of the fruit and how much of it is eaten. The dosage also varies due to the difficulty in standardizing the concentration of the antigen in the plant tissue; it can be tedious to produce both consistently and large scale. The antigen concentration can also vary significantly between individual fruits on a plant, individual plants, and between plant generations. Low doses result in the consumption of less antibodies but a high dose results in establishing an oral and immune tolerance to the vaccine proteins. The logistics of controlling dosage, quality, and consistency still need to be determined and verified.
