Autopsy cases who had received Abeta vaccine showed clearance of senile plaques, and beneficial effect was shown in patients who had high antibody titers to amyloid plaques. Thus, vaccination is widely accepted as promising therapy for Alzheimer disease. Since active immunization induced autoimmune-like meningoencephalitis, pharmaceutical companies are interested in passive immunization using monoclonal antibodies to Abeta. However, due to immunization burden and economical issues, safe active immunization is still attractive. We developed oral or nasal Abeta vaccine using viral vectors and Abeta cDNA with a signal peptide. These vaccine reduced amyloid burden and improved cognitive functions in mice. We believe this vaccine is useful for prevention and treatment of Alzheimer disease.