In the field of immunology and genomic research, various viral vectors play a crucial role in vaccine development. Commonly utilized vectors include Adenovirus, Adeno-associated virus, Herpes simplex virus, measles virus, and retrovirus vectors. The development process typically integrates a combination of in vitro, ex vivo, and in vivo approaches. According to a study accessible on PubMed, "Adenoviruses are efficacious vaccine vectors against diseases in which traditional vaccine development strategies have proven ineffective. Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4847555/