Recombinant #vaccine: protecting animals with viruses
Traditional vaccines work by injecting a weakened or dead version of a disease into a human or animal. Antibodies are produced that can then attack the real disease should it be contracted later. Booster shots are sometimes required to keep antibodies ready to ward of any new attack.
Recombinant vaccines, on the other hand, use viruses to deliver disease protection. A virus is encoded with the protein from another virus. When it enters the host and multiplies, antibodies are produced for both the encoded disease as well as the carrier virus. For example, a virus for fowl pox could express antigens for avian flu, protecting a chicken or turkey from both diseases.
Recombinant vaccines do not require booster shots, and limit the vaccine-related symptoms of traditional shots. Some vaccines can cause mild symptoms of the disease it helps prevent, which can make it difficult to determine which animals have a disease and which are only reacting to the vaccine. Some recombinant vaccines take time to grant full immunity, so traditional vaccines can be used to supplement recombinant vaccines in young animals.