Adenoviruses are double-stranded DNA viruses of animals. The prefix adeno comes from the Greek word meaning "gland," reflecting the first isolation of a virus of this type from human adenoid tissue over a half a century ago. Adenoviruses have been since isolated from many animals, from fish to mammals. Some human and animal adenoviruses can cause disease and even death, but most are not pathogenic in healthy individuals.
Adenoviruses have become one of the most popular vector systems for virus-based gene therapy and vaccination and have potential and have potential as antitumor tools.1
By tradition, adenoviruses have been classified by their hemagglutination (clumping of red blood cells caused by the presence of a virus) and oncogenic (cancer-causing) properties. Adenoviruses belonging to subgenus A are highly oncogenic and induce tumors in newborn hamsters within a few months.
The human adenoviruses are now classified into six subgenera, A to F, containing 49 serotypes.
The non-human adenoviruses are currently divided into two genera: Mastadenovirus (mammalian adenoviruses) and Aviadenovirus. Tests indicate multiple serotypes exist in most animal species. Currently there are 2 equine, 9 bovine, 4 porcine (pig), 6 ovine (sheep), 2 caprine (goat and antelope), 2 canine, 11 chicken, 4 turkey, 3 goose, 2 mice, and 25 simian serotypes of adenovirus. Adenoviruses have also been isolated from quail, pheasants, opossum, rabbits, tree shrews, guinea pigs, rats, and sea lions. They are usually isolated from the upper respiratory tract, conjunctiva, gastrointestinal tract, and feces. Most of these adenoviruses do not produce signs of disease, but pneumonia, conjunctivitis, diarrhea, and hepatitis are frequently observed in animals infected with adenoviruses.2
Diseases in domestic mammals caused by adenoviruses include respiratory or enteric disease in cattle Bos taurus caused by bovine adenovirus 1-6; in sheep Ovis aries caused by ovine adenoviruses 1-6; and hepatitis in dogs Canis familiaris caused by canine adenovirus type 1 (CAV-1).
Some adnoviruses that commonly infect domestic animals can also infect wild animals. For example, infectious canine hepatitis virus of dogs also infects wild members of the Canidae, including coyotes Canis latrans and wolves Canis lupus. Important nondomestic mammalian adenovirus diseases that can manifest as epidemics include fox encephalitis (sometimes called fox distemper) caused by CAV-1, and the recently described adenovirus hemorrhagic disease of deer Odocoileus spp.3