Adenoviridae

Adenoviridae is a family of viruses whose genetic material is linear double-stranded DNA. These viruses lack an outer envelope; instead they have a protein shell with a geometric structure, which makes them resistant to environmental conditions and certain disinfectants. They are found in humans, mammals, birds, and insects.

Human adenoviruses in this family commonly cause upper respiratory infections, conjunctivitis, sore throat, and gastrointestinal disease. Most cases are self-limiting, but in immunocompromised individuals—such as transplant recipients—infections can become severe.

Structure and morphology

The viral capsid has an icosahedral structure with 20 faces. Protruding from the vertices are protein fibers called fibers, which attach to receptors on the host cell. The DNA genome is contained within the capsid and ranges from approximately 26 to 48 kilobases in length, depending on the type.

Divisions of the family

The family is subdivided into several genera, including Mastadenovirus (mammals, which includes human types), Aviadenovirus (birds), Atadenovirus, and Siadenovirus. Human adenoviruses are further classified into species groups (A through G) and numerous serotypes.

Transmission and prevention

Transmission occurs through respiratory droplets and secretions, direct hand contact, contaminated water that is not properly treated, and fecal contamination. The most effective prevention measures are handwashing, cleaning of medical equipment, and isolation when infection is detected in crowded settings such as hospitals and schools.

Scientific applications

Adenoviruses are widely used in molecular biology research as vectors to introduce genetic material into cells. Modified, non-replicating versions have been employed in some vaccines and gene therapy studies. This work has provided a foundation for vaccine development in recent years.