Adenovirus Overview

Adenovirus Characteristics

• Medium-sized, non-enveloped, double-stranded DNA viruses
• Share a common complement fixing antigen
• Infect both humans and animals
• Most infections are asymptomatic, especially in children
• Icosahedral shape, approximately 80-110 mm in diameter, with 252 capsomeres
• Fibre projects from each of 12 vertices, resembling a space ship

Classification

• Family: Adenoviridae
• Genus: Mastadenovirus (adenovirus of mammals)
• Species: Human adenovirus
• At least 52 distinct antigenic types isolated from humans, many more from animals
• Human adenovirus divided into seven groups (A-G)

Disease Associations

• Transmission: Contact with droplets from the nose and throat of an infected person (e.g., during coughing or sneezing) or by touching hands/an object
• Symptoms: Cold-like symptoms, including sore throat, sneezing, runny nose, cough, headache, chills, or symptoms of croup or bronchitis
• Complications: Ear infections, pneumonia, or meningitis (inflammation of the brain and spinal cord)
• Lasts: 3-5 days, but serious infections can last for weeks

Laboratory Diagnosis

• Specimen sources: Throat, eye, urine, feces
• Isolation of virus: Inoculation into cell cultures (human embryonic kidney, HeLa, HeP2), with characteristic cytopathic effects (CPE) of cell rounding and aggregation into grape-like clusters
• Other tests: Hemadsorption (HA), Neutralization, Complement Fixation (CF) Serology, and Electron Microscopy (for stool)

Treatment and Prevention

• Potential targets: AdV DNA polymerase, AdV Cysteine protease, and receptors for binding host cells
• Antivirals in use: Ribavirin, Cidofovir, Ganciclovir, and Vidarabine
• Prevention: Vaccines available for adenovirus serotypes 4 and 7 (preventing ARD among military recruits), strict attention to good infection-control practices