Adenovirus
Human adenoviruses (HAdVs) are non-enveloped, double-stranded DNA viruses in the family Adenoviridae. Seven species (A–G) and more than 60 genotypes cause human infection. In the United States, from 2014 through 2016, the most commonly reported HAdV types were HAdV type 3 (HAdV-3) and HAdV type 2 (HAdV-2).
Illness tends to occur sporadically and without demonstrated seasonality. Outbreaks of HAdV have been reported globally in communities and in closed or crowded settings, including dormitories, health care settings, and among military recruits. Adenoviruses are relatively resistant to chemical and physical agents and to adverse pH conditions and can live for a long time outside the body.
Adenoviruses most commonly cause respiratory illness. The symptoms can range from the common cold to pneumonia, croup, and bronchitis. Depending on the type, adenoviruses can cause other illnesses such as gastroenteritis, conjunctivitis, cystitis, and less commonly, neurological disease.
Infants and people with weakened immune systems are at high risk for severe complications of adenovirus infection. Some people infected with adenoviruses can have ongoing infections in their tonsils, adenoids, and intestines that do not cause symptoms. They can shed the virus for months or years. Even if a person test positive for adenovirus, it does not necessarily mean that it is causing the current illness. A person can shed the virus for months or years and not have symptoms.
In late 2021, cases of pediatric hepatitis reported in the United Kingdom and the United States. As of October 5, 2022, there have been 368 cases and 13 deaths in 42 states in the US. Six percent of patients have required liver transplantation. The most likely etiology appears to be coinfection with adenovirus subtype F41 (HAdV-F41) and adenovirus associated virus (AAV2).
There is no specific therapy for adenoviruses. However, cidofovir has been used to treat severe adenovirus infections in people with immunocompromised systems. Serious adenovirus infections can only be managed by treating symptoms and complications of the infection.
To prevent nosocomial outbreaks of adenovirus infections, health care providers should strictly follow infection control practices, including contact and droplet precautions.
Adenovirus infections can be identified using antigen detection, polymerase chain reaction assay, virus isolation, and serology. Specimens for PCR include respiratory specimens, cerebrospinal fluid, ocular swabs and stool or rectal swabs. Adenovirus typing is usually done by hemagglutination-inhibition and/or neutralization with type-specific antisera or by molecular methods.
References
Binder AM et al. Human Adenovirus Surveillance – United States, 2003-2016. MMWR Weekly, October 6,2017;66(39)1039-42.
Lion T. Adenovirus infections in immunocompetent and immunocompromised patients. Clin Microbiol Rev 2014;27:441–62.
