NOTE- Adenovirus was recently detected in free-ranging bears in Maryland (see abstract below). Scientific studies to determine if ticks on bears could contract the virus and transmit it to humans has not been explored.

Adenovirus infections most commonly cause illness of the respiratory system; however, depending on the infecting serotype, they may also cause various other illnesses and presentations.

Several adenoviruses, especially adenovirus serotype 36 (Adv36), have been shown to cause obesity in animals, and are associated with human obesity.[4][5]

DIAGNOSIS- Antigen detection, polymerase chain reaction assay, virus isolation, and serology can be used to identify adenovirus infections. Adenovirus typing is usually accomplished by hemagglutination-inhibition and/or neutralization with type-specific antisera. Since adenovirus can be excreted for prolonged periods, the presence of virus does not necessarily mean it is associated with disease.

SYMPTOMS- Apart from respiratory involvement, illnesses and presentations of adenovirus include gastroenteritis,[1] conjunctivitis, cystitis, and rash illness. Symptoms of respiratory illness caused by adenovirus infection range from the common cold syndrome to pneumonia, croup, andbronchitis. Patients with compromised immune systems are especially susceptible to severe complications of adenovirus infection. Acute respiratory disease (ARD), first recognized among military recruits during World War II, can be caused by adenovirus infections during conditions of crowding and stress.

TREATMENT- Most infections are mild and require no therapy or only symptomatic treatment. Because there is no virus-specific therapy, serious adenovirus illness can be managed only by treating symptoms and complications of the infection. Deaths are exceedingly rare but have been reported.[6]

More Information at WIKI

Additional Information

Adenoviridae infect a variety of vertebrates including mammals, fish, birds and reptiles [1]. More than 50 human adenoviruses (HAd) serotypes have been identified. A handful of these are extensively studied because of their tendency to induce respiratory, ocular, and enteric infections in immunocompetent individuals as well as morbidity and mortality in severely immunodeficient patients

Due to multiple infections during childhood, most of us (>85%) possess relatively high circulating Abs against several HAd serotypes [8,63]. In addition, transient depletion of antiviral antibodies from a patient could put them at risk for HAd disease from latent HAds [67].

From- An Update on Canine Adenovirus Type 2 and Its Vectors Thierry Bru 1,2,3, Sara Salinas 1,2,3 and Eric J. Kremer 1,2,3,*

J Wildl Dis. 2014 Jul 30. [Epub ahead of print]

Serosurvey For Selected Pathogens In Free-Ranging American Black Bears (Ursus americanus) In Maryland, USA.

Bronson E1, Spiker H, Driscoll CP.

Author information

11 Maryland Zoo in Baltimore, 1876 Mansion House Drive, Baltimore, Maryland 21217, USA.


Abstract American black bears (Ursus americanus) in Maryland, USA, live in forested areas in close proximity to humans and their domestic pets. From 1999 to 2011, we collected 84 serum samples from 63 black bears (18 males; 45 females) in five Marylandcounties and tested them for exposure to infectious, including zoonotic, pathogens.

A large portion of the bears had antibody to canine distemper virus and Toxoplasma gondii, many at high titers. Prevalences of antibodies to zoonotic agents such as rabies virus and to infectious agents of carnivores including canine adenovirus and canine parvovirus were lower.

Bears also had antibodies to vector-borne pathogens common to bears and humans such as West Nile virus, Borrelia burgdorferi, Rickettsia rickettsiae, and Anaplasma phagocytophilum. Antibodies were detected to Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. We did not detect antibodies to Brucella canis or Ehrlichia canis.

Although this population of Maryland black bears demonstrated exposure to multiple pathogens of concern for humans and domesticated animals, the low levels of clinical disease in this and other free-ranging black bear populations indicate the black bear is likely a spillover host for the majority of pathogens studied.

Nevertheless, bear populations living at the human-domestic-wildlife interface with increasing human and domestic animal exposure should continue to be monitored because this population likely serves as a useful sentinel of ecosystem health.


American black bear; Maryland; Ursus americanus; disease; serosurvey

PMID: 25075540

[PubMed - as supplied by publisher]

Last Updated- March 2019

Lucy Barnes