Fowl Adenovirus 1

Virus: Fowl Adenovirus 1

Structure: Non-enveloped

Genome: Double-stranded DNA

Family: Adenoviridae

Primary Host: Birds

Diseases caused: Inclusion body hepatitis, hepatitis hydropericardium syndrome (HS), and adenoviral gizzard erosion

Symptoms:  asymptomatic or may display respiratory issues, ruffled feathers, huddling, reduced egg production/low hatchability, depression, anorexia, growth delay, diarrhea, enteritis with varying degrees of mortality

Potential complications: Have a potential immunosuppressive capability leaving birds vulnerable to secondary infections.

Transmission mode: Transmitted primarily via direct contact with feces or fluid from infected birds and humans or from contaminated fomites. Transmission from parent to offspring may occur.

Sites of Community Outbreaks: Commercial poultry farms, poultry-processing plants

Importance of Fowl Adenovirus 1:

Fowl Adenovirus 1 (FAdVs) is a non-enveloped member of the Adenoviridae family, and predominantly affects poultry such as chickens, house sparrows, turkeys, ducks, geese, guinea fowls.

Typically, birds infected with Fowl Adenovirus present mild or no symptoms, but different subtypes are associated with clinical conditions such as inclusion body hepatitis, hepatitis hydropericardium syndrome, ulceration syndrome, and adenoviral gizzard erosion. Additionally, symptoms of Fowl Adenovirus 1 infection can vary depending on age, breed, health, and organ impacted by the virus.

FadV is primarily a concern in commercial poultry farms and poultry-processing plants as an outbreak can result in substantial economic losses. Especially problematic is that the virus can spread easily by asymptomatic chickens. Infections in older breeder chickens are generally mild if they present any symptoms at all. Infected breeder chickens may show decreased egg production with low hatchability or may pass the virus to offspring (broiler chickens). Broiler chicken flocks raised for meat production (aged between 3 -4 weeks) are particularly susceptible to infection and generally have a higher mortality rate.

The global chicken and egg trade has the potential to increase the chance of introducing Fowl Adenovirus 1 to other countries.

THE IMPORTANCE OF DISINFECTION: SURVIVAL OF ADENOVIRUS ON SURFACES AND TRANSMISSION POTENTIAL VIA FOMITES

FadV is typically transmitted via direct contact with feces or fluid from infected birds. However, the virus can also be transmitted by coming in contact with contaminated transport vehicles, personnel, and equipment.

Fowl Adenovirus 1 is heat resistant and can tolerate changes in pH between 3-9, thus allowing it to remain infectious in the environment for an extended period of time and making it difficult to destroy. Additionally, it has shown to be resistant to certain organic solvents such as ether, chloroform, sodium deoxycholate, phenol, trypsin, and certain acids. While this virus is non-enveloped and is generally hardier than other virus types, it has shown to be susceptible to disinfectants such as calcium hydroxide, chlorine, and glutaraldehyde.

References

Cizmecigil, U. Y., Umar, S., Yilmaz, A., Bayraktar, E., Turan, N., Tali, B., … & Yilmaz, H. (2020). Characterisation of fowl adenovirus (FAdV-8b) strain concerning the geographic analysis and pathological lesions associated with inclusion body hepatitis in broiler flocks in Turkey. Journal of veterinary research, 64(2), 231-237.

Inoue, D., Hayashima, A., Tanaka, T., Ninomiya, N., Tonogawa, T., Nakazato, S., & Mase, M. (2020). Virucidal effect of commercial disinfectants on fowl adenovirus serotype 1 strains causing chicken gizzard erosion in Japan. Journal of Applied Poultry Research, 29(2), 383-390.

Norina, L., Norsharina, A., Nurnadiah, A. H., Redzuan, I., Ardy, A., & Nor-Ismaliza, I. (2016). Avian adenovirus isolated from broiler affected with inclusion body hepatitis. Malaysian J Vet Res, 7, 121-126.

Tsiouris V, Mantzios T, Kiskinis K, Guérin J-L, Croville G, Brellou GD, Apostolopoulou EP, Petridou EJ, Georgopoulou I. First Detection and Identification of FAdV-8b as the Causative Agent of an Outbreak of Inclusion Body Hepatitis in a Commercial Broiler Farm in Greece. Veterinary Sciences. 2022; 9(4):160. https://doi.org/10.3390/vetsci9040160

Quip Labs. (2019, July 22). Avian adenovirus. Quip Labs. Retrieved May 13, 2022, from https://quiplabs.com/avian-adenovirus/

Image from: http://www.virology.net/Big_Virology/EM/Adeno-FD.jpg