Fowl Adenovirus: Pathogenesis and Control

Fowl adenovirus (FAdV), belonging to the Aviadenovirus genus of Adenoviridae family, poses an increasing threat to poultry industry across the globe. In particular, the occurrence of hepatitis hydropericardium syndrome (HHS) in flocks in China has caused severe economic losses to stakeholders since 2015. Some serotypes of the FAdVs, especially FAdV-4, -2, -7 and -11, are highly pathogenic to 3to 6-week-old chickens and responsible for HHS and inclusion body hepatitis (IBH). On the contrary, lines of evidence indicate that adenovirus could serve as an optimal vector to deliver protective antigens of other pathogens in host. This review mainly focuses on the pathogenesis and control of HHS, and discusses over the possible role of FAdV as a vector in controlling other avian diseases.