Prevalence of Fowl Adenovirus Serotype 4 and Co-Infection by Immunosuppressive Viruses in Fowl with Hydropericardium Hepatitis Syndrome in Shandong Province, China

Abstract

Fowl adenovirus serotype 4 (FAdV-4) is the pathogenic agent of hydropericardium hepatitis syndrome (HHS) in chickens and ducks, which has caused huge economic losses for the Chinese poultry industry since 2015. In order to objectively determine the prevalence and co-infection status of the virus in Shandong province in China, we analyzed a total of 679 clinical cases of chickens and ducks from 36 farms in the province. The results showed that the FAdV-4 infection rate was 65.2% (443/679), and the rate in breeder ducks was almost two-fold higher than that in breeder chickens (68.57% vs. 34.30%). Notably, co-infection by H9N2 avian influenza virus, infectious bursal disease virus, and/or chicken infectious anemia virus was very common in the 443 FAdV-4-positive cases. Furthermore, phylogenetic analysis of the hexon genes of four Shandong FAdV-4 isolates revealed that these strains clustered into Indian reference strains, indicating that the Shandong FAdV-4 strains might have originated in India. These findings provide the first data on the prevalence and co-infection status of FAdV-4 in Shandong province, which may serve as a foundation for the prevention of FAdV-4 in the field.

Experimental co-infection of variant infectious bursal disease virus and fowl adenovirus serotype 4 increases mortality and reduces immune response in chickens

“…Novel antigenic variant IBDV and FAdV-4 have both occurred frequently in China, recently causing huge economic losses [ 6 , 11 ], and FAdV co-infection with IBDV in chickens has been reported [ 16 , 18 ]. In this study, we developed a co-infection model in SPF chickens using the novel variant IBDV strain ZD-2018-1 and the FAdV-4 isolate HB1501 to explore the interaction between these infections.…”

“…Since 2015, FAdV-4 has occurred in several provinces in China [ 11 , 13 – 15 ] and attracted much attention in the poultry industry. Furthermore, some studies have reported that poultry can become coinfected with FAdV and other avian diseases, such as avian influenza virus (AIV), IBDV, and chicken infectious anemia virus (CIAV) [ 16 – 19 ]. FAdV co-infection with other infectious agents has become a non-negligible issue.…”

Special Issue “Emerging Viruses: Surveillance, Prevention, Evolution, and Control”

“…We received several papers on veterinary viruses. Yu et al [19] present data on the prevalence and co-infection of fowl adenovirus. Meng et al [20] identify and characterize a novel fowl adenovirus and perform an immunoprotective evaluation of an inactivated FAdV-4 vaccine.…”

The Diagnosis and Molecular Epidemiology Investigation of Avian Hepatitis E in Shandong Province, China

“…It has been reported that severe HEV infections have occurred in several provinces in China since 2016 [10,3,11]. In recent years, outbreaks of BLS and HS syndrome in chicken ocks have gradually increased in Shandong province [10,12]. In order to investigate the causes of BLS and HS syndrome, and the epidemic characteristics of avian HEV in Shandong province, 18 cases of hepatomegaly and splenomegaly were collected for histopathology examination and pathogen detection, including HEV, MDV, FAdV, ALV, CIAV, and REV.…”