First molecular detection of avian polyomavirus from captive psittacine birds in Bangladesh, together with confirmation of beak and feather disease virus co-infection

Virusdisease. 2023 Sep;34(3):440-445. doi: 10.1007/s13337-023-00829-8. Epub 2023 Jul 11.

Abstract

Avian polyomavirus (APV) is an emerging pathogen in many parts of the world responsible for causing significant mortality in captive psittacine birds. The virus spreads slowly, and transboundary movement of birds is one of the potential risk factors for the virus introduction in the naïve population. Bangladesh allows the import of birds, however there is currently no surveillance to screen for APV. Since we confirmed beak and feather disease virus (BFDV) infection in the captive population in our earlier investigation, we hypothesized that APV may also be circulating in Bangladesh. Feather samples were collected from 100 birds (90 psittacine and 10 non-psittacine). The polymerase chain reaction (PCR) was used to detect viral DNA together with sequencing and phylogenetic analysis. This first pilot study confirmed the presence (7%, 7/100) of APV in captive psittacine birds of Bangladesh and almost half (4%, 4/100) of the APV positive birds had the BFDV co-infection. All the PCR-positive birds were asymptomatic and found in live bird markets (LBMs). No significant variation was observed in the detection rate considering species (P = 0.94), age (P = 0.39) or sex (P = 0.55) of birds. According to the results of the phylogenetic study, the APV isolates found in Bangladesh appear to be unrelated to isolates from other geographical areas. These findings provide an evidence of APV circulating in Bangladesh, with or without the co-infection of BFDV. Additional studies are needed to investigate the occurrence of APV/BFDV co-infection in the larger population of Bangladesh and in countries where transboundary bird interaction with Bangladesh may be possible.

Keywords: Avian polyomavirus; BFDV; Fledging disease; Phylogenetic analysis; Prevalence.