Characterization and phylodynamic analysis of new infectious bursal disease virus variants circulating in Argentina

JUAN JATON; LAURA CAMILA LOZANO; PABLO GAMBINI; MARINA PONTI; EVANGELINA GÓMEZ;; GUIDO ALBERTO KÖNIG; SILVINA CHIMENO ZOTH

POULTRY SCIENCE

POULTRY SCIENCE ASSOC INC

Año: 2024

0032-5791

Infectious Bursal Disease is a highly contagious disease that affects young chickensand leads to significant economic losses. Its causal agent is a double-stranded RNAvirus that, due to its high error rate during the replication process, gives rise to aconstant generation of new virus variants. Until 2014, strains of Infectious BursalDiseases Virus (IBDV) belonging to genogroup 4 predominated in Argentina, but therehave been no reports since then regarding the circulating genogroups in poultry. In thisstudy, 11 recent sequences of Argentine from the hypervariable region of VP2 protein(hvVP2) were analyzed to determine their genogroup, origin, evolution, and amino acidsequence. Samples from chickens showing signs of IBDV infection were collected, andthe hvVP2 region was amplified using RT-PCR, followed by sequencing. The resultsindicated that the analyzed strains belong to genogroup 2, with an estimatedevolutionary rate of 1.74x10-3 substitutions/site/year. It is believed that thepredominant group of sequences began to spread in Argentina around 2014 and hadits origins in China. Another sample is related to strains from South Korea and is notclosely linked to the main group. Furthermore, the predicted amino acid sequencesshow similarity to strains that can evade vaccine-induced immunity. These findingsunderscore the importance of active surveillance in poultry to mitigate losses caused by IBDV