Vol. 12, Issue 7 (2023)

Author(s):
K Anbu Kumar, P Devendran and PL Sujatha

Abstract:
Newcastle disease virus (NDV) causes a high disease burden to the global poultry production as well as infection in other avian species. Understanding the molecular epidemiology of NDVs in a region is essential in developing and deploying appropriate vaccine strains to control the disease burden. This study utilized 83 publicly available full length F gene sequences of NDVs from India, including all avian species. The recently updated unified phylogenetic classification system and revised nomenclature for Newcastle disease virus was used to delineate the Indian NDVs. The analysis of the dataset revealed the presence of genotypes I, II, III, IV, VI, VII, XIII and XXI in India. Among these, genotypes VI, VII and XXI are identified for the first time based on the updated unified phylogenetic classification system. The study reaffirmed the predominance of NDV genotypes XIII and II in chicken in India, with XIII being the highest circulating genotype (51.8%) among the analysed sequences followed by genotype II at 31.3%. All the currently used vaccine strains in India group under the genotype II, except the vaccine strain Avinew which aligned to the genotype I. The laboratory strain Mukteswar, originally isolated in the 1940s, grouped to the genotype III. The genotypes VI and XXI were exclusively from pigeons. The study highlights the high diversity of circulating NDV in India among chicken and other avian species.