Science et technologie vétérinaires

Newcastle disease is an acute viral disease that affects both domestic and wild bird species around the world. It is a costly and widespread disease in most poultry-producing countries, including Ethiopia. Newcastle disease virus is a member of the genus orthoavulavirus, species avian orthoavulavirus (AOAV-1), and a new subfamily Avulavirinae of the family Paramyxoviridae that causes Newcastle disease. The virus is a non-segmented, single-stranded, enveloped, negative-sense RNA virus. The virus's genome contains six open reading frames that encode six structural proteins and two non-structural proteins. The virus's two major surface glycoproteins are hemagglutinin-neuraminidase and fusion protein. The hemagglutinin-neuraminidase protein mediates virus binding to host target cells, whereas the fusion protein facilitates viral envelope fusion with the cellular membrane of the target cells. Based on serological and phylogenic examination of the virus, fifteen distinct avian orthoavula virus serotypes are present. Strains are further grouped into three main pathotypes depending on their virulence and clinical signs: velogenic, mesogenic, and lentogenic. Newcastle disease is the most challenging avian disease in Ethiopia, resulting in significant economic losses for the poultry sector. The disease causes abrupt death with a 100% fatality rate to subclinical infection in chickens. The economic losses are associated with high mortality, morbidity, disease containment measures, outbreak eradication, and decreased egg production from breeder flocks. Regular outbreaks of the disease have posed a severe threat and confronted Ethiopia's burgeoning chicken sector. In endemic nations, there is a need to strengthen prevention and control strategies for Newcastle disease. As a result, this review article provides current scientific information on the Newcastle disease virus, including pathogenesis, antigenic variants, genetic diversity, current taxonomic classification, epidemiology, and various diagnostic techniques, in order to highlight the disease's control and prevention directions. Its goal is to combine numerous study findings from various sites and assess the disease's state in Ethiopia. Finally, to emphasize the poultry industry's economic importance in the country and to make recommendations for efficient management and prevention measures.