Here we report the biological and molecular characterization of a virulent genotype VII Newcastle disease virus (NDV) circulating in Venezuela and the assessment of the vaccination efficacy under field conditions compared to controlled rearing conditions. Biological pathotyping showed a mean embryo dead time of 50 h and an intracerebral pathogenicity index of 1.86. Sequence-based phylogenetic a...

Five weeks old guinea fowls were inoculated intraocularly with a 20% bursal suspension containing a local Nigerian isolate of infectious burfa! disease virus (IBDV) which had a bursal lesion titre of 10· per 0.5 mI. No clinical signs were observed. Gross lesions were absent and microscopic lesions were not found in the bursa, spleen and kidney on days 3 and 5 post infection (PI). IBDV antigen w...

The Infectious Bursal Disease (IBD) is a contagious viral disease that affects young chickens and may cause high morbidity and mortality. As the virus is very resistant to the environment, vaccination is required in case of high infection pressure. Due to variations in the virulence degree of the vaccines available to control IBD, this study aimed at evaluating the pathogenicity and immunogenic...

This introduction provides a telegraphic overview of the processes of zoonotic viral emergence, the intricacies of host–virus interactions, and the distinct role of biological transitions and modifying factors. The process of emergence is conceptualized as two transition stages which are common and required for all disease emergence, (1) human contact with the infectious agent and (2) cross-spe...

It is widely recognized that fragile states are key symptoms of under-development in many parts of the world. Such states are incapable of delivering basic services to their citizens and political violence is commonplace. As of yet, mainstream development economics has not dealt in any systematic way with such concerns and the implications for development assistance. This paper puts forward a f...

Sequencing and phylogenetic analysis based on the nucleotide sequence of the gene encoding VP2 protein was carried out in order to characterize the agent of two outbreaks of infectious bursal disease in layer flocks in the state of Minas Gerais in 2004. The results indicate the outbreaks could be related to the vaccinal virus.