ABSTRACT
Arthropoda comprise the largest proportion of the world’s animals; this phylum, as would be expected, has significant impact on all ecosystems. The effects on man alone, directly, and indirectly range from major threats to such mainstays as agriculture, forestry, and human health to its benefits as aids to mineralization of organic products, pollination, and the direct production of food. Occurrence of viruses in marine crustaceans does not mean that a disease will necessarily result; many are latent for large parts of the crustacean life cycle and some have never been associated with any pathological condition. Infections occurring frequently in the larval stages are enhanced by stress induced by overcrowding, abnormal temperatures, and pollutants, among others. Gram-negative bacterial septicemic disease or vibriosis has been observed in captured marine crustaceans or cultured populations exposed to stress where it can result in severe mortalities. The bacterium does not possess invasive properties.
