Taura syndrome is one of the most devastating diseases affecting the shrimp industry worldwide. Since its first description in Ecuador, it has spread to all shrimp producing countries in the Americas and outbreaks have been reported in many regions of Southeast Asia. Initially it was believed that the disease had a toxic etiology and was caused by pesticides used in banana plantations near shrimp farms. However, the infectious origin of the disease is now widely accepted. The Taura syndrome is on the list of notifiable diseases of the World Organization for Animal Health.
The disease has three phases that overlap: acute, transition and chronic. The cycle of the disease has been characterized in detail for the Litopenaeus vannamei. L. vannamei is particularly susceptible to this disease. After the infection either by cannibalism or exposure to water, the acute phase develops. In some individuals, clinical signs may appear as early as seven hours after they have been infected. The infected shrimp shows anorexia, lethargy, erratic swimming, opacity of the caudal musculature, soft cuticles and chromatophore expansion (red tail). The acute phase can last up to seven days and mortality rates of up to 95% have been observed.
The shrimp that manages to survive this first phase goes through a transitional stage (between 5 and 8 days after exposure). The characteristics of this phase are lesions in melanin of variable shape and size that can be seen in the head and tail of the shrimp.
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