Cause of Early Mortality Syndrome (EMS) Found

On May 1, 2013, the Global Aquaculture Alliance (GAA) announced that Dr. Donald Lighter, a pathologist at the University of Arizona, has discovered the cause of Early Mortality Syndrome (EMS), a disease that costs the global shrimp farming industry billions of dollars each year.

The cause of EMS Syndrome has been found - Photo: Phan Thanh Cuong

Lighter's team also showed that EMS is caused by a single strain of a fairly common bacterium, Vibrio parahaemolyticus, that has been infected by a virus known as a bacteriophage that releases a powerful toxin. The bacterium is transmitted orally, lives in the shrimp's digestive tract, and then produces a toxin that destroys tissue and causes dysfunction of the hepatopancreas, the shrimp's digestive organ.

Research also continues to develop diagnostic tests for rapid detection of EMS, allowing for improved management in hatcheries and ponds. Research also allows for better assessment of the risks involved in importing frozen shrimp or other products from countries affected by EMS.

Several countries have also implemented policies to prevent the importation of frozen shrimp and other products from countries affected by EMS. Dr. Lighter also said that frozen shrimp could be considered a low-risk source of infection for wild shrimp and the environment because EMS-infected shrimp are typically very small and are not traded internationally. There have also been unsuccessful attempts to propagate the disease using frozen tissue, Dr. Lighter added.

According to (Vietnam Fisheries) - LC