Shrimp ailment to hit global supply

Early mortality syndrome (EMS), the disease which caused serious damage to the shrimp industry in countries such as Vietnam and Thailand, is now spreading widely. Outbreak of the disease in China and Indonesia is now reported, causing a sharp fall in the supply of the commodity which triggered international price rise.

Chinese production was very badly hit due to the disease in 2009. Some countries had even banned import of shrimp from southeast Asian countries. According to reports, it would take at least eight to 10 months to recoup the production loss. Production in Malaysia, too, has been affected due to EMS.

Shrimp prices have reached record in Japan and traders now see no hope of price relief going into the year-end holiday season. According to reports, global shrimp production will be down 10 per cent this year. Global prices have risen $1-2 per kg, on an average, this month.

According to market analysts, the present market condition might be a boon to exports from India and Ecuador, where disease has not spread so far. The average global price has increased to $9-9.5 a kg (for 20-30 count) from $7-7.5 a few weeks ago.

Processing plants in east Asian countries have to depend on import from India in order to meet their commitments with European and US importers. Countries such as Vietnam and Taiwan are importing more shipments from India for export purpose. Rise in local demand in Korea also caused warming up in global prices. Chinese import has also increased around 28 per cent during the past six months. Supply from Thailand, the world's second largest shrimp producer, may fall about 50 per cent this year from a normal production size of 500,000 tonnes a year.

To protect Mexican shrimp aquaculture from disease, the Secretariat of Agriculture, Livestock, Rural Development, Fisheries and Food ordered temporary suspension of shrimp from China, Vietnam, Malaysia and Thailand.

The Philippines had stopped import of live shrimps from May onwards. The Bureau of Fisheries and Aquatic Resources (BFAR) of the Philippines has also banned the entry of crabs and lobsters, which can carry and transmit the disease. BFAR said it is also monitoring the spread of EMS in Singapore, Myanmar, Brunei and Cambodia.

Meanwhile, a research team led by Donald Lightner at the University of Arizona found that EMS is caused by a bacterial agent, which is transmitted orally, colonises the shrimp gastrointestinal tract and produces a toxin that causes tissue destruction and dysfunction of digestive organ known as the hepatopancreas. It does not affect human beings.

Lightner's team identified the EMS pathogen as a unique strain of a relatively common bacterium, Vibrio parahaemolyticus, that is infected by a virus known as a phage, which causes it to release a potent toxin.