Disease costs Asian shrimp sector $20 billion
“Shrimp disease has resulted in huge national income losses – despite compensatory price rises in response to supply shortage – amounting to billions of dollars annually and at least $20bn globally over the last decade,” said Shinn.
White spot syndrome virus is one of the most widespread pathogens, typically resulting in an 80-100 percent loss of stock. According to Shinn, infections in 3,907ha of shrimp ponds in the Mekong Delta, Vietnam in 2015 resulted in losses estimated at $8.02mn.
Acute hepatopancreatic necrosis disease (AHPND) or the early mortality syndrome (EMS) is another disease that had had devastating economic impacts for Asian shrimp, particularly in Thailand.
Following the AHPND/EMS outbreak, shrimp productivity in the Southeast Asian nation fell from a peak of 10.6 tonnes/ha in 2010 to 4.13 tonnes/ha in 2013.
In 2015, in the Mekong Delta, AHPND contributed to a loss of $1.84mn for monodon, and $8.92mn for vannamei; that is roughly a shortfall of $796 and $3,867 per hectare, respectively.
Shinn pointed out that national losses to date are estimated to be more than $5.01bn, with value added costing around $1.7bn-$2bn annually. An estimated 100,000 jobs have been lost as a result of infections.
The emergence of the fungal microsporidian Enterocytozoon hepatopenaei (EHP), which is the causative agent of hepatopancreatic microsporidiosis has had an impact on shrimp growth.
EHP spores are persistent and can be transmitted horizontally between shrimp, particularly in earthen rearing ponds. A Thai survey of 150 pre-stocked ponds found prevalence at 49 percent.
Shinn added that with the consequential slowed growth and early harvest, production costs are not covered and losses are around $32,000/ha per culture cycle. ■