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Taura Syndrome Virus, Venezuela
March 14, 2005
Impact Worksheet |
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Summary: On March 8, 2005, Taura syndrome (TS)
in shrimp was reported to the OIE by Venezuela.
This is the first reported occurrence of TS in shrimp in Venezuela.
TS is caused by the Taura syndrome virus and has caused outbreaks in farmed
shrimp in the Americas, Indonesia
and China since first being described
in Ecuador in 1992. The last reported
case of TS in the US was in June
of 2004 in Texas.
Shrimp production in Venezuela
accounted for less than 1% of world production in 2002. In 2004, the US
imported 16.3 thousand metric tons of cooked and frozen shrimp and shrimp
products from Venezuela, which was
a 63% increase from 2003.
How extensive is Taura syndrome in Venezuela,
and what was Venezuela’s
disease status prior to the outbreak?
Venezuela reported
an outbreak of TS in shrimp to the OIE on March 8, 2005. The affected species
of shrimp was not identified in the report. This is the first reported outbreak
of TS in Venezuela. At the time
of the report, 26 outbreaks had been identified in 3 different states. The
states affected by the outbreaks are Zulia State (14), Falcon State (8), and
Nueva State (4). Deaths reported were 700 million, with 2 billion shrimps
considered susceptible. The shrimp were positively diagnosed with TS using
RT-PCR at the Aquaculture Pathology Laboratory at the University of Arizona
in Tucson, Arizona, which is an OIE Reference Laboratory for TS. Mortality
was seen in shrimp after clinical signs of TS were observed. The clinical
signs seen were red points in the telson, vacillating swimming and soft carapace
in shrimp weighing less than 5 grams. The origin of the infection is unknown
at this time; spread has been through avian feces, cannibalism and transport
of sick animals. Control measures being implemented are zoning and movement
control within the country.
Source: OIE Disease Information Report
What is Taura syndrome?
TS is caused by the Taura
syndrome virus, a single-stranded RNA virus in the family Picornaviridae.
TS generally occurs over the course of a single molt in juvenile shrimp and
may have a sudden onset within 5-20 days or a more chronic course of several
months. Signs of infection include weakness, a soft shell, an empty digestive
tract, and diffuse expansion of red chromatophores in the appendages. Mortality
can vary from 5-95 percent. Farmed shrimp species vary in their
susceptibility to TS.
Potential routes for introduction
of shrimp viral diseases to aquaculture facilities include infected broodstock,
contaminated vehicles, containers, and other fomites, and transfer by birds
and bird feces. For additional information about potential routes of shrimp
viral disease transmission, please see the April 23, 2004
impact worksheet about white spot disease of shrimp in the US. This worksheet can be found at http://www.aphis.usda.gov/vs/ceah/cei/taf/iw_2004_files/wsd_0404_files/wsd_us_0404.htm.
TS was last seen in the US in June of 2004 in an outbreak
that occurred in Pacific white shrimp in farmed shrimp in Texas.
Sources: Brock JA. Special topic review: Taura
syndrome, a disease important to shrimp farms in the Americas.
World J Micro Biotech 1997;13:415-418. Fact Sheet for Taura syndrome virus.
Gulf States Marine Fisheries Comission, http://nis.gsmfc.org/nis_factsheet.php?toc_id=6,
accessed June 14, 2004. An Initial Survey of Aquatic Invasive Species Issues
in the Gulf of Mexico Region, Gulf of Mexico Program, US Environmental Protection
Agency, August 2001, http://nis.gsmfc.org/pubs/Initial%20Survey%20of%20Invasive%20Species.pdf,
accessed June 15, 2004, CEI Impact Worksheets.
What is Venezuela’s
place in the international market for shrimp and shrimp products?
During 2001 and 2002, Venezuela’s
shrimp and prawn production leveled off at about 22,000 metric tons after
more than doubling between 1999 and 2001. Shrimp and prawn production in
Venezuela amounted to less than 1%
of world production in 2002. Shrimp production data shown in Table 1 represent
both wild caught and farmed shrimp. The most recent FAO figures for shrimp
production in Venezuela are for 2002.
Table 1: Shrimp Production, Venezuela,
2001 and 2002
| |
2001 |
2002 |
Production
(metric
tons) |
Production
(metric
tons) |
%
of World Production |
Shrimp, prawns |
22,640 |
21,981 |
<
1% |
Source: United Nations FAO
What are the US
imports of shrimp or shrimp products from the Venezuela?
Between 2003 and 2004, US imports of Venezuelan shrimp
products rose from 10 thousand to 16.3 thousand metric tons, an increase of
63%. Over the same two year period, the value of Venezuelan shrimp exports
to the US rose by 40%, from $61 to
almost $86 million. Shrimp products imported from Venezuela
by the US are cooked and frozen.
Ninety-five percent of the shrimp imports from Venezuela
are cooked. Cooking shrimp is considered an appropriate method to mitigate
risk of virus transmission with respect to shrimp.
Table 2: US imports of shrimp products from Venezuela,
2003 and 2004
Product |
2003 |
20041 |
| |
$value
(1,000’s) |
Quantity
(metric
tons) |
$value
(1,000’s) |
Quantity
(metric
tons) |
Shrimps, prawns,
cooked, frozen (030613) |
61,070 |
10,003 |
85,711 |
16,268 |
Source: World Trade Atlas
1 2004 preliminary data
What are Canada
and Mexico’s imports
of shrimp or shrimp products from Venezuela?
Preliminary data indicate that during 2004 Canada
and Mexico respectively imported
104 and 2,214 metric tons of shrimp products from Venezuela.
Canada’s 2004 shrimp imports have
an estimated value of about $700,000 (Canadian dollars), while Mexico’s
imports of Venezuelan shrimp during 2004 are valued at $10,626,449 (US dollars).
Source: World Trade Atlas
What is the level of passenger traffic arriving in the
United States from
Venezuela?
During 2004, an estimated 620,796 air passengers arrived
in the US from flights originating
in Venezuela. As part of USDA, APHIS-PPQ’s
Agricultural Quarantine Inspection Monitoring system, 1,432 air passengers
arriving in the US from Venezuela
in fiscal year 2004 were sampled for items of agriculture interest. Of the
sampled passengers, one passenger was found to be carrying fish or seafood
which could be considered a potential risk.
Source: Office of Travel
& Tourism Industries, US Department of Commerce, USDA APHIS-PPQ Agricultural
Quarantine Inspection databases, Bureau of Transportation Statistics.
CEI’s plans for follow up:
No follow-up is currently planned regarding the outbreak
of TS in Venezuela. If you need
more information or if you want to comment on this worksheet, you may reply
to this message, or contact Cynthia Johnson at 970-494-7332 or Wolf Weber
at 970-494-7222.