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Texas’ Toxic Coastal CrittersTexas’ Toxic Coastal Critters
Meridith ByrdMeridith ByrdGulf of Mexico Coastal Ocean Observing SystemGulf of Mexico Coastal Ocean Observing System
Recreational Boaters WorkshopRecreational Boaters Workshop
May 28, 2009May 28, 2009
Red Tide Gambierdiscus toxicus Vibrio vulnificus
What is red tide?Alexandrium sp. bloom Penn Cove, Coupeville, WA www.serc.carleton.edu
Noctiluca sp. bloom, Southern California
Karenia brevis bloom, Charlotte Harbor, FL www.fiu.edu
• Dinoflagellate• single-celled algae• plant and animal traits• two flagella (locomotion)• 15 μm in length (2000 per inch)
Texas Red Tide: Karenia brevis
photo courtesy TDSHS
Tracy Villareal, UT Marine Science Institute
San Jose Island Oct 3, 2006
Texas Red Tides• 8 major red tides since 1986
• 60 million fish killed• 2006 most recent bloom
• Major blooms in late summer or fall• start in the Gulf, currents transport bloom to
shore
• Once inshore can last days to months• Ship channels• Estuarine areas• Manmade harbors• Subdivision canals• Jetties
Port Mansfield, 1999
North Padre Island 2006
2006 Red Tide Fish Kills
San Jose Island Matagorda Island Cedar Bayou Mustang Island Padre Island Aransas Bay Redfish Bay Mesquite Bay Corpus Christi Bay
22% gulf menhaden 21% Atlantic bumper 14% worm eel 11% gulf whiting 9% mullet 8% pinfish / pigfish 7% ladyfish 5% Atlantic croaker
3% hardheads, red drum, snook, sand trout, jacks, snapper, others
Where does it come from?
Low salinity (20 ppt)
Cold water (59o F)
What causes a bloom to end?
Resident population in Gulf of Mexico.
Padre Island Oct 5, 2005
How often do blooms occur and why? Florida: yearly
Texas: ~5 years
October 13, 2005Corpus Christi Bay
Water discoloration easily seen from the air.
• Neurotoxin: damages or destroys nerve tissue
• enters through fishes’ gills• attacks central nervous
system: paralysis• accumulates in fishes’
organs• seabirds, dolphins, turtles
• accumulates on seagrasses• green sea turtles, manatees
Brevetoxin
www.nepa.gov
commons.wikimedia.org
TPWD photo
Brevetoxin in shellfish
• concentrates in filter-feeding shellfish (oysters, mussels, clams, whelks)• toxin levels can remain elevated for
weeks to months • toxin heat-stable, NOT destroyed by
cooking
• Neurotoxic Shellfish Poisoning• lips, tongue go numb or tingle• GI symptoms• dizziness• reversal of hot and cold sensations
• Fish and crustaceans do not typically cause NSP
Texas Department of State Health Services
(TDSHS)• Responsible for seafood
safety.
• Criteria for bay closures:• Cell counts > 5000 cells per liter• Any detectable levels of toxin in
shellfish
• Reopening bays can take weeks to months after red tide has dissipated
Maryland DNR photo
TDSHS photo
Brevetoxin: Human Health Effects
• Aerosols cause: • skin irritation• coughing• sneezing• itchy, watery eyes• runny nose• wheezing, shortness
of breath
• Symptoms depend on:• Cell concentration• Wind direction• Wind velocity• Wave action
Calm day: lessened
symptoms
Rough surf: severe effects even with low cell numbers
www.tpwd.state.tx.us/hab/redtide
www.dshs.state.tx.us/seafood/default.shtm
“seafood”
Red Tide Brochure
To report a suspected
red tide:
281-842-8100512-389-4848
(TPWD 24 hr line)
Ciguatera Fish Poisoning: a New Concern in the
Northwestern Gulf of Mexico
big thanks to Tracy Villareal, UTMSI and Andy Reich, FL Dept of Health
Ciguatera Fish Poisoning
• seafood toxicity that produces gastrointestinal, neurological, and cardiovascular symptoms
• can be fatal
• most cases are less severe although recovery may take weeks to years
• has no laboratory test - it is a diagnosis of exclusion
• over 400 species of tropical fish reported to be ciguatoxic
Halstead, 1967
slide courtesy Tracy Villareal, UT Marine Science Institute
Typically associated with coral reefs on islands
Outbreaks are poorly understood
Multiple routes through food web to predators (Kelly et al. 1992)
Early European explorers reported sickness from eating fish
1511 Atlantic Ocean
1601 Indian Ocean
1606 Pacific Ocean
after Halstead 1967
slide courtesy Tracy Villareal, UT Marine Science Institute
Harmful Algal Bloom Food-borne Illnesses
Documented FATALITIESAmnesic Shellfish Poisoning (ASP)Paralytic Shellfish Poisoning (PSP)CiguateraVenerupin Shellfish poisoning (VSP)Clupeoid Fish Poisoning
REALLY UNPLEASANT (no known fatalities)Diarrhetic Shellfish Poisoning (DSP)Neurotoxic Shellfish Poisoning (NSP)
slide courtesy Tracy Villareal, UT Marine Science Institute
Have you had ciguatera? Fish eaten, followed by these symptoms within 72 hours
Some of these:
• abdominal pain• vomiting• diarrhea• nausea
1 of these:• slow heartbeat• numbness,
burning, or pricking around the mouth,
• sensation of temperature reversal
AND
http://www.cdc.gov/nceh/ciguatera/instructions.htm
slide courtesy Tracy Villareal, UT Marine Science Institute
ADDITIONAL SYMPTOMS• extremity numbness • tingling, pricking, burning, or creeping on
the skin• pain in the joints, muscle pain• malaise (not feeling right) • itching• headache• dizziness• metallic taste• visual disturbances• toothache, feeling of loose teeth
slide courtesy Tracy Villareal, UT Marine Science Institute
• 50,000 - 500,000 people affected annually around the globe (Fleming et al. 1998)
• significant under-reporting• difficulties confirming cases and no laboratory test• CDC estimates only 2%-10% cases reported in the US
• 32% of MDs in a ciguatera-endemic area (Dade County, FL) could not diagnose it
• only 17% knew the correct treatment (McKee et al. 2000)
• 95% of the medical costs associated with algal toxins in the U.S. are due to ciguatera
slide courtesy Tracy Villareal, UT Marine Science Institute
Ciguatera: Poorly Understood
Case study: 1999 Amberjack served in a Chicago restaurant led to a cluster outbreak of 21 cases
only 2 were diagnosed with ciguatera
Diagnoses included allergies multiple sclerosis rheumatologic diseases dental abnormality
Specialists in urology, infectious disease, rheumatology and odontology had been consulted.
slide courtesy Tracy Villareal, UT Marine Science Institute
Ciguatera in the Gulf of Mexico• Few documented cases, no public perception of a threat
• Fish migration behavior a factor• toxin possibly acquired elsewhere, transported seasonally
• Significant human activity in the Gulf is altering habitat,
particularly in the northern Gulf • no oil production platforms before 1942• now there are about 4000• possibly the largest artificial reef complex in the world.
• Historically tied to island complexes, not continental shelves
• Gambierdiscus toxicus has been found on platforms along the continental shelf
slide courtesy Tracy Villareal, UT Marine Science Institute
Rigs, Coral Reefs, Artificial Reefs
Villareal et a. 2007
fish migrations
G. toxicus -Present on
platforms and Sargassum
slide courtesy Tracy Villareal, UT Marine Science Institute
Coral reef Artificial Reef Oil rig
www.aslo.org
• A highly publicized case in Galveston, TX created a local media frenzy
• Other cases started to surface: TX-AL• Increased awareness
2007: change in type of ciguatoxic fish and number of cases
slide courtesy Tracy Villareal, UT Marine Science Institute
FDA Advisory: Feb 5, 2008Within 50 miles of Flower Gardens
Within 10 nautical miles of Flower Gardens
amberjack barracuda
yellow jack horse-eye jack
king mackerel
hogfishdog snapperblackfin snapper
yellowfin grouperscampgag grouper
marbled grouper
Ciguatera Fish Advisory
Ciguatera Brochure
slide courtesy Andy Reich, Florida Department of Health
The genus
Vibrio
• Naturally-occurring bacteria• ~ 3 dozen species
Not all cause illness in humans• Oceans, brackish water
worldwide• Warm temperatures
V. cholerae
V. vulnificus
V. parahaemolyticus
slide courtesy Kirk Wiles, Texas Department of State Health Services
Vibrio vulnificus• Occur naturally in warm coastal waters
• Levels highest April-October
• Accumulates in tissues of filter-feeding shellfish
• oysters, clams• does not affect appearance, taste, odor• food poisoning if raw or undercooked
• Can infect wounds • Serious consequences in
at-risk people
slide courtesy Kirk Wiles, Texas Department of State Health Services
Gastroenteritis (food poisoning)• Occurs after consumption of contaminated food,
particularly raw oysters
• Vomiting, diarrhea, cramps
Wound infection• Occurs after a wound comes in contact with seawater
containing V. vulnificus
• Swelling, redness, pain
• Often requires surgical debridement, amputation
Primary septicemia• Occurs following either of above syndromes
• Fever, chills, skin lesions, drop in blood pressure, shock
• 50% of cases are fatal
slide courtesy Kirk Wiles, Texas Department of State Health Services
At-risk population includes those with:
• Liver disorders (hepatitis, alcoholism, cirrhosis)• risk of death is 200 times greater than those without
• Diabetes • Immunocompromising conditions
• HIV/AIDS• Cancer• Autoimmune disorder (lupus)
• Hemochromatosis (metabolic iron disorder)• Gastric surgery or take antacids for ulcers
slide courtesy Kirk Wiles, Texas Department of State Health Services
People without any risk factors• May develop short duration gastroenteritis
1 – 3 days after eating affected shellfish
• May develop skin infection 1 – 3 days after having wound contact with saltwater
• Do not develop septicemia
• Have no long-term consequences
• Infections can be treated successfully with antibiotics, if detected early enough
slide courtesy Kirk Wiles, Texas Department of State Health Services
Persons who are at risk:• Should never eat untreated raw oysters• Could eat post-harvest treated oysters
• “Processed to reduce V. vulnificus to non-detectable levels”
• high pressure• high temperatures• freezing temperatures
• Should not go in salt water with an open wound• Are 80 times more likely to develop bloodstream
infections than healthy people (U.S. Centers for Disease Control)
The infectious dose for V. vulnificus is not known
slide courtesy Kirk Wiles, Texas Department of State Health Services
WARNING: The next slide shows graphic pictures of wounds infected
with Vibrio vulnificus
slide courtesy Kirk Wiles, Texas Department of State Health Services
Examples of wound infections caused by Vibrio vulnificus.
slide courtesy Kirk Wiles, Texas Department of State Health Services
To Avoid Infection:
• Do not contact seawater with open wound.
• If you do, wash wound thoroughly with soap and water.
• If wound becomes red or inflamed seek medical treatment.
• Do not delay seeking treatment.
slide courtesy Kirk Wiles, Texas Department of State Health Services
1999 thru 2003 - Average Concentrations of Vibrio vulnificus in Galveston Bay Oysters
1.00
10.00
100.00
1,000.00
10,000.00
100,000.00
1,000,000.00
Dates
MPN/
g
0
10
20
30
40
50
60
70
80
90
100
Water
Temp
. (F)
1999 2000 2001 2002 2003
Meridithhi
Vibrio infections in Texas
V. vulnificus Infections in Texas• Average about 12 cases per year
• Summer consumption of Gulf coast raw oysters • Some wound infection, septicemia cases• 8:1 male/female ratio for V. vulnificus infections
• more males eating raw oysters, fishing?
• Average a few deaths per year• Almost all from V. vulnificus
• Virtually all have one or more risk factors for V. vulnificus infection
slide courtesy Kirk Wiles, Texas Department of State Health Services
V. vulnificus Infections in Texas
• Many cases likely not reported• food poisoning, minor infections
• Case counting by TDSHS depends on:• Ill person seeking medical attention• Health care provider must:
• obtain specimen for culturing• suspect Vibrio • request specific test
• Laboratory detecting agent in specimen if present• Laboratory or health care provider reporting to local
or state health department
• Numbers of reported cases rise with public awareness
slide courtesy Kirk Wiles, Texas Department of State Health Services
FOR MORE INFORMATION:
www.safeoysters.org
Sea Grant
Texas Department of State Health Services (TDSHS)
Kirk Wiles
512-834-6757
