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Texas’ Toxic Coastal Critters Meridith Byrd Gulf of Mexico Coastal Ocean Observing System Recreational Boaters Workshop May 28, 2009 Red TideGambierdiscus toxicusVibrio vulnificus
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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
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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
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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
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North Padre Island 2006
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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
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Where does it come from? Low salinity (20 ppt) Cold water (59 o 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
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October 13, 2005 Corpus Christi Bay Water discoloration easily seen from the air.
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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
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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
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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
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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
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Calm day: lessened symptoms Rough surf: severe effects even with low cell numbers
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www.tpwd.state.tx.us/hab/redtide
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www.dshs.state.tx.us/seafood/default.shtm “seafood”
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Red Tide Brochure To report a suspected red tide: 281-842-8100 512-389-4848 (TPWD 24 hr line)
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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
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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
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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
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Harmful Algal Bloom Food-borne Illnesses Documented FATALITIES Amnesic Shellfish Poisoning (ASP) Paralytic Shellfish Poisoning (PSP) Ciguatera Venerupin 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
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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
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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
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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
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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
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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
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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
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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
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FDA Advisory: Feb 5, 2008 Within 50 miles of Flower Gardens Within 10 nautical miles of Flower Gardens amberjackbarracuda yellow jackhorse-eye jack king mackerel hogfishdog snapperblackfin snapper yellowfin grouperscampgag grouper marbled grouper
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Ciguatera Fish Advisory
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Ciguatera Brochure slide courtesy Andy Reich, Florida Department of Health
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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
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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
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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
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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
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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
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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
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WARNING: The next slide shows graphic pictures of wounds infected with Vibrio vulnificus slide courtesy Kirk Wiles, Texas Department of State Health Services
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Examples of wound infections caused by Vibrio vulnificus. slide courtesy Kirk Wiles, Texas Department of State Health Services
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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
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Meridith hi
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Vibrio infections in Texas
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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
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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
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FOR MORE INFORMATION: www.safeoysters.org Sea Grant Texas Department of State Health Services (TDSHS) Kirk Wiles 512-834-6757
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TPWD HAB website: www.tpwd.state.tx.us/hab Meridith Byrd 361-575-6306 meridith.byrd@tpwd.state.tx.us
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