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

TPWD HAB website: www.tpwd.state.tx.us/hab

Meridith Byrd 361-575-6306

meridith.byrd@tpwd.state.tx.us