Ciguatera Fish Poisoning Outbreaks Signal Need for Improvements in Prevention - New York, 2010-2011 John Hustedt, MPH Nathan Graber, MD, MPH Faina Stavinsky,

Ciguatera Fish Poisoning Outbreaks Signal Need for Improvements in

Prevention - New York, 2010-2011

John Hustedt, MPHNathan Graber, MD, MPH

Faina Stavinsky, MSNancy Clark, MA

Jessica Button, MSScott Martin, MD

OutlineOutline

• Background

• NYC Outbreaks

• Outbreak Response

• Challenges in Diagnosis

• Challenges in Testing for Ciguatoxin

• Challenges in Treatment

• Prevention

• Conclusions

Ciguatera Fish PoisoningCiguatera Fish Poisoning

• Ciguatera is a naturally occurring fish toxin that affects a wide variety of popularly consumed reef fish.

• Ciguatera and related toxins are derived from dinoflagellates, which herbivorous fish consume while foraging through macro-algae

• Ciguatera becomes more bioconcentrated as it moves up the food chain

Ciguatera Fish PoisoningCiguatera Fish Poisoning

• Humans ingest the toxin by consuming large predator reef fish such as barracuda, grouper, and amberjack

Ciguatera Fish PoisoningCiguatera Fish Poisoning

• Over 50,000 cases/year worldwide

• The toxin is tasteless and heat-stable

• Symptoms include diarrhea, abdominal cramps, nausea, headache, vomiting, numbness, and paradoxical dysesthesias

• Asymptomatic and symptomatic periods are variable; duration of illness can persist from several months to years

NYC CFP OutbreaksNYC CFP Outbreaks

NYC experienced an unusual increase in CFP cases in 2010-2011.

•29 Cases from 6 outbreaks (2010-2011)

•24 Cases from 4 outbreaks (2000-2009)

More cases in one year (Aug 2010-July 2011) than previous 10 years

Initial OutbreaksInitial Outbreaks

• August – September 2010 Three outbreaks and one individual case

involving thirteen cases All developed CFP like symptoms after

consuming barracuda Barracuda purchased at fish markets in three

boroughs and one restaurant.

Health AlertHealth Alert

Distributed health alert to physicians in November 2010.

Receiving physician reporting an

additional outbreak with eleven cases

All developed CFP like symptoms

after consuming grouper purchased

from a supermarket in queens

Additional OutbreaksAdditional Outbreaks

• July 2011 Two outbreaks involving five cases All developed CFP like symptoms after

consuming grouper Grouper consumed at two restaurants in

Manhattan

Case InterviewsCase Interviews• 24 cases were interviewed• Five cases were not aware what type of fish they consumed

 Table 1: CFP Cases Reporting Various Symptoms in NYC, 2010-11

Symptom # (%)

Diarrhea 20 69%

Difficulty walking 19 66%

Abdominal cramps 21 72%

Itching 16 55%

Nausea 15 52%

Headache 13 45%

Muscle ache 13 45%

Vomiting 13 45%

Numbness/tingling 11 38%

Dizziness 9 31%

Paradoxical dysesthesias 6 21%

NYC Outbreak ResponseNYC Outbreak Response

Four samples of fish consumed by cases were collected and tested positive for ciguatoxins

New York State Department of Agriculture and Markets (NYS DAM) and FDA traced all fish back to two distributors in Florida

NYC Outbreak ResponseNYC Outbreak Response

Analysis of CFP calls to American Association of Poison Control Centers from 2000-2010 showed:

Increase of 55% in NYC Decrease in 44% in Florida No change nationwide

Challenges in DiagnosisChallenges in Diagnosis• In South Florida, where CFP is considered endemic,

one study found that only 68% of physicians presented with a typical case of CFP diagnosed it correctly*

• In addition, it is estimated that only 2-10% of CFP cases are reported to health authorities**

• Raising awareness and increasing familiarity among health care providers is critical to increase reporting and investigation

• Releasing a health alert in NYC helped find an additional outbreak

Challenges in Testing for Challenges in Testing for CiguatoxinCiguatoxin

• No standardized, quick-turnaround test to identify CT in fish membrane immunobead assay using a color

change indicator– Studies show significant variation in sensitivity and

specificity

In vitro assay and liquid chromatography-mass spectrometry (LC-MS)

Challenges in TreatmentChallenges in Treatment

• Treatment options for CFP are limited and as of yet still unproven IV mannitol

– Numerous case reports– Recent double-blind, randomized control trial

Amitriptyline Fluoxetine GABApentin

PreventionPrevention

• Increase surveillance in areas where reef fish are consumed

• Increase provider awareness of CFP symptoms

• Trace back investigations to identify high-risk fishing areas

• Update HACCPs and consider banning fishing for certain species in high-risk areas to reduce exposure

• Develop a rapid test for CT to identify high-risk fish and reefs.

ConclusionsConclusions

• Identified unusual increase in CFP cases

• Used traditional public health investigation to track back source

• Importance of provider awareness and reporting

• Need to overcome challenges in identifying CT in fish and preventing toxic fish coming to market

ReferencesReferences

* McKee D, Fleming LE, Tamer R, Weisman R, Blythe DG. Physician diagnosis and reporting of ciguatera fish poisoning in an endemic area. Harmful Algal Blooms 2001; 451-53. 

** Friedman MA, Fleming LE, Fernandez M, et al. Ciguatera Fish Poisoning: Treatment, Prevention and Management. Mar Drugs 2008; 6:456-79.

The findings and conclusions in this report are those of the author(s) and do not necessarily represent the official position of the Centers for Disease Control and Prevention or the New York City Department of Health and Mental Hygiene.