Transcript Dr. Patricia Griffin

Progress and challenges
in decreasing foodborne illnesses
in the United States
Patricia M. Griffin, M.D.
Chief, Enteric Diseases Epidemiology Branch
Division of Foodborne, Bacterial and Mycotic Diseases
National Center for Zoonotic, Vectorborne and Enteric Diseases
April 12, 2008 Who’s Minding the Store? Seattle, Washington
Foodborne illnesses United States
 Estimates for 1997
• 76 million ill
• 300,000 hospitalized
• 5,000 deaths
 Healthy People 2010 targets:
50% reduction (from 1997 to 2010) in
• E. coli O157
• Campylobacter
• Salmonella
• Listeria
Mead et al., EID 5:707-25, 1999
Major known foodborne pathogens, 2008
 Bacteria
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Bacillus cereus
Brucella
Campylobacter
Clostridium botulinum
Clostridium perfringens
E. coli O157
E. coli, non-O157 Shiga toxin-producing
E. coli, other diarrheagenic
Listeria monocytogenes
Mycobacterium bovis
Salmonella Typhi
Salmonella non-typhoidal
Shigella
Staphylococcus
Streptococcus
Vibrio cholerae, toxigenic
Vibrio vulnificus

Bacteria (continued)
• Vibrio, other
• Yersinia enterocolitica
• Yersinia pseudotuberculosis
 Parasites
• Cryptosporidium
• Cyclospora
• Giardia
• Toxoplasma
• Trichinella
• Trypanosoma cruzii
 Virus
• Caliciviruses
• Rotavirus
• Astrovirus
• Hepatitis A
• Hepatitis E
• Prions
 Fungus
• Aflatoxin-producing
Major known foodborne pathogens, 2008
 Bacteria
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Bacillus cereus
Brucella
Campylobacter
Clostridium botulinum
Clostridium perfringens
E. coli O157
E. coli, non-O157 Shiga toxin-producing
E. coli, other diarrheagenic
Listeria monocytogenes
Mycobacterium bovis
Salmonella Typhi
Salmonella non-typhoidal
Shigella
Staphylococcus
Streptococcus
Vibrio cholerae, toxigenic
Vibrio vulnificus

Bacteria (continued)
• Vibrio, other
• Yersinia enterocolitica
• Yersinia pseudotuberculosis
 Parasites
• Cryptosporidium
• Cyclospora
• Giardia
• Toxoplasma
• Trichinella
• Trypanosoma cruzii
 Virus
• Caliciviruses
• Rotavirus
• Astrovirus
• Hepatitis A
• Hepatitis E
• Prions
 Fungus
• Aflatoxin-producing
* Green = recognized as foodborne in past 30 years
Major identified foodborne pathogens, 2008
 Bacteria
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•
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•
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Bacillus cereus
Brucella
Campylobacter*
Clostridium botulinum
Clostridium perfringens
E. coli O157*
E. coli, non-O157 Shiga toxin-producing*
E. coli, other diarrheagenic*
Listeria monocytogenes*
Mycobacterium bovis
Salmonella Typhi
Salmonella non-typhoidal
Shigella
Staphylococcus
Streptococcus
Vibrio cholerae, toxigenic*
Vibrio vulnificus*

Bacteria (continued)
• Vibrio, other*
• Yersinia enterocolitica*
• Yersinia pseudotuberculosis*
 Parasites
• Cryptosporidium*
• Cyclospora*
• Giardia*
• Toxoplasma*
• Trichinella
• Trypanosoma cruzii*
 Virus
• Caliciviruses*
• Rotavirus*
• Astrovirus*
• Hepatitis A
• Hepatitis E*
• Prions*
 Fungus
• Aflatoxin*
Yellow = “Home” of organism is the animal kingdom
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
FoodNet Sites, 2008
Population 45.5 million (15% of U.S. population)
FoodNet
 Although all 50 states conduct surveillance for
foodborne pathogens,
• methods and data quality vary
 Need accurate counts of illnesses to measure trends
 FoodNet sites have extra resources
• to get reports from clinical labs when ill people
submit a specimen (usually stool) for testing, and
• to submit those reports to CDC
 FoodNet measures trends in common foodborne
pathogens
• Issues an annual “report card”
(MMWR April 11, 2008)
Surveillance data
 Surveillance data is the
“tip of the iceberg”
Pyramid of Surveillance
Reported to health department
Pathogen isolated
Lab tests for pathogen
Specimen obtained
Person seeks care
Person becomes ill
Population exposed
Pyramid of Surveillance
Reported to health department
Pathogen isolated
Active surveillance
Lab tests for pathogen
Clinical lab survey
Specimen obtained
Person seeks care
Person becomes ill
Population exposed
}
Population survey
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Sequence of events in E. coli O157 infection
E. coli O157 ingested
3 - 4 days
non-bloody diarrhea, abdominal cramps
80%
1 - 2 days
bloody diarrhea
92%
resolution
Mead. Lancet 1998
5-6
days
8%
HUS
Hemolytic uremic syndrome (HUS)
 Kidney failure, anemia, blood clotting
problems
 Affects persons of all ages
• most common in <5 years old and elderly
 ~5% die
E. coli O157 infections, incidence by year, FoodNet, 1996-2007
Healthy People 2010 Objective: 1.0 illness/100,000 persons
Incidence per 100,000 population
3
2.5
2
0.90
1.5
1.20
1
National objective
0.5
0
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Year
Percent of USDA ground beef samples that yielded
E. coli O157:H7, 2000-2007
Outbreak investigation resulted in recall of
18 million pounds ground beef
% positive
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
2000
2001
Source: www.fsis.usda.gov
2002
2003
2004
2005
2006
2007
E. coli O157 infections, incidence by year, FoodNet, 1996-2007
Healthy People 2010 Objective: 1.0 illness/100,000 persons
Incidence per 100,000 population
3
2.5
2
0.90
1.5
1.20
1
National objective
0.5
0
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Year
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Campylobacter
 Common cause of foodborne illness
• diarrhea
• paralysis is rare complication
 Most illnesses from chicken
• that is undercooked, or
• that contaminates other foods
Campylobacter infections, incidence by year, FoodNet, 1996-2007
Healthy People 2010 Objective: 12.30 illnesses/100,000 persons
Incidence per 100,000 population
30
25
20
12.78
15
10
National objective
5
0
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Year
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Salmonella
 Common cause of foodborne illness
• diarrhea
• severe illness in vulnerable populations
 Carried by all food animals
 Foodborne illness mainly from
• foods of animal origin
• vegetables contaminated with fecal matter from
animals
Salmonella infections, incidence by year , FoodNet, 1996-2007
Healthy People 2010 Objective: 6.8 illnesses/100,000 persons
Incidence per 100,000 population
18
16
14.92
14
12
10
8
6
National objective
4
2
0
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Year
Percent change in the incidence of bacterial infections in 2007compared with the
previous 3 years (2004-2006), FoodNet
100
Percent change estimate
95% confidence interval
80
Percent change
Increase
60
40
20
No change
0
-20
-40
Decrease
-60
-80
-100
Campylobacter
Listeria
Salmonella
Shigella
STEC*O157
Graph Interpretation
No significant change = The 95% confidence interval is both above and below the “no change” line
Significant increase = The estimate and the entire 95% confidence interval are ABOVE the “no change” line
Significant decrease = The estimate and the entire 95% confidence interval are BELOW the “no change” line
Vibrio
Yersinia
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
PulseNet USA
 National network of >75 public health and regulatory laboratories
 Perform molecular typing of foodborne disease-causing bacteria
• current method is pulsed-field gel electrophoresis (PFGE)
• create DNA “fingerprints”
 Share DNA “fingerprints” electronically
 DNA “fingerprints” are sent to database at CDC
• Reviewed daily at CDC
• available on-demand to participants
PulseNet searches for clusters
•State health departments
submit patterns
electronically
•CDC and State labs search
for similar patterns in past
2-4 months
•compare patterns
visually
•When cluster identified,
PulseNet contacts
epidemiologists
Cluster of indistinguishable patterns
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
CDC OutbreakNet Team
 Supports a national network of epidemiologists and
other public health officials who investigate
outbreaks of foodborne, waterborne, and other
enteric illnesses in the United States
 Mission
• Ensure rapid, coordinated detection & response to multistate enteric disease outbreaks
• Promotes comprehensive outbreak surveillance
CDC OutbreakNet Team (continued)
 Works in partnership with PulseNet
 Involves collaborations between CDC and
• State and local health departments
• U.S. Department of Agriculture (USDA) Food Safety and
Inspection Service (FSIS)
• U.S. Food and Drug Administration (FDA)
Outbreaks
 Outbreaks that we find and
solve are the
“tip of the iceberg”
 We investigate outbreaks
• To take immediate action
to protect people
• To learn how to prevent
similar occurrences
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Lettuce at Mexicanstyle fast food chain
Snack food with vegetable coating
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Increase in Salmonella Tennessee illnesses
 August to December 2006
• gradual increase in ill persons over expected
number
 December 2006
• epidemiologists interviewed some ill persons
• found no common exposures
States where patients with the outbreak strain of
Salmonella Tennessee lived
(as of December 1, 2006)
PulseNet found more than the expected number of
this strain of Salmonella
States where patients with the outbreak strain of
Salmonella Tennessee lived
(as of December 1, 2006)
PulseNet found more than the expected number of
this strain of Salmonella
Most states had only 1-2 ill persons
Illnesses continued to increase
 January 2007
• interviewed 31 ill persons with long questionnaire
• consumed peanut butter and turkey more often than general population
• Interviewed 6 people with open-ended questions
• suspected a brand of peanut butter
 February 2007
• designed questionnaire focusing on peanut butter (brand,
quantity)
• interviewed ill and well persons
• peanut butter statistically linked to illness
– only Brands A and B
Actions
 February 13, 2007
• notified Food and Drug Administration (FDA)
• found that brands A and B produced at same plant
• distributed to 50 states and ~70 countries
 Next day
• plant ceased all production
 Voluntary recall of all products
Peanut butter testing after recall
 35 jars (opened and unopened) yielded outbreak strain
Investigation of plant
 Two environmental samples yielded outbreak strain
 Leaky roof and faulty sprinkler in summer
• timing coincided with start of outbreak
• moisture in processing plants favors growth of
Salmonella
Persons with Salmonella Tennessee infection,
by onset week, August 2006 – July 2007
Product Recall:
(N=532)
February 14, 2007
Contaminated jars produced
July 2006 – January 2007
Number of Cases
40
35
30
25
20
15
10
5
0
7 /2 3
Aug
2006
Sep
Oct
Nov
Dec Jan
Feb
Mar
2007
Week illness began
Apr
May
Jun
Jul
Persons with Salmonella Tennessee infection,
by state, August 2006 – July 2007
(N=714 persons ill)
None
1–9
10 – 19
≥ 20
Summary of peanut butter outbreak
 Diffuse national outbreak
• Detected by routine Salmonella surveillance, enhanced by
PulseNet subtyping
 Required intensive multi-state investigation
 First U.S. outbreak linked to peanut butter
 Product recall based on epidemiologic findings
 Contamination at plant over many months
Points out the importance of controlling contamination
in processed ready-to-eat foods
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Attribution project
 How much foodborne illness is from each food
commodity, e.g., beef, eggs, vegetables?
 Using outbreak data to make estimates
 Preliminary data indicates that more illnesses due to
known pathogens are acquired by consuming
vegetables than any other commodity
• leafy greens an important concern
Outbreaks caused by leafy greens,1973–2006
(N=219)
Spinach 3%
Broccoli 1%
Fresh herbs 8%
Cabbage 22%
Lettuce 66%
Herman, Lynch, CDC, unpublished
Proportion of outbreaks due to
consumpton of leafy greens, 1981–2005
% of outbreaks
10%
8%
6%
4%
2%
0%
1981-1985
1986-1990
Denominator is outbreaks with known food vehicle
1991-1995
1996-2000
2001-2005
Year
Source: USDA/Economic Research Service. Data last updated Feb. 15, 2007.http://www.ers.usda.gov/Data/FoodConsumption/FoodAvailSpreadsheets.htm
Topics
 National networks
• National surveillance
• FoodNet
•
•
•
•
Overview
E. coli O157
Campylobacter
Salmonella
• PulseNet
• OutbreakNet
• Overview
• Some recent outbreaks
• Example: Salmonella outbreak
 Attribution project
 Progress and challenges
Progress in the past 10 years
 Much better systems for detecting and
investigating foodborne illnesses
• FoodNet
• PulseNet
• OutbreakNet
 Declines in incidence of several pathogens, e.g.,
• E. coli o157
• Campylobacter
Progress in the past 10 years (continued)
 Improved safety of some foods, e.g.,
• ground beef less contaminated
• fewer outbreaks from shell eggs
• fewer outbreaks from juice
• increased attention to ready-to-eat foods, e.g.,
peanut butter
 Developing methods to attribute foodborne
illnesses to food commodities
Some of the challenges
 Salmonella infections have not decreased
• widespread in food animals
 Campylobacter from live chickens contaminates
retail chicken
 Complex ecologies in farming areas link food
animals with vegetable fields
• food animal manure contaminates
vegetables consumed raw
Foodborne diseases in the 21st century
Attention to ecologies of foodborne agents
 Many foodborne agents live in animals’ intestines
 Many foodborne agents can survive in outdoor environments
and processing plants
 Food safety needs to be an integral part of farming practice
Food concerns, e.g.,
 Produce consumed raw
 Processed foods, e.g., peanut butter, pot pies, snacks
 New food products and processes every year
pic
Foodborne diseases in the 21st century
(continued)
More diffuse, multi-state and multi-national outbreaks
Strong public health capacity for surveillance and response
needed to
 identify problems
 assure that knowledge of safety gaps from outbreak
investigations are applied throughout industry
The fall and rise of Salmonella infections,
United States, 1920-2004
Incidence per 100,000 population
Typhoid fever
50
45
40
35
30
25
20
15
10
5
0
1920
Non-typhoid salmonellosis
Increasing contamination of
food and water with animal
manure
Prevented contamination
of food and water with
human sewage
Challenge: provide safe
feed and water to food
animals and plants
?
1930
1940
1950
1960
Years
CDC, National Notifiable Diseases Surveillance data
1970
1980
1990
2000
Acknowledgments
State and Local Health
Departments & Public Health Laboratories
Alabama
Louisiana
North Dakota
Alaska
Maine
Ohio
Arizona
Maryland
Oklahoma
Arkansas
Massachusetts
Oregon
California
Michigan
Pennsylvania
Colorado
Minnesota
Rhode Island
Connecticut
Mississippi
South Carolina
Delaware
Missouri
South Dakota
Florida
Montana
Tennessee
Georgia
Nebraska
Texas
Idaho
Nevada
Virginia
Illinois
New Hampshire
Vermont
Indiana
New Jersey
Washington
Iowa
New Mexico
Wisconsin
Kansas
New York
West Virginia
Kentucky
North Carolina
Wyoming
The findings and conclusions in this presentation are those of the author(s) and do not necessarily represent the views of the
Centers for Disease Control and Prevention.
Acknowledgments (continued)
Major CDC contributors to
peanut butter investigation
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Tracy Ayers
Cheryl Bopp
Gwen Ewald
Peter Gerner-Smidt
Olga Henao
Mike Hoekstra
Mike Lynch
Manoj Menon
Laura Moyer
Thai-An Nguyen
Katherine Niksich
Nehal Patel
Nancy Puhr
Anandi Sheth
Samir Sodha
Kathleen Wannemuehler
Other major CDC contributors
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Fred Angulo
Christopher Braden
Patricia M. Griffin
Karen Herman
John Painter
Anandi Sheth
Robert V. Tauxe
Ian Williams
FDA
USDA
The conclusions and opinions expressed herein are those of the presenter and do not
necessarily represent the views or policies of CDC or DHHS
Our websites
FoodNet:
http://www.cdc.gov/foodnet
PulseNet:
http://www.cdc.gov/pulsenet
Foodborne outbreak surveillance:
http://www.cdc.gov/foodborneoutbreaks
CDC Safe Water System:
http://www.cdc.gov/safewater
General Information About Diseases:
http://www.cdc.gov/health
Thank you
The findings and conclusions in this presentation are
those of the author and do not necessarily represent the
views of the Centers for Disease Control and
Prevention