Prevention of Listeriosis Outbreaks in a High-Risk

Food Service Setting

How can an RD help?

Presented by Anne Smith

What is Listeriosis?

A foodborne illness caused by ingesting the bacteria Listeria monocytogenes

Gram-positive bacillus

Found in water and soil, non-pasteurized milk and milk products, and on contaminated vegetation

Can also be found in infected animals who ingested the bacteria

Cold-tolerant; can survive and replicate in temperatures below 40oF

Can colonize on environmental surfaces

Can easily be killed by heat

L. monocytogenes Gram-positive bacillus

Who is at Risk?Pregnant women and the fetus

Highest risk in third trimester Can cause spontaneous abortion

Immunocompromised persons Malignancies Solid organ and bone marrow transplantations Immunosuppressive therapy- HIV infection and AIDS

Neonates

Older adults

Kidney or liver disease

Alcoholism

Diabetic patients

Symptoms

Febrile gastroenteritisMost common in healthy adults

Mild, flu-like symptoms

Fever, intense headaches, nausea, and vomiting

Bacteremia and meningitisMost common in Immunocompromised

Miscarriage, stillbirth, premature delivery, or life-threatening infections in a newborn

9%-30% can be fatal

What foods can be affected?

Cold ready-to-eat foods not heated before consumptionDelicatessen-style meats, hotdogsCold-prepared salads such as tuna salad or egg

saladSoft cheeses- feta, Brie, Camembert, blue-veined

cheeses, or Mexican-style cheeses such as queso blanco, queso fresco and Panela

Contaminated vegetables and animal products

Risk increases for durations of refrigeration

CDC Reported Outbreaks2011- Listeriosis Linked to Whole Cantaloupes

from Jensen Farms, Colorado

2012- Listeriosis Linked to Imported Ricotta Cheese

2013- Listeriosis Linked to Crave Brother Farmstead Cheese

http://www.cdc.gov/listeria/outbreaks/index.html

Global Reported Outbreaks

US- 175 cases reported in 3 yearsAbout 58/yr

Globally in 2006France- 290Germany- 508UK- 208Spain- 78Czech Republic- 78Netherlands- 64

Occurrences of Listeriosis in Healthcare

Fall 2003, UK 5 pregnant women 2 separate facilites Contaminated sandwiches

February 2010, Texas 10 cases in 7 months 5 separate facilities Contaminated diced celery

September 22, 2008, New York 3 listeriosis cases at hospital X 2 other cases identified later Contaminated tuna salad

How is it identified?

Pulsed-field gel electrophoresis (PFGE) patterns

Our study

Serving High-Risk Foods in a High-Risk Setting:

Survey of Hospital Food Service Practices after an Outbreak of Listeriosis in a

Hospital

Carolyn Cokes, MPH, Anne Marie France, PhD, Vasudha Reddy, MPH, Heather Hanson, MPH, Lillian Lee, MS, Laura Kornstein, PhD,

Faina Stavinsky, MS, Sharon Balter, MD

Purpose

“This report summarizes the outbreak investigation for Listeriosis in a NYC hospital as well as the results of a

telephone survey of NYC hospitals that explored risk management practices for foodborne illnesses in hospital settings.”

5 cases of Listeriosis were reported from Hospital X in New York

Subjects

4 male, 1 female

Median age was 62 years (range 52-92 yo)

All had medical conditions that put them at high-risk of ListeriosisComplications from transplanted liverChiari syndromeChronic heart failureMitral valve disorder

Methods

5 Methods of InvestigationEpidemiologic InvestigationEnvironmental InvestigationLaboratory InvestigationHospital SurveyStatistical Methods

Epidemiologic Investigation

Medical record abstractions

Patient interviews Onset dates Clinical illness Food history

Menus from hospital cafeteria

Reports posted to identify other related Listeriosis cases CDC’s Epi-X communication site PulseNet CDC Team electronic bulletin board

Environmental Investigation

9/23/08-Full sanitary inspection- NYC OEI Swabs of food-contact surfaces

9/25/08- HACCP analysis based on prep reviews Tuna salad and turkey sandwiches

9/29/08- Samples collected Environmental surface samples for Listerosis analysis

9/30/08 and 10/3/08- More samples 25 samples from cooking/storage surfaces, kitchen

equipment, vents, drains, and floors 20 food samples- tuna, chicken, and egg salad

Laboratory Investigation

Clinical isolates from NYC cases submitted to PHL for analysis

All samples were analyzed for PFGE patterns

L. monocytogenes DNA was restricted using 2 enzymes Ascl and Apal

Gels were uploaded to PulseNet for identification of related cases

Hospital Survey

Section 1

Director of Infection Control

Prevalence of high-risk patients in comparison to total patients

Units available for high risk patients

Section 2

Food Service Director

Focus on foods served

Food service practices and policies

Policies restricting service of items that present high risk

61 acute care hospitals in NYC were asked to participate in a telephone survey, 54 responded

January-April 2009

Statistical Methods

SAS software, version 9.1 SAS Institute

P values 2-sidedCalculated by Fisher exact test, x2 analysis or t test

Epidemiologic Results

Food historiesPts 1-3 obtained by direct interviewPt 4- no history, patient diedPt 5- partial history from next of kin

Common foods- Tuna salad and sliced turkeyPts 1-3- reported having bothPt 5- most likely consumed both

Hospital did not keep copies of food orders

None of the 5 patients have been in rooms on the same floor at the same time

Laboratory Results

Contaminated samples 4 samples of tuna salad1 can-opener sample 1 floor drain sample

All 5 human isolates contained L. monocytogenes

No similar PFGE patterns were in PulseNet

PFGE

Environmental Results

Inspections showed no violations of NYC health codes

HACCP investigation showed tuna was held at 41oF for 4 days before being served

2 environmental samples contained L. monocytogenesCan opener base- opened the cansFloor drain- located near 100 qt mixer

October 2009- all negative samples

9 were public hospitals, 45 were private hospitals

23 reported maintaining patient food orders

8 kept records with patient charts

29 reported outside food vendor contracts

Survey Results

Food Safety Practices"Despite the potential for severe outcomes of Listeria infection among hospitalized patients,

the majority of NYC hospitals that participated in the food practice survey had no food

preparation policies or practices to minimize risk for L. monocytogenes contamination." 

Foodborne Illness Risk Management Guidelines

Reported Raw fruits and vegetable use

•62% of Large hospitals reported not using raw F&V

•Facilities with transplant pts less likely to report use of raw F&V

• 75% with bone marrow transplant units

• 100% with organ transplant units

Helpful PoliciesFrom the study:

Steam deli meats before servingDo not serve soft cheesesUse only cooked (irradiated) F&V components

Other Suggestions:Severely limit storage time of high-risk foodsKeep better food records for healthcare providersRoutine and thorough cleaning of food surfacesKeep records of patient food orders and diet

historyTest strips? Contract out food service?

Role of the RD

Menu planning

Food purchasing planning, budgeting, and source approval

Education of food service workers on food safety

Daily/weekly dietary assessments of high-risk patients

Eurosurveillance- improve procedures

Computer system to track orders

Global Food Safety

Global Food Safety InitiativeManufacturers

ServSafe certificationsCostly?

Australia’s Food Safety GuidelinesSafer food alternatives

Food Standards Agency –UKVideo learning

Comments

Stacy- “Do you think it is the role of the RD or DTR to monitor patient charts to prevent them from receiving potentially dangerous foods?  Listeria outbreaks are preventable with proper food safety practices, so do you believe better training of kitchen staff is more important than monitoring food ordered?”

Liz- “A computer based diet record and food ordering system should have flags that prevent at-risk persons of ordering risky items off the menu.  I know its possible to flag for such things as a "heart healthy diet" or "diabetic diet", why not create another category for "at-risk".  

Other Comments?

References Cokes, Carolyn, MPH, Anne Marie France, PhD, Vasudha Reddy, MPH, Heather Hanson, MPH, Lillian

Lee, MS, Laura Kornstein, PhD, Faina Stavinsky, MS, Sharon Balter, MD. “Serving High-Risk Foods in a High-Risk Setting: Survey of Hospital Food Service Practices after an Outbreak of Listeriosis in a Hospital.” Infection Control and Hospital Epidemiology. April 2011. Vol 32 No 4

Denny, Justin, Jim McLauchlin. “Human Listeria monocytogenes infections in Europe - an opportunity for improved European surveillance.” EUROSURVEILLANCE Vol. 13 · Issues 1–3 · Jan–Mar 2008.

http://www.health.ny.gov/diseases/communicable/listeriosis/fact_sheet.htm. Accessed online September 5, 2013.

http://www.cdc.gov/listeria/index.html. Accessed online September 5, 2013.

Dawson, SJ, MR Evans, D Willby, J Bardwell, N Chamberlain, DA Lewis. “Listeria outbreak associated with sandwich consumption from a hospital retail shop, United Kingdom.” Eurosurveillance, Volume 11, Issue 6, 01 June 2006.

Gaul, Linda Knudson, Noha Farag, Trudi Shim, Monica Kingsley, Benjamin Silk, Eija Hyytia-Trees. “Hospital-Acquired Listeriosis Outbreak Caused by Contaminated Diced Celery—Texas, 2010”. Clin Infect Dis. (2013) 56 (1): 20-26

http://www.food.gov.uk/. Accessed online September 9, 2013.

http://www.health.sa.gov.au/pehs/food-index.htm. Accessed online September 9, 2013.