Foodborne Outbreak Surveillance and Investigations in California Akiko Kimura, MD Medical Epidemiologist California Department of Public Health Symposium on Food Systems & Public Health May 17, 2013

Annual Burden of Food-Related Illness in the U.S. 48 million illnesses (1 in 6 people!) 128,000 hospitalizations 3,000 deaths

CA Enteric Disease Surveillance CA surveillance system is decentralized CA population: 38 million 61 local health jurisdictions (LHJs) CDPH involved if multiple jurisdictions involved, media interest, or if consultation requested Most intense follow-up done for Salmonella, Shiga-toxin producing E. coli, and Listeria Majority sporadic cases Most investigations done by LHJs

Foodborne Outbreak Detection Foodborne Outbreak Detection Foodborne outbreak: 2 or more people ill with GI illness after consuming the same food Local Health Jurisdiction – Customer complaint lines – Foodborne illness/outbreak reports – Laboratory reports, PFGE CA Department of Public Health – Reports from LHJs – Bacterial serotyping – Pulsed-field gel electrophoresis (PFGE) Genetic fingerprinting database for bacterial pathogens

Foodborne Outbreak Scenarios e.g., church picnic, wedding banquet e.g., E. coli in spinach, Salmonella in peanut butter Traditional ScenarioNewer Scenario acute and highly local usually event associated, or affects a discrete population; “point-source” high inoculum, high attack rate cases don’t know each other, looks like sporadic cases diffuse and widespread outbreak low-level contamination of widely distributed food product

Outbreak Investigations Highlights Campylobacter associated with raw milk E. coli O157 H7 associated with romaine lettuce Listeria monocytogenes associated with ricotta salata cheese Vibrio parahemolyticus associated with oysters Salmonella Agona, Derby and Infantis associated with pork Salmonella Agona associated with papaya Salmonella Bareilly associated with tuna “scrape” Salmonella Bredeney associated with peanut butter Salmonella Braenderup associated with mangoes

Rachael Joseph, VMD, MPH Epidemic Intelligence Service Officer, County of San Diego Health and Human Services Agency, Division of Global Migration and Quarantine, CDC Investigation of a Multi-State Outbreak of Salmonella Braenderup— California, July–September, 2012 Office of Surveillance, Epidemiology, and Laboratory Services Scientific Education and Professional Development Program Office

Outbreak Detection 10 th 20 th July 1 st August 10 th August 3, 2012: CA Microbial Diseases Laboratory (MDL) identifies cluster (N=14) 14 cases S.Braenderup August 8 : CDC names cluster “1208CAJBP-1” (N=27)

EPIDEMIOLOGICAL Interview of cases, hypothesis generation, analytical study Methods LABORATORY Testing of human and environmental isolates ENVIRONMENTAL Trace back investigation, inspection of source

Initial Descriptive Epidemiology (N=35 as of 8/12)  12 LHJs  Median age 28 years (range: 1 – 86 yrs)  93% Hispanic; 62% Female  Potential risk factors:  24/29 fresh fruits  24/30 fresh vegetables  Mostly shopped at small markets

Hypothesis Generating  Standardized questionnaire  Both closed and open-ended questions  >100 exposures  Ethnic foods (spices, meats, produce)  14 interviews conducted 8/15 – 8/19  Early signal for mangoes Canada reports cluster of S. Braenderup seemingly associated with mangoes HGQ

Matched Case Control Study  Purpose: Test hypothesis that mangoes or another food exposure identified in HGQs was associated with illness  Case: CA patient with outbreak strain of S Branederup  Control: Age, ethnicity, and geographically matched persons recruited from existing Salmonella database  Telephone interviews in English or Spanish between August 22 – 23, 2012 HGQ N=57

Percent of Cases and Controls Matched By Age Group and Ethnicity with Specific Food Exposures—S.Braenderup, 1208CAJBP-1 CASES CONTROLS Food AteTotal Ate TotalAte Matched Odds Ratio Exact p-value Watermelon203754%184639% Strawberries203754%284661% Mango % % Lettuce163743%224549% Tomato213757%314569% Mango was the only food exposure significantly associated with illness.

Traceback  Conducted by FDB A Food and Drug Branch (FDB) in coordination with FDA  Mangoes traced back to a single mango exporter, Agricola Daniella, of Sinaloa, MX  Multiple farms supply mangoes  One packing plant in Sinaloa

Mango Health Alerts and Recalls  8/24 – Canadian Food Inspection Agency issued a Health Hazard Alert for mangoes sold by North American Produce Sales  8/29 – Splendid Products of Burlingame, CA voluntarily recalled Daniella brand mangoes sold on 7/12 – 8/29  8/29 – CDPH issued a press release warning consumers against eating Daniella-Brand Mangoes  9/9 – FDA placed import alert on mango supplier, Agricola Daniella of Sinaloa, MX

S.Braenderup 1208JBP-1 Case Counts by State (N=121 as of 9/13/2012)

Conclusions  Large multi-state, multi-national outbreak of S. Braenderup  ~80% of U.S. cases occurred in CA  Mostly among Hispanic females  Mango was the only food exposure significantly associated with illness in a matched case-control study  Traceback investigation implicated a single exporter in Mexico as the source of mangoes consumed by cases  Investigation resulted in voluntary mango recalls and an import alert by FDA

Questions?