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Food Poison Journal Food Poisoning Outbreaks and Litigation: Surveillance and Analysis

Is the Firefly Salmonella Outbreak 29 to 38 Times Larger than Reported?

Last week the Southern Nevada Health District identified Firefly as the source of an 86-person Salmonella outbreak in late April. [1]  In addition, three employees are also linked to the outbreak.  It is anticipated that the number of ill will rise as more people are counted from around the United States – and the world – who visited Las Vegas and dined at Firefly.

In 2009, over 40,000 cases of Salmonella (13.6 cases per 100,000 persons) were reported to the Centers for Disease Control and Prevention (CDC) by public health laboratories across the nation, representing a decrease of approximately 15% from the previous year, but a 4.2% increase since 1996. [2] Overall, the incidence of Salmonella in the United States has not significantly changed since 1996. [3]

Only a small proportion of all Salmonella infections are diagnosed and reported to health departments.  It is estimated that for every reported case, there are approximately 38.6 undiagnosed infections. [4]  More recently the CDC reported a revision of that estimate.  Now it is estimated that every year, approximately 42,000 cases of salmonellosis are reported in the United States. Because many milder cases are not diagnosed or reported, the actual number of infections may be twenty-nine or more times greater.  [5] The CDC estimates that 1.4 million cases, 15,000 hospitalizations, and 400 deaths are caused by Salmonella infections in the U.S. every year. [6, 7]

1.  Download Inspection Report and Interim Outbreak Report.

2.  CDC, “Salmonella Annual Summary Tables 2009,” 2009, available online at http://www.cdc.gov/ncezid/dfwed/PDFs/SalmonellaAnnualSummaryTables2009.pdf

3.  CDC, “Preliminary FoodNet Data on the Incidence of Infection with Pathogens Transmitted Commonly through Food—10 States, 2008,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 58, No. 14, pp. 333-37 (April 10, 2009), online at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5813a2.htm

4.  Voetsch, Andrew, et al., “FoodNet Estimate of the Burden of Illness Caused By Non-Typhoidal Salmonella Infections in the United States,” CLINICAL INFECTIOUS DISEASES, Vol. 15, No. 38, Supplement 3, pp. S127-34 (April 15, 2004) available online at http://cid.oxfordjournals.org/content/38/Supplement_3/S127.long

5.  http://www.cdc.gov/salmonella/

6.  Miller, S. and Pegues, D., “Salmonella Species, Including Salmonella Typhi,” in Mandell, Douglas, and Bennett’s PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASES, Sixth Edition, Chap. 220, pp. 2636-650 (2005).

6.  Tauxe, R, “Emerging Foodborne Diseases: An Evolving Public Health Challenge.,” EMERGING INFECTIOUS DISEASES, Vol. 3, No. 4, pp. 425-34 (1997) at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2640074/pdf/9366593.pdf