The Bureau of Epidemiology received a phone call from a Davis County resident claiming dozens of his co-workers and their children became ill after attending the book fair. Laboratory testing confirmed the presence of Salmonella enteritidis (SE) in the cases’ stool samples.

A case control study was not conducted because of the overwhelmingly significant positive association between illness and eating the Italian gelato (Italian ice-cream), the only food item served at the event. As a result of these findings, a separate investigation was undertaken to determine how the gelato may have been contaminated. An environmental health officer in Utah County conducted an interview with the caterer, whose establishment resides in that county. It was discovered that when the supply of pasteurized eggs was depleted while making the gelato, one of the employees completed the recipe using shelled eggs purchased at a nearby grocery store. Gelato samples provided by the caterer were submitted for laboratory testing but were found to be negative for SE contamination. However, the astounding numbers of symptomatic people (more than 250 individuals) and nearly 60 confirmed SE cases who attended the event, left little room for doubt as to the source of contamination.

Further investigation was undertaken to determine the source of the shelled eggs used by the caterer. The eggs were purchased by the caterer at a local grocery store, who received the product from an egg cooperative. Though the egg cooperative receives eggs from several out-of-state as well as in-state farms, the dates that the various farms supplied eggs led investigators to narrow the list down to three Utah farms and one out-of-state farm. The Utah Department of Agriculture and Food is currently working with the Utah farms to test for the presence of SE.

A number of recommendations have been made based upon the findings of this SE investigation, including:

              In commercial kitchens, pasteurized egg products should be used for all items requiring pooled eggs or raw eggs.

There were two other clusters of Utah residents running off to the doctor during the month of June, also exhibiting diarrheal illnesses. Laboratory testing confirmed the presence of S. typhimurium (ST) and S. muenchen (SM) in these cases. One cluster of ST matched a strain (through PFGE analysis) associated with the consumption of alfalfa/clover sprouts. The remaining SM cases matched a strain associated with unpasteurized orange juice contaminated with the bacteria.

On Friday, May 28, 1999 the Bureau of Epidemiology was contacted by an EIS officer from the CDC’s Foodborne Disease Division about four Utah residents diagnosed with ST. The bacteria isolated from these four cases had a PFGE pattern that was the same as that from 79 cases that were being investigated in Colorado. During the weeks that followed, three additional ST cases were identified with the same PFGE pattern. Preliminary case-control studies conducted in Colorado suggested that consumption of alfalfa/clover sprouts was associated with the disease. Five of the seven cases completed interviews with epidemiologists who inquired about the consumption and/or handling of sprouts. Despite the matching pattern among the seven cases, only two of them reported eating sprouts including an individual who grew alfalfa sprouts at his residence.

The CDC indicated that the implicated lot of clover sprouts originally came from an Oregon sprouter. This lot was then sold to distributors in Oklahoma and Kentucky. The lot was produced in November 1998 and shipped in January and February 1999. The Utah Department of Health’s Bureau of Epidemiology was particularly interested in the source of the seeds used in the home-grown sprouts, hoping to find a connection with the Oregon sprouter. A traceback including suppliers, distributors, sellers, and growers indicated this lot of seeds was originally shipped in June of 1998. The seeds were all purchased from local growers in South Dakota. From the series of phone calls, investigators learned that it was unlikely that the individual case who enjoyed home-grown sprouts became ill from them. The other case, whose PFGE pattern matched the outbreak strain, could not identify her exact date of onset due to complications from a chronic gastrointestinal disease. Although she consumes sprouts frequently from various food establishments, she also suffers from frequent abdominal pain, nausea, and vomiting. It would, therefore, be difficult to pinpoint a date for this particular traceback.

In June, unpasteurized orange juice processed from orange juice concentrate received from Mexico was implicated in cases of SM infections in Washington, Oregon, and California. Epidemiologic techniques identified the commercially distributed unpasteurized orange juice as the primary vector of these infections shortly before any Utah cases arose. As of June 25, 1999, the U.S. distributor recalled all non-pasteurized orange juice in commercial channels and halted any further distribution of the product. Nonetheless, several Utahns consumed the contaminated product before the recall. To date, seven confirmed SM cases have matched the orange juice-associated strain through PFGE analysis. The results are pending for two other SM cases. Nonetheless, eight of the nine cases have confirmed orange juice consumption during the three days prior to the onset of symptoms.

Relative to age groups, workers who were 25 - 44 years of age accounted for 60 percent of all work-related burns (Table 2). Seven percent of the work-related burns occurred among workers less than 19 years of age. Four-fifths of the injuries reported occurred in the work force less than 45 years of age. Salt Lake County accounted for 45 percent of the total workforce population and was the largest contributor to work-related burns accounting for almost two-thirds of the injuries. Approximately 22 percent of the Utah work-related burns occurred in Salt Lake City residents, 10 percent in West Valley residents and seven percent were contributed by residents of both the cities of Murray and West Jordan, respectively. These four cities in Salt Lake County accounted for almost 50 percent of all the work-related burns in Utah. Statewide, Davis (8.3), Tooele (6.8), Utah (4.5) and Weber (4.5) Counties acounted for 24 percent of the work-related burn injuries (Table 3).