Bureau of Epidemiology
Bureau of Epidemiology July 1999 Utah Department of Health
inside...
Salmonella . . . Just Another Gastric Monstrosity!
Hepatitis A:   Testing of the Acutely Ill Patient
Work-Related Burn Surveillance in Utah, 1997
Monthly Morbidity Summary
 

Salmonella . . . Just Another Gastric Monstrosity!

It was an unusually cold and rainy summer’s day in June when a large Salt Lake County employer held a book fair for their employees’ children. The young ones probably ran up to the ice cream vendor to get their pick between chocolate, strawberry, or vanilla Italian gelato. Consequently, many of the events’ attendees were running off to the doctor in the days that followed, complaining of severe diarrhea, abdominal pain, and fever.

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.

Traceback of eggs implicated in SE outbreaks should be conducted to the individual farm level. If a farm is found to be infected with SE, appropriate control measures should be implemented immediately. In addition, an effort should be made to determine the method by which SE was introduced into the farm ecosystem in order to prevent future propagation of the contaminant.

Commercial food establishments should work to identify and eliminate practices conducive to cross-contamination.

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.

It is hopeful that through the cooperative efforts of the state and local health departments, the Utah Department of Agriculture and Food, the Utah poultry industry and commercial food establishments, that these outbreaks can be controlled. Medical doctors can assist in this effort by maintaining a high level of suspicion of salmonella in patients presenting with diarrhea and fever. Stool cultures should be performed and positive test results should be promptly reported to state or local health department officials.

Return to Index

Hepatitis A: Testing of the Acutely Ill Patient

Recently the Bureau of Epidemiology received several hepatitis A reports on patients positive for hepatitis A total antibody. This type of result indicates that a person has been infected with hepatitis A at some point in time. It is, however, impossible to tell from this type of result, whether or not a person is acutely ill with hepatitis A. For this purpose, it is necessary to test a person for hepatitis A antibody IgM. For most laboratories it is standard protocol to follow up any positive total antibody result with an IgM antibody test. Other laboratories will only run an IgM antibody test if it is specifically ordered by the healthcare provider. It is recommended that any provider ordering an acute hepatitis panel on a patient, verify what tests will actually be run, and if necessary, specify that an IgM antibody test be run for hepatitis A.

Return to Index

 

Work-Related Burn Surveillance In Utah, 1997

Work-related burns are the leading cause of injury in the United States. Approximately 1.4 million persons in the United States sustain burns each year, of which approximately 54,000 to 84,000 are hospitalized. In Utah, 10,352 work-related burns (thermal and chemical) were reported to the Industrial Accident Division of the Utah Labor Commission between 1992 and 1995. Approximately 20 percent of all serious burns in Utah requiring hospitalization were work-related during this time period.

In 1997, the Environmental Epidemiology Program of the Utah Department of Health received a grant from the Centers for Disease Control and Prevention, National Institute of Occupational Safety and Health (NIOSH) to develop and maintain a registry of work-related burn cases in Utah, and to use the information from cases to develop and implement intervention activities. Interventions include education and consultation to employees where burn hazards occur, education for cases and workers, broader industry-wide studies, and research.

The Environmental Epidemiology Program examined the incidence of hospital admissions attributed to work-related burns that occurred in the state of Utah in 1997 through the review of hospital discharge data. This data was received by the Utah Department of Health, Bureau of Epidemiology under the authority of the Utah Injury Reporting Rule (R386-703). During 1997, hospitals throughout Utah reported 699 hospital admissions that were attributed to burns. Of these reported burn-related injuries, 133 cases were occupationally-related and 436 were non-occupational. In addition, there were three mortality cases attributed to work-related burns. Records were also abstracted when necessary and each record was reviewed to eliminate duplications.

The results of this evaluation suggest that the incidence for work-related burns was significantly higher among males than females. Of the 133 work-related burn injuries reported, males accounted for 82 percent of the injuries in contrast to females who accounted for 18 percent of the injuries (Table 1).

Table1. Crude incidence rates of occupational (Occ.) burn injury cases, total number of occupational burns, total number of burns, and percent of total number of occupational burns in Utah by sex during 1997.

BURN INJURIES IN UTAH BY SEX, 1997

SEX

INCIDENCE OF OCC. BURNS

TOTAL NO. OF OCC. BURNS

TOTAL

NO. OF BURNS

% FROM TOTAL NO. OF OCC. BURNS

FEMALE

5.3

24

148

18.0

MALE

*19.6

109

288

82.0

BOTH SEXES

13.2

133**

436**

100.0

†Crude incidence rates are calculated per 100,000 population based on Utah’s 1997 total workforce population.
*Statistically significantly different from female rates.
Data Source: Burn injury data was obtained from the Utah Department of Health, Bureau of Epidemiology from Databases of Hospital Admissions and Discharge Data under the authority of the Utah Injury Reporting Rule (R386-703).
**There is a variation in agreement of data sets between total number of cases by age group and total number of cases by county and by sex due to incomplete records for the selection criteria.

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).

Table 2. Crude incidence rates of occupational (Occ.) burn injury cases, total number of occupational burns, total number of burns, and percent of total number of burns in Utah by age-specific groups during 1997.

BURN INJURIES IN UTAH BY AGE GROUPS, 1997

1997

AGE GROUP

INCIDENCE OF OCC. BURNS

TOTAL NO. OF OCC. BURNS

TOTAL

NO. OF BURNS

PERCENT

OF ALL

OCC. BURNS

15 - 19

10.6

10

49

7.6

20 - 24

9.8

15

46

11.4

25 - 34

16.3

39

99

29.5

35 - 44

16.3

40

104

30.3

45 - 54

10.2

18

60

13.6

55 - 64

9.5

7

35

5.3

65 +

12.0

3

40

2.3

All Groups

13.2

132*

433*

100.0

†Age-specific crude incidence rates are calculated per 100,000 population based on Utah’s age-specific total workforce population for 1997. Data Source: Burn injury data was obtained from the Utah Department of Health, Bureau of Epidemiology from Databases of Hospital Admissions and Discharge Data under the authority of the Utah Injury Reporting Rule (R386-703).
* There is a variation in agreement of data sets between total number of cases by age group and total number of cases by county and by sex due to incomplete records for the selection criteria.

 

Table 3. Crude incidence (Inc.) rates of occupational (Occ.) burn injury cases, total number of occupational burns, total number of burns, and percent of total number of burns in Utah by county during 1997.

BURN INJURIES IN UTAH BY COUNTY, 1997

COUNTY

Inc.

of Occ. Burns

No.

of Occ. Burns

Total

No. of Burns

% of All Occ. Burns

COUNTY

Inc.

of Occ. Burns

No.

of Occ. Burns

Total

No. of Burns

% of

All Occ. Burns

Beaver

0.0

0

0

0.0

Piute

0.0

0

0

0.0

Box Elder

5.7

1

1

0.8

Rich

226.2

2

2

1.5

Cache

0.0

0

11

0.0

Salt Lake

18.6

84

262

63.2

Carbon

11.2

1

4

0.8

San Juan

0.0

0

2

0.0

Daggett

0.0

0

0

0.0

Sanpete

12.7

1

2

0.8

Davis

10.4

11

29

8.3

Sevier

0.0

0

4

0.0

Duchesne

37.3

2

4

1.5

Summit

8.0

1

7

0.8

Emery

52.4

2

4

1.5

Tooele

81.7

9

23

6.8

Garfield

0.0

0

0

0.0

Uintah

41.1

4

10

3.0

Grand

20.9

1

2

0.8

Utah

4.0

6

24

4.5

Iron

7.4

1

2

0.8

Wasatch

0.0

0

1

0.0

Juab

0.0

0

1

0.0

Wash.

3.0

1

6

0.8

Kane

0.0

0

1

0.0

Wayne

0.0

0

0

0.0

Millard

0.0

0

2

0.0

Weber

6.6

6

32

4.5

Morgan

0.0

0

0

0.0

State of Utah

13.2

133*

436*

100.0

†Crude incidence rates are calculated per 100,000 population based on specific county’s 1997 total workforce population. Data Source: Burn injury data was obtained from the Utah Department of Health, Bureau of Epidemiology from Databases of Hospital Admissions and Discharge Data under the authority of the Utah Injury Reporting Rule (R386-703).
* There is a variation in agreement of data sets between total number of cases by age group and total number of cases by county and by sex due to incomplete records for the selection criteria.

Return to Index

Utah Department of Health, Bureau of Epidemiology
Monthly Morbidity Summary
- July 1999 - Provisional
Data

wpe1.gif (16655 bytes)

The Epidemiology Newsletter is published monthly by the Utah Department of Health, Division of Epidemiology and Laboratory Services, Bureau of Epidemiology, to disseminate epidemiologic information to the health care professional and the general public.

Send comments to:  The Bureau of Epidemiology. Box 142104, Salt Lake City, UT 84114-2104, or call (801) 538-6191
Approval 8000008:  Appropriation 3705

Rod Betit, Executive Director, Utah Department of Health
Charles Brokopp, Dr.P.H., Division of Epidemiology and Laboratory Services
Craig R Nichols, MPA, Editor, State Epidemiologist, Director Bureau of Epidemiology
Cristie Chesler, BA, Managing Editor

Return to Index