Table 1.
Gastrointestinal Outbreak and Case Characteristics in the San Francisco Bay Area, July 2003 through December 2007
| N | Outbreak-Associated Cases* | N | ||||
|---|---|---|---|---|---|---|
| Maximum | Median | Mean | ||||
| All Disease Outbreaks | 233 | 153 | 19 | 25 | Case Etiology | |
| Outbreaks of Reportable Diseases | 31 | 65 | 12 | 16 | campylobacteriosis | 3316 |
| Outbreaks of Not-Reportable Diseases | 202 | 153 | 21 | 27 | cryptosporidiosis | 2210 |
| Study Period | salmonellosis | 2187 | ||||
| Model (6/29/03 to 7/2/05)† | 71 | 110 | 15 | 23 | giardiasis | 1739 |
| Validation (7/3/05 to 12/31/05) | 11 | 26 | 14 | 13 | shigellosis | 1002 |
| Forecasting (1/1/06 to 12/30/07) | 154 | 153 | 21 | 27 | amoebiasis | 512 |
| Outbreak Etiology | hepatitis A | 152 | ||||
| norovirus | 144 | 153 | 24 | 30 | Escherichia coli infection | 151 |
| unknown | 41 | 80 | 18 | 21 | vibriosis | 118 |
| salmonellosis | 17 | 65 | 13 | 22 | typhoid | 62 |
| Bacillus cereus /Clostridium perfringens infection |
8 | 38 | 8 | 12 | listeriosis | 39 |
| Escherichia coli infection | 4 | 18 | 11 | 11 | yersiniosis | 26 |
| scombroid poisoning | 3 | 7 | 5 | 5 | legionellosis | 17 |
| bacterial toxin poisoning | 3 | 22 | 4 | 10 | ciguatera poisoning | 5 |
| chemical toxin poisoning | 2 | 4 | 3 | 3 | ||
| vibriosis | 2 | 27 | 21 | 21 | ||
| ciguatera poisoning | 2 | 3 | 3 | 3 | ||
| hepatitis A | 1 | 2 | 2 | 2 | ||
| trichinosis | 1 | 2 | 2 | 2 | ||
| cryptosporidiosis | 1 | 16 | 16 | 16 | ||
| yersiniosis | 1 | 1 | 1 | 1 | ||
| giardiasis | 1 | 14 | 14 | 14 | ||
| rotavirus | 1 | 6 | 6 | 6 | ||
| campylobacter | 1 | 3 | 3 | 3 | ||
*Number of cases not available for five outbreaks (3 salmonellosis, 2 norovirus) between January 1, 2006 and January 1, 2008.
† Modeling period was shorter --Jan 4, 2004 to Jul 2, 2005-- for Univariate Case Modeling and Cross Correlation Analysis.
σ Outbreak and case data sets are not mutually exclusive or encompassing.