Volume 7, Number 7—June 2001
Research
A One-Year Study of Foodborne Illnesses in the Municipality of Uppsala, Sweden
, Yvonne Andersson†, Johan Lindbäck†, Maria Wegscheider‡, Yvonne Eriksson‡, Lasse Tideström§, Angela Lagerqvist-Widh¶, Kjell-Olof Hedlund†, Sven Löfdahl†, Lennart Svensson†, and Anna Norinder#
Table 2
Disease agents detected in feces and food samples and implicateda as etiologic agents in the investigated illnesses
| Detected in
(no. samples/incidents) |
Implicated in (no.) |
|||
|---|---|---|---|---|
| Feces | Food | Incidents | Illnesses | |
| Bacteria | ||||
| Bacillus cereus | nab | 12/9 | 3 | 5 |
| Campylobacter spp. | 12/12 | 0 | 12 | 16 |
| EHECb | 4/4c | 5/5d | 3 | 4 |
| EIECb | 1/1 | na | 1 | 1 |
| EPECb | 1/11 | na | 1 | 2 |
| ETECb | 1/1c | na | 0 | 0 |
| Salmonella spp.e | 1/1 | 0 | 1 | 1 |
| Staphylococcus aureus | na | 10/9 | 5 | 99f |
| Total | 20/20 | 25/21c | 26 | 128 |
| Viruses | ||||
| Astroviruses | 2/2 | na | 2 | 2 |
| Caliciviruses | 25/23c | na | 20 | 41 |
| Rotaviruses | 3/3c | na | 2 | 2 |
| Total | 29/27c | 24 | 45 | |
| Histamine | na | na | 2 | 3 |
| Several agents | c | 3 | 5 | |
| Unknown | 213 | 334 | ||
| Negative | 76/56 | 133/45 | ||
| Total agents | 123/101g | 158/66 | 268 | 515 |
aThe agent was implicated as a cause of an illness incident on the basis of laboratory evidence, the interview, and assuming foodborne transmission.
bna = not analyzed; EHEC = enterohaemorrhagic Escherichia coli; EIEC = enteroinvasive E. coli; EPEC = enteropathogenic E. coli; ETEC = enterotoxigenic E. coli.
cIn two of the incidents, two (caliciviruses and EHEC) and three agents (calicivirus, ETEC, and rotaviruses), respectively, were detected in feces samples, and in two other incidents, two agents (E. coli and B. cereus, and S. aureus and B. cereus, respectively) were detected in food samples.
dRefers ti generic E. coli. No further characterization was done.
eSalmonella Enteritidis (phage type 21).
fIn the largest incident (93 cases), disease agents other than S. aureus may have been involved since atypically long incubation times were recorded for some of the cases.
gSum minus negative does not equal the number of positive samples since two or more agents were detected in some samples. See footnote c.