Table 1.
Milk used to make cheese
|
||
---|---|---|
Unpasteurized | Pasteurized | |
Outbreaks, no. | 38 | 44 |
Illnesses, no. | 816 | 987 |
Hospitalizations, no. | 168 | 61 |
Deaths, no. | 3 | 3 |
| ||
Etiology | N = 38 n (%) | N = 33 n (%) |
| ||
Salmonellab | 13 (34) | 6 (18) |
Campylobacter | 10 (26) | 1 (3) |
Brucella | 5 (13) | 0 (0) |
Shiga toxin–producing Escherichia colic | 4 (11) | 1 (3) |
Listeria monocytogenes | 4 (11) | 8 (24) |
Shigella | 2 (5) | 1 (3) |
Bacillus cereus | 0 (0) | 1 (3) |
Norovirus | 0 (0) | 13 (39) |
Other virus | 0 (0) | 1 (3) |
Staphylococcus aureus | 0 (0) | 1 (3) |
| ||
Cheese source or setting of preparation | N = 34 n (%) | N = 44 n (%) |
| ||
Imported from Mexico | 13 (38) | 0 (0) |
Private home | 7 (21) | 4 (14) |
Dairy or farm | 7 (21) | 3 (7) |
Restaurant, deli, or banquet | 1 (3) | 28 (64) |
Commercial product without further preparation | 1 (3) | 7 (16) |
Otherd | 5 (15) | 2 (5) |
An additional 8 outbreaks with 79 illnesses, 1 hospitalization, and no deaths in which the pasteurization status was unknown were reported.
Salmonella serotypes in outbreaks due to cheese made from unpasteurized milk were Typhimurium (6 outbreaks), Newport (2 outbreaks), Bovismorbificans (1 outbreak), Meleagridis and Newport (1 outbreak), serotyping only identified Group B (1 outbreak), not reported (2 outbreaks). Salmonella serotypes in outbreaks due to cheese made from pasteurized milk were Montevideo (2 outbreaks), Java, Newport, Typhimurium (1 outbreak each), not reported (1 outbreak).
All 4 outbreaks due to cheese made from unpasteurized milk were caused by E. coli O157:H7. Three non-O157 Shiga toxin–producing E. coli serogroups were isolated in the outbreak due to cheese made from pasteurized milk.
Other settings for outbreaks with cheese made from unpasteurized milk were street vendor (2 outbreaks), grocery store (2 outbreaks), and fair or festival (1 outbreak). For pasteurized cheeses: grocery store (1 outbreak) and school (1 outbreak).