TABLE 2. Characteristics of multistate outbreaks of Listeria monocytogenes, Shiga toxin–producing Escherichia coli, and Salmonella infections, by implicated source (food, animal contact, or unknown) and pathogen — United States, 2016.
| Variable | Solved multistate outbreaks (a common food source was implicated) |
Solved multistate outbreaks (contact with a common animal was implicated as the source) |
Unsolved multistate outbreaks (common source unknown) |
All multistate outbreaks (N = 50) |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| L. monocytogenes (n = 4) | STEC (n = 5) | Salmonella (n = 19) | Total (n = 28) | Salmonella (n = 11) | Total (n = 11) | L. monocytogenes (n = 2) | STEC (n = 5) | Salmonella (n = 4) | Total (n = 11) | ||
|
Outbreak characteristic
| |||||||||||
|
Duration, days
| |||||||||||
| Median (range) duration of outbreak |
495 (152–963) |
65 (24–259) |
73 (17–218) |
81 (17–963) |
160 (36–607) |
160 (36–607) |
202 (58–345) |
22 (4–83) |
72 (18–136) |
59 (4–345) |
86 (4–963)
|
| Median (range) duration of investigation |
131 (49–207) |
39 (23–245) |
69 (25–195) |
70 (23–245) |
141 (39–512) |
141 (39–512) |
267 (95–438) |
49 (18–77) |
74 (69–79) |
70 (18–438) |
78 (18–512)
|
|
Size
| |||||||||||
| No. of cases |
39 |
102 |
515 |
656 |
1,068 |
1,068 |
43 |
70 |
87 |
200 |
1,929
|
| Median (range) per outbreak |
9 (2–19) |
11 (11–56) |
28 (6–70) |
14 (2–70) |
86 (14–248) |
86 (14–248) |
22 (5–38) |
13 (4–26) |
19 (5–45) |
16 (4–45) |
20 (2–248)
|
|
Geographic distribution
| |||||||||||
| No. of states with cases |
17 |
30 |
46 |
50 |
49 |
49 |
12 |
19 |
23 |
35 |
50
|
| Median (range) per outbreak |
6 (2–9) |
5 (2–24) |
9 (2–24) |
8 (2–24) |
25 (8–40) |
25 (8–40) |
7 (3–10) |
5 (2–14) |
7 (2–19) |
6 (2–19) |
9 (2–39)
|
|
Disposition
| |||||||||||
| Outbreak: confirmed source |
3 (75) |
3 (60) |
12 (63) |
18 (64) |
10 (91) |
10 (91) |
—* |
— |
— |
— |
28 (72)
|
| Outbreak: suspected source |
1 (25) |
2 (40) |
7 (37) |
10 (36) |
1 (9) |
1 (9) |
— |
— |
— |
— |
11 (28)
|
|
Patient characteristic
| |||||||||||
|
Age
| |||||||||||
| Median age (range), yrs |
70 (<1–91) |
20 (1–95) |
32 (<1–94) |
31 (<1–95) |
25 (<1–106) |
25 (<1–106) |
73 (29–93) |
24 (2–98) |
43 (<1–93) |
42 (<1–98) |
30 (<1–106)
|
| No. (%) of ill children aged <5 yrs |
3/38 (8) |
10/101 (10) |
53/510 (10) |
66/649 (10) |
389/1,050 (37) |
389/1,050 (37) |
3/40 (8) |
6/68 (9) |
7/86 (8) |
16/194 (8) |
388/1,898 (20)
|
| No. (%) of patients aged >65 yrs |
23/38 (61) |
9/101 (9) |
62/510 (12) |
94/649 (14) |
128/1,050 (12) |
128/1,050 (12) |
26/40 (65) |
11/68 (16) |
17/86 (20) |
54/194 (28) |
276/1,898 (15)
|
|
Sex
| |||||||||||
| Median (range) % female per outbreak |
62 (38–80) |
55 (45–77) |
64 (36–82) |
63 (36–82) |
53 (42–79) |
53 (42–79) |
34 (20–47) |
65 (50–92) |
66 (51–88) |
60 (20–92) |
59 (20–92)
|
|
Outcome
| |||||||||||
| No. of hospitalizations |
36 |
37 |
98 |
171 |
248 |
248 |
36 |
21 |
16 |
73 |
492
|
| Median (range) % hospitalized per outbreak |
100 (75–100) |
36 (18–70) |
25 (0–43) |
29 (0–100) |
28 (11–40) |
28 (11–40) |
91 (82–100) |
38 (0–77) |
29 (19–50) |
40 (0–100) |
29 (0–100)
|
| No. (range) of deaths per outbreak |
7 (1–3) |
0 |
1 |
8 (0–3) |
3 (0–2) |
3 (0–2) |
3 (1–2) |
3 (0–2) |
0 |
6 (0–2) |
17 (0–3)
|
|
Strain characteristic
| |||||||||||
| Serogroup/serotype/pathogen (no. of outbreaks caused)† | 1/2a (3) 1/2b (1) 4b (1) | O157 (4) O121 (1) O26 (1) | S. Enteritidis (4) S. Saintpaul (2) S. Typhimurium (2) S. Abony (1) S. Anatum (1) S. Braenderup (1) S. Goldcoast (1) I,4,[5],12:i:– (1) S. Javiana (1) S. Minnesota (1) S. Montevideo (1) S. Muenchen (1) S. Granienburg (1) S. Oslo (1) S. Reading (1) S. Senftenberg (1) S. Virchow (1) | S. Braenderup (2) S. Infantis (2) S. Enteritidis (1) S. Hadar (1) S. Indiana (1) S. Mbandaka (1) S. Muenster (1) S. Ohio (1) S. Poona (1) S. Pomona (1) I,4,[5],12,b– (1) Iiib 61:i:z53 (1) | 1/2b (1) 4b (1) | O157 (3) O5 (1) | S. Javiana (2) S. Bareilly (1) S. Sundsvall (1) | ||||
Abbreviations: L. monocytogenes = Listeria monocytogenes; S. = Salmonella; STEC = Shiga toxin–producing Escherichia coli.
* Not applicable.
† >1 serotype/serogroup could be included in an outbreak.