CDC OutbreakNet Enhanced 2020 Cumulative Metrics Data: Salmonella, Shiga Toxin–producing Escherichia coli, Listeria, Shigella, and Campylobacter [SSL(SC)]

Report Period: [January 1, 2020] to [December 31, 2020]

Table showing 2020 cumulative metrics data
SSL(SC) Performance Metrics:
(See associated document for complete language and definitions)
Salmonella Measures
Mean (Range)
STEC¹ Measures
Mean (Range)
Listeria Measures
Mean (Range)
Shigella Measures²
Mean (Range)
Campylobacter Measures² Mean (Range)
1a. Total number of SSL(SC) isolates and isolate-yielding specimens submitted to or recovered at the Public Health Lab (PHL) 872 (64 – 3,592) 151 (5 – 657) 17 (0 –51) 131 (0 – 932) 146 (1 – 682)
1b. Number of SSL(SC) primary isolates or isolate-yielding specimens 790 (60 – 3,305) 124 (3 – 585) 15 (0 – 42) 125 (0 – 909) 119 (1 – 662)
2a. Total number of preliminary positive SSL(SC) clinical specimens or samples received at PHL (regardless of if isolate-yielding or not) 494 (6 – 1,594) 210 (3 – 654) 9 (0 – 51) 76 (1 – 255) 135 (0 – 660)
2b. Total number and percent of isolate-yielding SSL(SC) clinical specimens or samples received at PHL 422 (6 – 1,299); 84.9% (25.4% – 100%) 110 (3 – 346); 56.1% (31.1% – 100%) 9 (0 – 51); 84.2% (0% – 100%) 45 (0 – 243); 52.7% (0% – 100%) 72 (0 – 442); 63.3% (0% – 100%)
3a. OPTIONAL: Percent of SSL(SC) primary isolates with PFGE testing at PHL 14.1% (0% – 14.1%) 2.1% (0% – 15%) No cumulative data available 3.1% (0% – 24.6%) No cumulative data available
3b. Percent of SSL(SC) primary isolates with WGS testing at PHL 89% (13% – 100%) 83.9% (3% – 100%) 80.8% (0% – 100%) 30.7% (0% – 100%) 34.1% (0% – 100%)
4a. OPTIONAL: Median time from SSL(SC) isolate receipt (or recovery) at PHL or PFGE request to pattern upload to PulseNet No cumulative data available No cumulative data available No cumulative data available No cumulative data available No cumulative data available
4b. Median time from SSL(SC) isolate receipt (or recovery) at PHL or WGS request to sequence upload to PulseNet 9.4 (4 – 20) days 9.2 (4.3 – 20) days 7.7 (3 – 31) days 12.1 (0 – 25) days 6.1 (0 – 14)
5a. Total number of SSL(SC) cases reported to public health 1,029 (35 – 6,600) 219 (8 – 1,066) 24 (0 – 211) 246 (1 – 1,664) 1,191 (43 – 5,900)
5ai. OPTIONAL: Percent of SSL(SC) cases with isolates and isolate- yielding specimens submitted to PHL 84.3% (56% – 100%) 66.9% (35% – 90.7%) 83.5% (50% – 100%) 55.3% (3.7% – 93.8%) 28.12% (0.2% – 64%)
5b. Total number of laboratory confirmed SSL(SC) cases reported to epidemiology staff 875.2 (24 – 5,889) 97 (4 – 570) 16 (0 – 63) 142.92 (0 – 1,037) 624 (19 – 4,178)
5c. Total number of probable SSL(SC) cases reported to epidemiology staff 152.3 (1 – 711) 103 (0 –430) 1 (0 –4) 104 (0 – 663) 565 (0 – 2,156)
5d. Total number of suspect SSL(SC) cases reported to epidemiology staff N/A 17 (0 – 69) .25 (0 – 2) N/A N/A
6a. Percent of SSL(SC) cases with attempted interview 83.2% (3.7% – 100%) 87.8% (59.9% – 100%) 87.8% (50% – 100%) 76.7% (0% – 100%) 71.7% (8.7% – 100%)
6ai. Percent of laboratory confirmed cases with attempted interview 82.7% (4.5% – 100%) 87.4% (33% – 100%) 89.8% (50% – 100%) 68.4% (0% – 100%) 72.6% (8.3% – 100%)
6aii. Percent of probable cases with attempted interview 81.9% (1.9% – 100%) 91.6% (69.2% – 100%) No cumulative data available 72.6% (0% – 100%) 71.3% (5% – 100%)
6aiii. Percent of suspect cases with attempted interview N/A 56.4% (0% – 100%) N/A N/A N/A
6b. Median time from SSL(SC) case report to initial interview attempt 3.5 (< 0 – 12) days 3.1 (<1 – 20.4) days 1.9 (<1 – 13) days 8.4 (<1 – 97) days 4.5 (<1 – 15) days
6c. Percent of SSL(SC) cases with exposure history obtained 68.9% (10.7% – 99.2%) 77% (18.1% – 100%) 80.9% (45.5% – 100%) 64.5% (0% – 93%) 63% (20.5% – 88.9%)
6ci. OPTIONAL: Among SSL(SC) cases with an exposure history, percent with full shotgun or case exposure completed 65.3% (16% – 98.6%) 55.9% (0% – 98.6%) 95.3% (62.9% – 100%) 65.5% (0% – 100%) 66.7% (0% – 100%)
6cii. OPTIONAL: Time from case report to when an exposure history is obtained. 5.7 (2 – 12) days 12 (2-85) days 4.5 (1-10) days 5.6 (2-12) days 6 (3 -12) days
7. Number of SSL(SC) clusters 1.7 (0– 15) 7.1 (0 –31) 2.4 (0 – 25) 2.4 (0 – 29) 0.9 (0 -8)
8a. OPTIONAL: Total number and percent of SSL(SC) clusters with routine interview of cases3 1.7 (1 – 10); 83.3% (0% – 100%) 7.8 (1 – 31); 95.7% (62.5% – 100%) 2.6 (0 – 12); 93.5% (54.5% – 100%) 1 (0 – 2); 87.5% (50% – 100%) 1 (0 – 2); 100%
8b.Total number and percent of SSL(SC) clusters where an analytic epidemiologic study was conducted3 0.5 (0 – 4); 40.9% (0% – 100%) 1.9 (0 –12); 37.7% (0% – 100%) 1.1 (0 –6); 53.1% (0% – 100%) No cumulative data available 0.4 (0 – 2); 55% (0% – 100%)
9a. Total number and percent of SSL(SC) clusters with confirmed vehicle/source identified3 0.4 (0 – 2); 25.5% (0% – 100%) 2.0 (0 – 11); 22.2% (0% – 50%) 0.6 (0 –4); 21.6% (0% – 100%) 0.5 (0 – 3); 22.8% (0% – 100%) 0.3 (0 – 1); 50% (0% – 100%)
9b. OPTIONAL: Total number and percent of SSL(SC) clusters with suspect vehicle/source identified3 0.1 (0-1); 20% (0%-100%) 1.3 (0-5); 17.2% (0%-50%) 1 (0-4); 41.7% (0%-100%) 0.5 (0 – 1); 100% 1 (0-4); 75% (50% – 100%)
10. Total number and percent of SSL(SC) clusters where food or environmental sample collected for testing3 .5 (0 – 2); 31.6% (0% – 100%) 1.7 (0 – 5); 23.6% (0% – 100%) 0.6 (0 – 2); 35.8% (0% – 100%) No cumulative data available 0.2 (0 – 1); 38% (0% – 100%)
11. Total number and percent of SSL(SC) clusters where environmental health, agriculture, regulatory, or food safety program staff were contacted3 4.1 (0 – 22); 42.4% (0% – 100%) 7.0 (0 – 41); 54.1% (0% – 100%) 1.7 (0 – 15); 73.1% (0% – 100%) 0.5 (0 – 4); 56.7% (0% – 100%) 0.6 (0 – 2); 82.6% (13% – 100%)
12a.Total number of SSL(SC) outbreaks, excluding multi-state outbreaks 1.0 (0-3) 3.4 (0-32) No cumulative data available 0.5 (0-4) 0.6 (0 – 7)
12b.Total number and percent of SSL(SC) outbreaks, excluding multi-state outbreaks, reported/submitted to NORS 0.7 (0 – 2): 91.7% (50% – 100%) 2.2 (0 – 11); 77.9% (0% – 100%) No cumulative data available 1.7 (1 – 3); 100% 1.5 (0 – 6); 95.3% (86% – 100%)

All data are cumulative. Data are only reported when available from 5 or more sites.
1Shiga Toxin-producing Escherichia coli
2Reporting is optional for Shigella and Campylobacter
3This metric is calculated for only those sites that reported having clusters in Metric 7