BACKGROUND: Approximately 100 confirmed cases of Shiga toxin-producing E. coli (STEC) and 450 confirmed cases of salmonellosis are reported annually in Kansas. Kansas has a decentralized public health system; local health departments (LHD) have historically been responsible for interviewing all cases with a standard hypothesis-generating questionnaire. In 2016, Kansas used OutbreakNet Enhanced (OBNE) funding to implement a centralized interviewing program based on FoodCORE model practices. Centralized investigations began January 4, 2016 for salmonellosis and STEC cases that resided in the 96 of 100 LHDs that opted in to the KS-OBNE program. To evaluate the performance of KS-OBNE, timeliness and completion of case investigations were analyzed.
METHODS: Salmonellosis and STEC data for cases reported in 2012–2016 was extracted from the Kansas electronic disease surveillance system. Targets were set for the first interview attempt (3 weekdays) and investigation completion (5 weekdays) from the date of case report to public health. Data from 2016 cases was compared to data from 2012–2015 cases to measure overall statewide improvement. Confirmed cases investigated by KS-OBNE in 2016 were compared with those investigated by LHDs to measure program performance.
RESULTS: Statewide, 76% of 555 persons with confirmed salmonellosis or STEC were interviewed in 2016 compared to 69% of 2,206 cases in 2012-2015 (OR=1.4, 95%CI: 1.2-1.8). Investigations were completed within 5 weekdays for 89% of 2016 cases and 69% of 2012-2015 cases (OR=3.7, 95%CI: 2.7-5.1). Demographic and clinical information was complete for 81% of 2016 cases compared to 59% of 2012-2015 cases (OR=3.0, 95%CI: 2.3-3.9). In 2016, KS-OBNE investigated 79% of Kansas’s 555 salmonellosis and STEC cases. Interviews were completed for 82% of the 439 KS-OBNE cases compared with 54% of the 116 cases investigated by LHDs (OR=3.8, 95%CI: 2.5-5.9). Interviews were attempted within 3 weekdays for 90% of KS-OBNE cases compared with 58% of LHD cases (OR=6.4, 95%CI: 4.0-10.4). Case interviews were completed within 5 weekdays for 94% of KS-OBNE cases and 63% of LHD cases (OR=8.4, 95%CI: 4.3-16.4).
CONCLUSIONS: The implementation of centralized interviewing led to significant improvement in target measures for STEC and salmonellosis investigations in Kansas. Investigations conducted by KS-OBNE were significantly more likely to meet target measures for timeliness and completeness, highlighting the impact of centralized interviewing in Kansas. Timely and complete data collection is essential to rapid outbreak identification and efficient response. States with decentralized public health programs can benefit from implementation of centralized interviewing programs.