Layout 1 ISDS Annual Conference Proceedings 2012. This is an Open Access article distributed under the terms of the Creative Commons Attribution- Noncommercial 3.0 Unported License (http://creativecommons.org/licenses/by-nc/3.0/), permitting all non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ISDS 2012 Conference Abstracts Detection of a Swine Erysipelas Outbreak Using Enhanced Passive Surveillance Judy Akkina*1, Wolf Weber1 and Lisa Becton2 1USDA, APHIS, Veterinary Services, Fort Collins, CO, USA; 2National Pork Board, Des Moines, IA, USA Objective To describe detection and response for an erysipelas outbreak in market swine in the United States (U.S.) using Food Safety and In- spection Service (FSIS) slaughter condemnation data, and coordina- tion with the swine industry in an Enhanced Passive Surveillance (EPS) pilot project. Introduction EPS is a comprehensive effort to complement other types of sur- veillance and provide early detection and situational awareness of significant endemic, zoonotic, and emerging diseases of livestock. The concept for EPS involves gathering syndromic and observational data from multiple animal health surveillance sources, including pri- vate practitioners, livestock markets, livestock harvest facilities, and veterinary diagnostic laboratories. A signal indicating a potential an- imal health event in one data stream can be corroborated in the other streams. For swine surveillance in the U.S., USDA-APHIS monitors the number of swine condemned for specific reasons. Likewise, in- dustry practitioners share front-line clinical information within their practitioner network to detect anomalies. This case summary demon- strates the successful outcome of implementing an EPS pilot program through Federal and industry partnership. Methods FSIS Animal Disposition Reporting System swine condemnation data are monitored by USDA-APHIS Veterinary Services (VS) for several condemn conditions, including erysipelas, a bacterial disease of swine. Typically, slaughter condemnations for erysipelas are rare. The monitored data represent 83 market swine harvest facilities throughout the U.S. A modification of the ‘C3’CUSUM aberration detection method from the Early Aberration Reporting System (EARS) is applied to the data at both the slaughter plant level and at a larger multi-plant swine catchment basin level which represents separate swine production areas. The National Pork Board (NPB), a U.S. swine producer association, hosts a quarterly conference call with a sentinel network of swine veterinarians to exchange informa- tion about anomalies in swine health observed by practitioners. Dur- ing mid-February 2012, several practitioners suspected a local increase in erysipelas in finishing swine. Absent baseline data on erysipelas occurrence nationally, the scope of the problem was un- certain. Following the call, the NPB in collaboration with VS at- tempted to validate the information reported by swine practitioners. Results Beginning the week of January 8, 2012, VS analysts noted a slight increase in erysipelas CUSUM signaling activity in the greater Iowa catchment basin slaughter plants. During the seven-week period be- tween January 8 and February 25, eight weekly plant-level CUSUM signals were observed, while the previous 36-week period yielded only fourteen plant-level signals. On average, 0.39 signals per week were noted in the weeks prior to the outbreak period while the corre- sponding average for the seven-week outbreak period was 1.14 plant signals per week. Seven of the eight plants that signaled during the outbreak period did not report large weekly spikes; however, the weekly accumulation of condemns were sufficient to trigger concern. Since the erysipelas signals were not large compared to the back- ground noise, there was uncertainty whether the increased signaling activity truly represented a disease event. After cross validating the slaughter surveillance data with front line practitioner information, a swine health alert regarding the increase in erysipelas cases was is- sued by the American Association of Swine Veterinarians. Interven- tion measures were initiated as deemed appropriate by each private veterinarian. Conclusions This example of an Enhanced Passive Surveillance Program demonstrates use of independent streams of information from gov- ernment and private industry to detect an outbreak of erysipelas in market swine. The communication process was facilitated by the NPB and the American Association of Swine Veterinarians, and co- ordinated with the industry resulting in an appropriate response to prevent swine losses at very early stages of the outbreak. Corrobora- tion and validation between the two data streams (slaughter and prac- titioner) provided confidence that an outbreak was beginning and assisted the swine industry in decision making to enhance disease prevention activities. This type of early warning and response can re- duce the cost of disease outbreaks to swine producers as well as pro- vide confidence in the national disease status for swine in the United States. Keywords animal health surveillance; Federal and industry partnership; en- hanced passive surveillance; swine erysipelas *Judy Akkina E-mail: judy.e.akkina@aphis.usda.gov Online Journal of Public Health Informatics * ISSN 1947-2579 * http://ojphi.org * 5(1):e44, 2013