Preventive Veterinary Medicine 111 (2013) 176–180 Contents lists available at SciVerse ScienceDirect Preventive Veterinary Medicine j ourna l ho me pag e: ww w.elsevier.com/locate/prevetmed Short communication Standards for reporting surveillance information in freedom from infection models by example of Trichinella in Canadian market hogs Raphaël Vanderstichel a,* , Jette Christensen b , Henrik Stryhn a , Daniel Hurnik a a Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, Prince Edward Island, Canada C1A 4P3 b Canadian Food Inspection Agency, Epidemiology and Surveillance Section, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada C1A 4P3 a r t i c l e i n f o Article history: Received 31 October 2012 Received in revised form 21 February 2013 Accepted 24 March 2013 Keywords: Freedom from infection Surveillance Trichinella spiralis Trichinellosis Scenario tree Swine Standards a b s t r a c t Freedom from infection modeling, using scenario trees, has become an established method- ology and is well described in the literature. However, standards for organizing and reporting the surveillance information incorporated into such models are less developed. Canada has been routinely testing for Trichinella spiralis in market hogs in federally inspected slaughter plants since the late 1990s. By way of presenting our work on T. spi- ralis in Canadian hogs, we propose that information in surveillance models be organized in distinct categories, each with specific parameters and values that are thoroughly described and justified. The proposed categories are: (1) definitions for the objectives, (2) initial time period, (3) inputs, (4) data, (5) model settings, (6) outputs, and (7) validation. Having a standardized manner of reporting such studies will facilitate their validation and expedite their evaluation by experts in the field and their use in trade negotiations. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Scenario tree modeling has become an established methodology to estimate the sensitivity of a surveillance system and the probability that a population is free from a pathogen at a given level of prevalence (Martin et al., 2007). However, standards for organizing and reporting the surveillance information, incorporated in these models, are less developed. Based on our work on Trichinella spiralis, we propose that information in surveillance models be orga- nized in distinct categories, each with specific parameters and values that are thoroughly described and justified. Trichinella spp. are parasitic worms (nematodes), and the causative agent of trichinellosis, which are transmitted from ingesting meat that is contaminated with infective * Corresponding author. Tel.: +1 902 566 6006; fax: +1 902 566 0823. E-mail address: rvanderstich@upei.ca (R. Vanderstichel). larvae. Globally, the most common species of Trichinella found in domestic animals is T. spiralis, which is thought to be well adapted to pigs (Pozio and Murrell, 2006). In Canada, the last reported cases of human trichinel- losis were in 1993 and the infections were traced back to farmed wild boars raised outdoors in the province of Ontario, Canada. All of the pigs on the two affected farms were destroyed and stricter protocols for farmed wild boars were implemented (Gajadhar et al., 1997). Single cases of pig trichinellosis were found in 1990, 1993, and 1996 – all three cases originated from a small defined region in the province of Nova Scotia, also with outdoor pig production. No other cases of Trichinella species have been detected in commercial swine operations in Canada since 1980 despite regular slaughterhouse testing. Since 1998, there has been approximately 30,000 pig carcasses sampled annually in federally inspected slaughterhouses and tested by labora- tories using quality controlled and validated digestion test methods (Forbes and Gajadhar, 1999; Inch and Dore, 1999). 0167-5877/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.prevetmed.2013.03.012