Skip to main content
ARS Home » Southeast Area » Auburn, Alabama » Aquatic Animal Health Research » Research » Publications at this Location » Publication #243755

Title: Determining and mitigating risks of disease introduction

Author
item Karreman, Grace
item Klotins, Kim
item Innes, Paul
item Kebus, Myron
item Bebak, Julie
item Osborn, Andrea
item Gustafson, Lori
item Tiwari, Ashwani

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/12/2009
Publication Date: 8/17/2009
Citation: Karreman, G.A., Klotins, K., Innes, P., Kebus, M., Bebak, J., Osborn, A., Gustafson, L., Tiwari, A. 2009. Determining and mitigating risks of disease introduction. International Aquatic Biosecurity Conference. Trondheim, Norway. August 17-18,2009.

Interpretive Summary:

Technical Abstract: Biosecurity can be defined as a system of processes (i.e., inputs, movements and other activities), each with a set of procedures, that taken together minimize the risk of introduction and spread of infectious organisms within or between aquatic animal populations. Biosecurity measures at the site level include bioexclusion (prevention of pathogens from entry), within-site infectious disease control (management of pathogens within a facility) and biocontainment (prevention of pathogens from release). This presentation will focus on bioexclusion of pathogens/diseases from commercial aquaculture facilities. Viral hemorrhagic septicaemia virus (VHSV) in salmonid species will be used as an example. Although HACCP or HAACP-like analyses have been used to look at biosecurity measures in aquatic facilities, HACCP is designed to identify risks of contamination by food-borne pathogens and to institute measures to keep levels below scientifically justifiable critical limits. Infectious disease control, which focuses on disease freedom and negligible risk of tranferring pathogens that replicate within a host to produce disease, relies on risk assessment that identifies mitigation points and mitigation measures intended to reduce risk to neglible in aquatic animal populations. A new model needs to be developed that incorporates both infectious disease control principles and the monitoring and verification steps from HAACP. A risk assessment can estimate the risks of introducing pathogenic organisms or disease into an aquatic animal site and provide recommendations for mitigation of the risks. Components of an introduction risk assessment include hazard identification (i.e., diseases of concern), hazard characterization (presentation of the appraised science, the susceptible species list and information for mitigation measures) and estimation of the likelihood of introduction of each identified hazard given the introduction scenario (in this case, it is assumed the consequences are similar for each hazard). Sources of disease introduction include aquatic animals, water, fomites, vectors and feed. An on-site analysis provides the scenario for pathogen introduction into the site. There must be a working understanding of the production biology of the species, the physical layout of the facility and the process flow for operations. Specific points of pathogen introduction can be identified by systematically evaluating every step in the process flow for potential inputs of the pathogen into the site, by: • Infected or exposed live animals • Contaminated water • Contaminated vectors • Contaminated fomites • Contaminated feed The mitigation measures in place to reduce the risk to negligible should also be identified. There are approximately 20 generic types of mitigation measures applicable to potential introductions though animals, water, vectors, fomites and feed. Gaps where mitigation measures should be in place are also identified. A documented biosecurity plan is the only way of demonstrating that disease control is happening without an ongoing effective testing plan. After the risk assessment is complete, the site can produce a biosecurity plan outlining the identified points of pathogen introduction and the mitigation measures to reduce the risk of introduction to negligible. The plan includes the production biology of the species, the physical layout of the facilities and the process flow for operations. Standard operating procedures (SOP’s) are developed for each of the mitigation measures using a standardized format. The plan includes all records necessary to document the appropriate implementation of the mitigation measures. The plan also includes quality control checklists to record verification that the mitigation measures are being followed. Plans are typically reviewed once yearly to incorporate physical, biological, and oper