National Animal Health Surveillance System Outlook
Issue 22, July 2009
The NAHSS Outlook is an electronic communication with information about the National Animal Health Surveillance System (NAHSS) that is distributed via email to all members of Veterinary Services. Contact the National Surveillance Unit to provide comments and suggestions for future topics.
Articles in This Issue:
- Livestock disease surveillance at auction markets
- Expert opinion used to characterize potential CSF outbreak
- VS develops, implements swine influenza virus (SIV) surveillance plan
- NAHMS program continues to provide information to decisionmakers
NAHSS Activity Updates
- OIE producing surveillance handbook
- Vesicular stomatitis, equine arboviral Web reporting begins
- Meeting focuses on future of national TB program
Livestock disease surveillance at auction markets
Auction markets serve as important transaction channels for beef cattle, dairy cattle, sheep, and swine. These animals can potentially be relocated into other livestock populations or sent directly to slaughter. Markets, therefore, may serve as useful locations for conducting surveillance. To better characterize the numbers, origin, and destination of animals traversing auction markets, a Colorado State University research team conducted a study as part of a cooperative agreement with APHIS-VS. In that study, the research team demonstrated that fence line observation could be used to obtain relevant health data on livestock entering an auction market. However, the ability of such a surveillance system to detect particular diseases is a necessary focus for further research, as is establishing baseline observation rates for these or other syndromes during different times of year and across multiple auction markets. In a continuation of the study, the team is currently measuring the inter-observer variation among laypersons (first-year veterinary students) conducting fence line observation at a Colorado auction market. More on the auction market surveillance study.
Expert opinion used to characterize potential CSF outbreak
The National Surveillance Unit (NSU) recently incorporated the use of expert-opinion methodology to characterize the biological consequences of a classical swine fever (CSF) outbreak in U.S. commercial swine. NSU assembled and interviewed the panel of 18 experts regarding the characteristics and consequences of an outbreak both in the presence and in the absence of current surveillance activities, and under the present swine production system and veterinary diagnostic laboratory testing structure. Opinions from the expert panel were compiled statistically to capture not only the most frequent answers, but also the less frequent opinions, which were used to represent the variability around central values. Results were incorporated into a disease spread model to characterize the magnitude of a potential CSF outbreak under the conditions recommended by the experts. Output from the disease spread model was used to estimate vaccine requirements for the National Veterinary Stockpile in the event of a CSF outbreak in commercial swine in Iowa and North Carolina. Read more here.
VS develops, implements swine influenza virus (SIV) surveillance plan
Veterinary Services has developed and implemented a surveillance plan for swine influenza virus (SIV), including the pandemic H1N1 (pH1N1) 2009 flu outbreak virus, in swine. The plan is based on the most current information available on this novel influenza virus strain. Surveillance is aimed to identify the pH1N1 strain as well as other non-typical strains of SIV in swine. The immediate goals of the surveillance program are to: determine if the pH1N1 flu outbreak virus currently exists in U.S. swine; if the virus is present, determine the distribution to inform further policy decisions; detect novel influenza virus strains in swine in a timely manner; and determine genetic characteristics of novel viruses necessary for vaccine and diagnostics development. The surveillance plan will allow for the differentiation of novel influenza virus strains from other circulating endemic strains of SIV. Read more about SIV surveillance.
NAHMS program continues to provide information to decisionmakers
Since the inception of the National Animal Health Monitoring System (NAHMS) program in 1989, its goal has been to provide timely information to decisionmakers in the stakeholder community. This includes a wide range of interested parties—from regulators and legislators to individual producers and consumers—making it a challenge to have “the right information at the right time.” However, NAHMS’ continuous information-needs assessment process addresses these issues by gathering new information and by using historical data compiled during previous national studies and other targeted investigations. Recent inquiries have included requests for information about antimicrobial use/resistance, spread model parameterization, and animal disease traceability. Read more about the NAHMS program.