National Animal Health Surveillance System Outlook
Issue 23, December 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:
- Surveillance Requirements of Cattle Fever Tick Outbreak
- Animal Disease Case Definitions to Standardize Disease Reporting
- Surveillance Widely Discussed at USAHA
- Summary of VHS Surveillance Data Analysis
NAHSS Activity Updates
- AAVLD/USAHA Forms Subcommittee on National Animal Health Surveillance
- PRV Surveillance Implementation Continues
Surveillance Requirements of Cattle Fever Tick Outbreak
Infestations of cattle fever tick in South Texas have significantly increased in recent years, from 19 recognized infested premises in fiscal year 2003 to 146 in fiscal year 2009. This increase is more than 750 percent over a 6-year time span. The last time the United States has seen this level of infestation was 36 years ago in 1973, when 170 infestations were reported. Many interlacing factors may have contributed to the current outbreak, but one factor that seems clear is the increase of white-tailed deer and corresponding decrease in cattle populations in the infested area. This, along with the interspersed additions of exotic hoof-stock in the area capable of carrying fever ticks, has demanded that the program evolve to include additional surveillance, which is critical to a successful eradication program. The government-employed mounted patrol inspectors (MPIs) provide the cornerstone of the surveillance program. The inspectors routinely perform patrols along horse trails beside the Rio Grande River, monitoring for signs of stray or smuggled livestock from Mexico that might carry fever ticks into the United States. When they discover stray or smuggled livestock, MPIs apprehend, inspect, treat, and quarantine the animals. Read the full article here.
Animal Disease Case Definitions to Standardize Disease Reporting
The National Surveillance Unit, in cooperation with the VS National Center for Animal Health Emergency Management, is currently in the process of developing animal disease case definitions and gathering input from experts across VS for use in animal health surveillance and reporting. Case definitions enhance the usefulness of animal disease data by providing uniform criteria for reporting purposes. Currently, case definitions are being developed for OIE-listed diseases and endemic diseases of interest. The case definitions under development have four intended purposes: Surveillance planning and implementation; disease background and outbreak response; National Animal Health Reporting System reporting standards; and national reportable animal disease list development. Sections include general disease/pathogen information, laboratory criteria, control and surveillance procedures, and the classification of cases. Read the full article here.
Surveillance Widely Discussed at USAHA
This year’s annual United States Animal Health Association (USAHA) meeting in San Diego included many discussions about animal health surveillance issues. Various committees discussed surveillance, specifically: H1N1 surveillance in several committee meetings; pseudorabies and classical swine fever in the Transmissible Diseases of Swine Committee; changes to the bovine brucellosis and tuberculosis programs and related surveillance modifications in respective committees and subcommittees; national animal health surveillance and reporting systems in the AAVLD/USAHA joint Animal Health Surveillance and Information Committee; contagious equine metritis and equine piroplasmosis outbreaks and resultant surveillance in the Committee on Infectious Diseases of Horses; global surveillance methodology in various committee meetings; vector-borne and emerging disease surveillance in the joint USAHA-AAVLD plenary session and VS’ 2015 session with a breakout group specifically discussing Surveillance for Action. Read more about surveillance discussions at USAHA here.
Summary of VHS Surveillance Data Analysis
Viral hemorrhagic septicemia (VHS) is an OIE-listed disease. Through APHIS-VS cooperative agreement funding starting in 2007, State and Tribal Nations conducted surveillance for viral hemorrhagic septicemia virus (VHSV) IVb in the regulated area--defined by jurisdictional boundaries of the eight Great Lakes States. VHSV risk evaluations devised by expert panel were also distributed to State Area Veterinarians-In-Charge and aquaculture liaisons for voluntary assessment. In the fall of 2009, the VS-CEAH National Surveillance Unit analyzed results from the first 2 years of cooperative agreement surveillance and risk evaluation data. Efforts to demonstrate disease freedom were initiated in 12 States outside the Great Lakes and also in non-affected portions of States within the regulated area. Risk evaluations were completed in 13 States. Here is a report on the VHS surveillance analysis.