Design of Infectious Disease Surveillance in Swine

• Activity Number: 507
• Type: Contributed
• Date/Time: Wednesday, August 1, 2012 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistical Consulting
• Author(s): Chong Wang*+
• Companies: Iowa State University
• Keywords: sequential ; disease diagnostic testing ; test frequency ; imperfect test

Abstract

Clinical outbreaks of animal infectious diseases have made the U.S. and the world industry suffer greatly. For example, the pork industry alone has lately witnessed disease outbreaks involving porcine reproductive and respiratory syndrome (PRRS) virus, porcine circovirus type 2 (PCV2), torque teno virus (TTV), porcine parvovirus infection (PPV), etc. A pivotal part of disease surveillance is the sequential disease diagnostic testing, which establishes patterns of disease prevalence progression for the study population. In design of sequential diagnostic testing, two questions have to be answered: 1. How many animals need to be tested? and 2. How often does the testing need to be done? We construct statistical models which relate sampling size and frequency to the time of detection after disease outbreak. Out model allow the diagnostic test used to be impact, ie, the sensitivity and specificity of tests could be less than 1. The sampling scheme depends on the type of farm, the performance of diagnostic tests, the prevalence of outbreak, and the desired power and time of detection after potential outbreak.