Epidemiologic and surveillance studies on avian influenza in live-bird markets in New York and New Jersey, 2001

Abstract

In 2001, all 109 retail live-bird markets (LBMs) in New York and New Jersey were surveyed for the presence of avian influenza virus (AIV) by a real time reverse transcriptase/polymer chain reaction assay (RRT/PCR) and results compared to virus isolation (VI) in embryonating chicken eggs. The RRT/PCR had a 91.9% sensitivity and 97.9% specificity in detecting presence of AIV at the market level. However, the sensitivity at the sample level is 65.87%. The RRT/PCR is a reliable method to identify AIV at the market level. In addition, a cross-sectional epidemiologic study of the LBMs showed that, during the past 12 months, markets that were open 7 days per week and those that also sold rabbits had the highest risk for being positive for AIV. Markets that were closed one or more days per week and those that performed daily cleaning and disinfecting had the lowest risk for being AIV positive.