Infectious laryngotracheitis vaccine virus detection in water lines and effectiveness of sanitizers for inactivating the virus.

摘要

A commercial infectious laryngotracheitis virus (ILTV) chicken embryo-derived (CEO) vaccine was isolated in chicken embryos after the vaccine had attached to the biofilm from drinking water systems. The CEO vaccine was transmitted to chickens from 14 to 21 d after the vaccine was added to the water systems. Real-time quantitative PCR was used to detect ILTV DNA in water systems containing the biofilm and in the trachea of birds that drank from the water systems. Two commonly used inexpensive water sanitizers, citric acid and sodium hypochlorite, did not remove the biofilm and inactivate the live ILTV CEO vaccine in the water lines. When the water systems were treated with 2 other commercial sanitizers (sodium bisulfate and hydrogen peroxide), the ILTV vaccine was not reisolated from the water lines or tracheal samples. However, some water and tracheal swabs were positive for ILTV DNA by real-time quantitative PCR. Water lines in chicken houses that have received an ILTV CEO vaccine may be an important source for reinfection of newly placed flocks. Therefore, these water systems need to be treated with an appropriate biofilm-reducing sanitizer to prevent the reinfection of subsequent chicken flocks with vaccine-derived viruses.