|MO, JONGSEO - Orise Fellow|
|STEPHENS, CHRISTOPHER - Boehringer Ingelheim|
Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/9/2022
Publication Date: 4/5/2022
Citation: Mo, J., Stephens, C.B., Spackman, E. 2022. The thermal stability of Newcastle disease virus in poultry litter. Avian Diseases. 66(2):1-4. https://doi.org/10.1637/aviandiseases-D-21-00113.
Interpretive Summary: After animal disease outbreaks farms need to be cleaned and disinfected to ensure that the disease can't spread further. Disposal of bedding and other organic material is expensive and difficult because it can't be treated with a chemical disinfectant and must be carefully transported if disposal is off the farm. Here the temperature stability of a virus that causes a severe disease of poultry called Newcastle Disease virus (NDV) was characterized in used poultry litter. The goal was to determine how long the virus could survive at different temperatures so heat could be used to inactivate the virus when resources allow. Also the information could be used to help determine the risk of other disposal methods. Briefly, it was shown that the virus could remain infective from as long as112days to as little as 24hours at temperatures between 50 and 110 degrees Fahrenheit.
Technical Abstract: Sanitary disposal of contaminated organic material during recovery from an animal disease outbreak is costly and laborious. Characterizing the thermal stability of avian paramyxovirus type 1 (APMV-1; virulent APMV-1 strains cause Newcastle disease in poultry) will help inform risk assessments on the presence of viable virus on infected premises or in organic waste from infected premises. In some environments and housing types, heat may also be used as a decontamination method. Therefore, the objective of this study was to characterize the thermal stability (i.e., decimal reduction values [D values]) of APMV-1 in poultry litter. Virus inactivation was evaluated at seven temperatures from 10.0 C through 43.3 C, at 5.5 C intervals (50-110 F in 10 F intervals), using the I2 isolate of APMV-1, a vaccine strain known to be thermally stable. A high titer of virus (approximately 108 50% egg infectious doses) was added to wood shavings based, soiled chicken litter (poultry litter). Litter with both low and high moisture levels were evaluated. Samples were collected at different time intervals, and infectious virus was titrated in embryonated chicken eggs. At high temperatures (37.8 C-43.3 C), infectious virus could not be detected after 2-7 days, whereas at lower temperatures (10 C-21.1 C), it took up to 112 days for virus to decrease to undetectable levels. Furthermore, the D values were almost always shorter in the high moisture litter.