Survival of Murine Norovirus and Hepatitis A Virus in Different Types of Manure and Biosolids

Abstract

Noroviruses and hepatitis A virus (HAV) are common causes of foodborne disease. They are usually shed in feces and have been found in sewage water, biosolids, and animal manures. With the wide application of manure and biosolids on agricultural lands, there is an increasing interest in investigating virus survival in manure and biosolids. In this study, Murine norovirus-1 (MNV) and HAV were inoculated into different types of animal manure and three types of differently treated biosolids at 20 degrees C and 4 degrees C for up to 60 days. Both HAV and MNV viral genomes degraded immediately in high pH biosolids type 2 and 3 at time zero. For other types of manure and biosolids, HAV RNA was significantly reduced in biosolids type 1 and in liquid dairy manure (DM) after 60 days stored at 20 degrees C, but was stable in all types of manure and biosolids type 1 at 4 degrees C. MNV RNA was unstable in pelletized poultry litter and biosolids type 1 at 20 degrees C, and less stable in liquid DM at both temperatures. For MNV infectivity, there was no significant difference among pelletized poultry litter, alum-treated poultry litter, raw poultry litter, and swine manure at either 20 degrees C or 4 degrees C after 60 days of storage. However, HAV stored in swine manure and raw poultry litter had significantly higher infectivity levels than HAV stored in alum-treated poultry litter at both 20 degrees C and 4 degrees C. Overall, both viruses were inactivated rapidly in alkaline pH biosolids and unstable in liquid DM, but alum added in poultry litter had different effects on the two viruses: alum inactivated some HAV at both temperatures but had no effect on MNV.