Enteric Virus Indicators: Reovirus Versus Poliovirus

The resistance of reovirus to inactivation by mesophillic and thermophillic temperatures was investigated and compared to existing inactivation patterns for poliovirus, the most commonly used enteric virus indicator. The resistance of reovirus to alkaline condition resulting from the addition of lime (CaO) to biosolids was also examined. Phase one involved the incubation of reovirus in a buffered solution for a 28-day period at different temperatures ranging from 4  to  50°C. This phase also involved reovirus incubation at thermophillic temperatures ranging from 50  to  55°C for a 30min period. The second phase looked at reovirus survival in biosolids mixed with lime doses ranging from 0  to  100  g lime per kg dry biosolids over a 23-day period. Reovirus was more resistant to inactivation caused by longterm storage under mesophillic temperature conditions than poliovirus. Reovirus also was more resistant to inactivation caused by short-term storage under thermophillic temperature conditions than poliovirus. Reovirus has shown to be stable in biosolids under naturally occurring environmental conditions for up to 1  year, while doses of 80  g lime per kg dry biosolids and greater were able to meet class A levels for enteric viruses after 1  day of storage.