Publication Abstract

Disinfection of Feline Calicivirus, (a surrogate for novovirus) in waste waters

J.A. Tree, M.R. Adams and D.N. Lees

Norovirus (NV, previously termed Norwalk-like virus (NLV) is a member of the family Caliciviridae and known to be an important cause of human waterborne disease. Little is known about the survival of this virus following wastewater disinfection because NV viability cannot be assayed by normal virus culture methods. In this study a comparison was made between the inactivation of a bacterial water quality indicator, Escherichia coli; a culturable human enteric virus, poliovirus; a viral indicator, FRNA bacteriophage (MS2); and feline calicivirus (FCV), a culturable surrogate for NV. Bench-scale disinfection experiments used wastewater (sterilised by gamma irradiation) seeded with monodispersed laboratory cultured organisms exposed to disinfectants. Seeded primary effluent was treated with different doses of applied free chlorine (8, 16 and 30 mg/l). FCV and E. coli were easily inactivated by > 4 log_10, within the first 5 min with a dose of 30 mg/l of applied free chlorine. Poliovirus was more resistant and a reduction of 2.85 log₁₀ was seen after 30 min contact time. MS2 was the most resistant organism with only 1 log₁₀ inactivation after 30 min contact time with 30mg/l of applied free chlorine. In further experiments seeded secondary effluent was treated with different doses of UV irradiation. To achieve a 3 log₁₀ reduction of E. coli, FCV, poliovirus, and MS2 doses of 3.99, 14.28, 20.63 and 46.95 mWsec/^cm2 respectively were required. In this study FRNA bacteriophage was clearly the most resistant organism to both UV and chlorination whereas FV was susceptible to inactivation by chlorination but more resistant to inactivation by UV^_.

Reference:

J.A. Tree, M.R. Adams and D.N. Lees, 2005. Disinfection of of Feline Calicivirus, (a surrogate for novovirus) in waste waters. Journal of Applied and Environmental Microbiology, 98: 155-162 .