Comprehensive Comparison of Cultivable Norovirus Surrogates in Response to Different Inactivation and Disinfection Treatments

Abstract

g Human norovirus is the leading cause of epidemic and sporadic acute gastroenteritis. Since no cell culture method for human norovirus exists, cultivable surrogate viruses (CSV), including feline calicivirus (FCV), murine norovirus (MNV), porcine enteric calicivirus (PEC), and Tulane virus (TuV), have been used to study responses to inactivation and disinfection methods. We compared the levels of reduction in infectivities of CSV and Aichi virus (AiV) after exposure to extreme pHs, 56°C heating, alcohols, chlorine on surfaces, and high hydrostatic pressure (HHP), using the same matrix and identical test parameters for all viruses, as well as the reduction of human norovirus RNA levels under these conditions. At pH 2, FCV was inactivated by 6 log 10 units, whereas MNV, TuV, and AiV were resistant. All CSV were completely inactivated at 56°C within 20 min. MNV was inactivated 5 log 10 units by alcohols, in contrast to 2 and 3 log 10 units for FCV and PEC, respectively. TuV and AiV were relatively insensitive to alcohols. FCV was reduced 5 log 10 units by 1,000 ppm chlorine, in contrast to 1 log 10 unit for the other CSV. All CSV except FCV, when dried on stainless steel surfaces, were insensitive to 200 ppm chlorine. HHP completely inactivated FCV, MNV, and PEC at >300 MPa, and TuV at 600 MPa, while AiV was completely resistant to HHP up to 800 MPa. By reverse transcription-quantitative PCR (RT-qPCR), genogroup I (GI) noroviruses were more sensitive than GII noroviruses to alcohols, chlorine, and HHP. Although inactivation profiles were variable for each treatment, TuV and MNV were the most resistant CSV overall and therefore are the best candidates for studying the public health outcomes of norovirus infections.

Comparative Virucidal Efficacy of Seven Disinfectants Against Murine Norovirus and Feline Calicivirus, Surrogates of Human Norovirus

“…The short contact time used in previous studies (< 5 min) could explain the absence of any significant effect of alcohol (D'Souza and Su 2010) and of chlorhexidine (Park et al 2010;Iwasawa et al 2012;Matsuhira et al 2012) on the infectious titre of MNV and FCV. Our results as well as previous studies confirmed that MNV is more susceptible to alcohol and chlorhexidine than FCV (Park et al 2010;Tung et al 2013;Cromeans et al 2014). These data also suggest differences between MNV and FCV regarding viral capsid integrity (Cannon et al 2006;Park et al 2010).…”

Quantification of Human Norovirus GII on Hands of Mothers with Children Under the Age of Five Years in Bagamoyo, Tanzania

“…First, the detection of viral RNA does not necessarily indicate the presence of infectious NVGII. However, given that human noroviruses are not currently cultivable, 35 research to determine infectious prevalence would need to be undertaken with a surrogate calicivirus 36 and, as such, may also not accurately reflect the prevalence of infectious norovirus on mothers' hands. Second, this study only represents a cross-sectional comparison of NVGII hand contamination during the rainy versus the dry season.…”

Rhesus enteric calicivirus surrogate model for human norovirus gastroenteritis

“…While the use of human subjects is clearly optimal for at least certain areas of human NoV research, it has its own limitations including the time-consuming and highly regulated processes associated with human subject research, the unknown preexposure history of the volunteers, the restricted sampling procedures, the associated cost and facilities, and the lack of cell culture system for the analysis of clinical samples. (Cromeans et al, 2014;Wang et al, 2013). However, the major value of the ReCV/macaque model over the other surrogate models is its human NoV-like diversity and this point should not be ignored.…”