Inactivation of Coxsackievirus B4, Feline Calicivirus and Herpes Simplex Virus Type 1: Unexpected Virucidal Effect of a Disinfectant on a Non-Enveloped Virus Applied onto a Surface

Abstract

Objective: To evaluate the effect of a disinfectant onto viruses in suspension on the one hand and applied onto a surface on the other. Methods: A system combining flocked swabs to recover viruses dried onto stainless steel carriers and gel filtration to eliminate cytotoxic products has been developed to study the virucidal effect of a quaternary ammonium-based disinfectant towards herpes simplex virus type 1 (HSV-1), coxsackievirus B4 (CVB4) and feline calicivirus F9 (FCV). The recovery of FCV has been estimated by RT real-time PCR. Results: HSV-1, CVB4 and FCV had a titer over 10⁴ TCID₅₀ · ml^-1 after 2 h drying and were recovered from the carriers using flocked swabs. HSV-1 was inactivated in suspension and on stainless steel carriers by the disinfectant (a reduction factor of 4 and 2.83 log, respectively) whereas CVB4 was resistant. The reduction of infectious titer was moderate, 1.5 log in 30 min, when FCV was in suspension, whereas it was up to 4 log in 10 min when the virus was dried on a carrier. Dried FCV was efficiently recovered from carriers as demonstrated by RT real-time PCR. Conclusion: A non-enveloped virus, FCV, applied on a surface, but not in suspension, was inactivated by a quaternary ammonium-based disinfectant. The resistance of viruses applied onto a surface to the effect of disinfectants should be investigated further.

Survival of Enveloped and Non-Enveloped Viruses on Inanimate Surfaces

“…CVB4E2-positive strand RNA was quantitated by two-step quantitative RT-PCR as described previously ( 15 ). Briefly, total RNA was extracted with the RNeasy minikit (Qiagen, Valencia, California).…”

“…Non-enveloped viruses, such as coxsackieviruses, rotavirus, or poliovirus, can survive for extended periods on surfaces ( 9 , 10 ), while enveloped viruses, including H1N1 and human coronaviruses, remain infectious on surfaces after several days ( 6 ). The persistence of dried viruses is affected by various environmental conditions and factors such as heat, moisture, pH, and the type of surface ( 12 , 15 ). Furthermore, the compositions of media may also influence the persistence of viruses.…”

Viruses Contained in Droplets Applied on Warmed Surface Are Rapidly Inactivated

“…CVB4E2 positive strand RNA was quantitated by two-step quantitative RT-PCR as described previously ( 25 ). Briefly, total RNA was extracted with RNeasy minikit (Qiagen, Valencia, Calif.) and resuspended.…”

Resistance of Enteric Viruses on Fomites

“…Data from these studies revealed a complete or relative lack of efficacy of quaternary ammonium against all of the viruses tested [76,78,79]. In another study FCV applied on a surface, but not in suspension, was effectively inactivated by a quaternary ammonium-based disinfectant, while CVB4, an enterovirus, was resistant [80]. Ethanol has shown minimal efficacy against human norovirus and FCV, but it is active against MNV, with a clear dose-dependent impact [76,[81][82][83].…”