Effect of chemical& physical agents on viruses Heat is the most reliable method of virus disinfection Most human pathogenic viruses inactivated by exposure to60°cfor30mns Viruses are stable at low temperatures and are routinely stored at-40to-80° Some viruses are rapidly inactivated by drying, others survive well in a desiccated state UV light inactivates viruses Enveloped viruses(lipid in envelope) are inactivated by organic solvents Phenols, alcohols Qacs active against viruses Most active agents are chlorine, hypochlorites, iodine, aldehydes. ethylene oxide