The Influence of Some Metal Ions and pH on the Inactivation of Vaccinia Virus by Heat

SUMMARY The addition of metal ions to the suspending medium of vaccinia virus preparations made them more resistant to heat. Monovalent metals were more effective than divalent, but a mixture of the two kinds was the most effective. Heavy metals rapidly destroyed virus infectivity. The protective effect is probably due to the formation of metal-protein complexes with increased resistance to heat denaturation.