An Attempt to Reactivate Mercuric Bichloride Inactivated Vaccinia Virus

Abstract

A property common to many enzymes 1 , 2 is the ease with which mercury bichloride inactivation may be quantitatively reversed. Such reactivation after bichloride inactivation has also been demonstrated with bacteriophage 3 , 4 and since some workers have postulated an analogy between phage and viruses the following experiments were undertaken to determine whether or not bichloride inactivated vaccinia virus could be reactivated.

The least amount of mercury bichloride which would extinguish the reaction of the viruses in rabbit skin was first determined. A calf-skin strain (dermovaccine) and a rabbit-brain strain (neurolapine) of virus were used. Heated and unheated virus-saline mixtures were used as controls. Portions of a 1–500 suspension of the viruses (known to be active in a 1–1,000 suspension) were exposed to equal amounts of various mercury bichloride dilutions for 24 hours at room temperature. One-tenth cubic centimeter of each virus-bichloride or virus-saline mixture was injected intradermally into corresponding shaved skin areas on 2 albino rabbits. The heated virus-saline or heated virus-bichloride mixtures caused no reaction on the skin of rabbits. The reaction of the dermovaccine was extinguished by the 1–10,000 dilution but not by the 1–100,000 dilution of bichloride. The reaction of the neurolapine was extinguished by a 1–1,000 but not by any higher dilution of bichloride.