Pressure reversal of halothane's antiviral effect.

The authors have studied the effects that hyperbaric pressure and halothane had on measles virus replication. Two per cent halothane at one atmosphere of air (ATA) reduced the number of infectious measles virus particles produced in cultured Vero cells by greater than four orders of magnitude (P less than 0.001) relative to virus produced in untreated cultures at 1 ATA. The same concentration of halothane at 100 ATA still reduced the amount of virus synthesized but only by 1 1/2 orders of magnitude (P less than 0.01) as compared with control cultures. Pressure (100 ATA) alone reduced virus production insignificantly. Thus, it appears that the antiviral effects of halothane on measles virus replication in cultured Vero cells is reversible at least partially by pressure.