Inactivation of yellow fever virus by glutaraldehyde.

The preservation of cellular ultrastructure by glutaraldehyde is well documented (D. D. Sabatini et al., J. Cell Biol. 17:19, 1963); however, we could find no report of its inactivation of the yellow fever virus in tissue. As laboratory infection of unvaccinated personnel by this virus is also well known (G. P. Berry and S. F. Kitchen, Am. J. Trop. Med. 11:365, 1931), it is important to ascertain whether yellow fever virus in tissue is inactivated by glutaraldehyde. Mouse brain and monkey liver infected with yellow fever virus (Asibi strain) titering greater than 105 mouse intracerebral lethal dose50 were diced into 1to 2-mm blocks. Half of these blocks were placed in a 5% glutaraldehyde solution in 0.1 M phosphate buffer prepared by the method of Sabatini (J. Cell Biol. 17:19, 1963) and half were placed in 1% rabbit serum in sterile 0.1 M phosphate-buffered saline (pH 7.2). After contact with these solutions for 2 hr at 20 C, the blocks were washed three times in the rabbit serum buffer; a 20% emulsion was prepared and log dilutions were made with this same buffer. Six Fort Detrick white mice (8 to 10 g) were inoculated intracerebrally with 0.03 ml of each dilution of the emulsion made from the glutaraldehydeexposed tissue. A similar titration of the untreated tissue emulsion was performed. Over a 21-day observation period, none of the mice given glutaraldehyde-treated tissue emulsion died, whereas all mice receiving through and including 10-4 dilution of the untreated material died. We conclude from these studies that yellow fever virus in 1to 2-mm blocks of tissue is inactivated by 5% glutaraldehyde within 2 hr.