[Morphological alteration and desintegration of dane particles after exposure with "Gigasept". A first methological attempt for the evaluation of the virucidal efficacy of a chemical disinfectant against hepatitisvirus B ( author's transl)].

A test system based on morphological alterations and desintegration of hepatitis virus B (HBV) is presented for the approximative evaluation of the virucidal efficacy of a chemical disinfectant. Dane particles, supposed to be the infectious entity of HBV, were partially purified by a trap and a rate zonal ultracentrifugation from serum samples of a patient with chronic hepatitis undergoing an immune suppressive treatment because of leukemia. "Gigasept" on the basis of succine dialdehyd and formaldehyd served as disinfectant for this investigation. In one experiment partially purified Dane particles were exposed to the action of a 5% solution of "Gigasept" on electron microscopic grids. Morphological alterations resulting in derounding, break up of the outer membrane, spiral uncoiling as well as asymmetric enlargement of the space between the outer membrane and the core of the HBV was observed after 2 mins. After 15 mins, the HBV were diffusely stained with loss of the characteristic substructure and became polygonal. The decrease of the number of the particles was proportional to the length of the contact time with the disinfectant. In a second series equal volumes of a 5% solution of "Gigasept" and of a HBV containing serum were in contact for 2 hours, with consecutive purification and morphological characterization of the HBV. The sedimentation of the HBs antigenicity differed from the control. A part of the Dane particles was diffusely stained and lost its substructure. Moreover empty particles in the range of the HBc antigen were found. Another part of Dane particles, however, was morphologically unchanged. The relation of intact and non intact particles could possibly serve as parameter for the HBV virucidy.-Thermo inactivation (3 mins, +98 degrees C) of the HBV in a serum was undertaken for comparison.