1. A method of producing a viral antigen from an enveloped virus, comprising the following steps in that order: a) providing a fluid containing an enveloped virus, b) clarifying a fluid containing said enveloped virus, resulting in a liquid product containing said enveloped virus, c) reducing the volume of liquid product obtained after stage b) to obtain a concentrated liquid product, d) solubilizing the enveloped virus present in the liquid product by adding detergent or a mixture of of the agents containing the cationic detergent to the concentrated liquid product obtained in step c), e) separating the viral nuclei from the composition obtained after step d), and f) optionally, removing the cationic detergent from the composition obtained after step e), and g) purification viral antigen, with step c) immediately followed by step d) .2. The method according to claim 1, characterized in that the purification step directed to the specific purification of the enveloped virus is not carried out to step d). The method according to claim 1 or 2, characterized in that the only chromatography step that is carried out is carried out in step g). The method according to claim 1 or 2, characterized in that the density gradient ultracentrifugation and / or chromatography is not carried out until step d). The method according to claim 1 or 2, characterized in that the stage of inactivation and / or the stage of removal of the virus. The method according to claim 1 or 2, characterized in that the volume reduction ratio in step c) is at least 4, preferably at least 5.7. The method according to claim 1 or 2, characterized in that the final concentration of the cationic detergent is at least1. Способ получения вирусного антигена из оболочечного вируса, включающий следующие стадии в указанном порядке:a) обеспечение жидкости, содержащей оболочечный вирус,b) осветление жидкости, содержащей указанный оболочечный вирус, приводящее к получению жидкого продукта, содержащего указанный оболо
