1. A virus composition comprising:one or more live, attenuated flaviviruses; and a stabilizing composition comprising serum albumin and trehalose,
wherein the one or more live, attenuated flaviviruses consists of one or more Dengue viruses;
wherein the serum albumin is serum albumin from a vertebrate species, and is present at a concentration of 0.001 to 3.0% (w/v);
wherein the trehalose is present at a concentration of at least 15% (w/v); and
wherein the composition is capable of reducing the inactivation of the one or more live, attenuated Dengue viruses.