If the problem turns out to be Lymphocystis, there is no known medication to cure it. If it's a mild case, special attention to water quality and diet likely will strengthen the immune system enough to defeat the virus, and the blemishes will fade.
in some articles I read that it dosent infect barbs and other fish from the family, what do you think? im not sure that was true
yes but not all viruses infect all animals..I'm certainly not a marine biologist, Lol, but as far as I know every living creature is suseptical to viruses. When I think of exterior bacterial infections on fish, bumps and lumps don't come to mind. The white patches of Columnaris or deterioration of fins are the markers I associate with bacteria.