They are viral. Molluscum contagiosum are viral infections of the skin, which ocdcur mainly in children. They are contagious and spread from child to child, by playing, touching, and sharing towels and clothing. They are treated by many doctors with creams, like retinoic acid or imiquimod, and can also be treated, if done carefully by certain wart medicines. They frequently go away in time by themselves.
No. Molluscum contageosum is a viral infection much like warts. If you do nothing, it will run its course eventually (sometimes years). Whether or not you take vitamins may effect your over all health, but not the course of molluscum. There are both conventional and alternative treatments available (i prefer the alternative). See your doctor if the molluscum bothers you, or don't if it doesn't.