In the 1950s, Spanish professional barbers disinfected brushes by immersing them in bleach water, reduced to 10%. There are models that are still sold, from DANIDOM, that the knot separated from the handle (boxwood) and that were designed specifically for professionals. If the smell of hypochlorite is not pleasant, it can then be immersed in water to rinse it off. Danidom brushes are extremely cheap and professional (only whole bristles), less than 10 euros More information about Danidom, in : https://refineriadecaballeros.wordpress.com/category/afeitado-marcas-brands/danidom/
Not sure if the chemicals would damage the fibers or not. They don’t absorb water and soaps and creams keep them clean so there’s not much else to do. Unless you dropped it in the toilet... In that case I’d use some anti bacterial hand soap or maybe dish soap.
This is the advice I'm seeing on YouTube also. Think I'll be safe and just use a little Dawn dish soap. Thank you.