Thanks for posting your querry
there are a few possibilities.
the first one I can think about is it could be folliculitis
ie., inflammation of hair follicle with a bacteria called staphylococcus aureus
this responds only with rifampicin one per day for four weeks (my own experience)
The other possibility is white piedra
which need confirmation by lab tests.
Both hair and white scale must be tested.
If it is piedra it can be treated with anti fungals
Pl. check with your dermatologist
for proper diagnosis and management
Have a good day