Thanks for writing in.
The most common cause in your case scabies
It is caused by a type of ectoparasite called sarcoptes scabies.
It is common and treatable.
You can take oral medications like ivermectin
Also you can apply permethrin lotion overnight.
Keep the area clean and dry.
It better to visit a dermatologist
before taking these medication.
is considered contagious.It can spread to other family members.
Also treatment of family members is also essential.
I encourage you to visit a qualified dermatologist for proper advise and treatment.
Hope this helps.