In a word, no. Vitiligo is definitely not fatal.
The condition is not life-threatening. At most, people with the condition may experience a mild itch over the affected skin. However, for the most part, vitiligo rarely presents with any itch or pain.
The largest source of harm from vitiligo comes from general ignorance and lack of knowledge with respect to the condition. The resultant social stigmas attached to vitiligo cause far-reaching effects on people's confidence and general well-being.
While vitiligo itself is not harmful, it does have associations with certain immune-mediated conditions which should be excluded. These include autoimmune thyroid disease, type 1 diabetes, and autoimmune arthritis, to name a few.
I hope this helps to address the question.
Dr Chris Lim