This is usually harmless and not contagious. Milia are typically 1-4 mm white cysts, may arise spontaneously, and can also follow irritation, trauma, thick occlusive products, long-term topical steroid use, or certain skin procedures.
Andrews' Diseases of the Skin E-Book Clinical Dermatology, p. 782.
DermNet's milia overview describes them similarly.
I cannot make a definite diagnosis from one close-up photograph, and the lighting makes it hard to judge true pigment changes. But this does not look typical for vitiligo.
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Closed comedonal acne
Usually many skin-colored or white bumps, often on cheeks, forehead, chin, or jawline. Can be worsened by comedogenic cosmetics, hair oils, sweating, and hormonal acne.
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Pityriasis alba
This causes larger, flat, poorly defined lighter areas with fine dryness or scale, often on the cheeks. It is more noticeable after sun exposure. The image does not strongly suggest it because the visible lesions seem raised. Dermatology 2-Volume Set, p. 1324.
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Post-inflammatory hypopigmentation
Lighter marks after acne, eczema, irritation, scratching, or a healing rash. These are usually flat, rather than firm tiny bumps.
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Tinea versicolor
A superficial yeast rash with fine scale, usually more prominent on the trunk, neck, shoulders, or upper back. Facial involvement can occur, but the photo is not classic for this. A clinician can check scale or perform a simple KOH scraping if needed.
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Vitiligo
Typically flat, clearly defined, completely white patches rather than multiple tiny raised papules. A dermatologist can assess this with a Wood lamp if there is doubt. Andrews' Diseases of the Skin E-Book Clinical Dermatology, p. 1002.