Simple answer, yes, it can. Your saliva contains bacteria, and when that bacteria gets onto your skin it can stimulate congestion in your pores. Once these pores become full there is little you can do without professional treatment to unclog them. If you are over the age of 12, seek the help of a professional esthetician for an extraction treatment.
For very small children, try to exfoliate every day with something very gentle, such as collodial oatmeal. With infants, breast milk can help to clear up baby acne. For older children, use a mild sulfur based acne product, such as Dermalogica's Concealing Spot Treatment. Sulfur is less irritating than benzoyl peroxide or salicylic acid, and children should never use retinoids as they can penetrate into the blood stream with young skin.
An easy way to prevent this is to use an effective silicone barrier when you sleep, such as Clearing Mattifier by Dermalogica. This product will form a barrier between your skin and any nighttime bacterial invaders. Do not use Vaseline as a barrier! The petroleum jelly will significantly clog your pores, and you will wake up with blackheads.
Another easy suggestion is to change pillowcases often. The pillowcase will acquire bacteria more frequently than the sheets on the bed, as there is no barrier (ie pajamas) with preventing bacterial accumulation. Use your pillowcase one night, then flip it over for the next night. On the third day change pillowcases. Getting into this habit will significantly improve a variety of acneic skin conditions. Beware of scented laundry detergents! This can often make the issue worse! Make sure to pick a brand that says "free and clear" on the label, so you will have now risk of reaction to the dyes and fragrances that can often be the culprit with acneic conditions.
If you follow the advice above, your skin should improve, but if after a week you are still encountering significant problems, consult a medical professional for pharmaceutical treatment.
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Should you wish to know more about acne, Acne Vulgaris Article is here