An antimicrobial and antiviral barrier composition for topical application to the proximal anterior nares includes an antiseptic solution in combination with one or more citrus oils such as, for example, citrus sinensis (orange oil). Various embodiments may also include one or more of the following additional ingredients: lauric acid; d-limonene; soy oil; emu oil; grapefruit seed extract; glycine soja; simmondsia chimensis (Jojoba); aloe vera; and a preservative, such as sodium benzoate, BHT, benzalkonium chloride, vitamin E.