Long-Term Zinc Application May Ease Cold Sore Occurrence

Long-Term Zinc Application May Ease Cold Sore Occurrence

ST. LOUIS--In the May issue of Journal of Clinical Microbiology(38(5):1758-1762, 2000), researchers found that zinc may inhibit cold sores byinactivating isolates of the herpes simplex virus (HSV). Some companies havealready incorporated zinc into consumer ointments.

Researchers, led by Max Arens from the Washington University School ofMedicine, tested zinc salts in a standard plaque assay with clinical isolates ofHSV. The virus, which was kept incubated, was treated with zinc and then dilutedand placed onto cells for detection and quantification of the remaininginfectious virus. Of 10 randomly chosen isolates, seven were inactivated by zincgluconate and nine were inactivated by zinc lactate. The effectiveness wasdose-dependent, with 50 mM of zinc causing 100-percent virus inactivation and 15mM being approximately 99 percent effective. However, these results came aftertwo hours of application; five-minute treatments with zinc gluconate, lactate,acetate or sulfate yielded inactivation rates of zero to 55 percent. For a copyof the abstract, visit http://jcm.asm.org.