Scientific data suggests that rubbing a vinegar solution on the skin is not an effective anti-fungal treatment. The National Institutes of Health warns against using vinegar for medicinal purposes, as skin irritation and hair follicle damage may occur. Scientific evidence doesn't largely support the use of vinegar in modern medicine.
Scientific data does support the fact that vinegar is very high in acetic acid, making it an effective anti-bacterial agent in some instances, according to the American Society for Microbiology. Even when used as a household disinfectant, vinegar is only slightly effective against many strains of infectious agents such as E. Coli and Staphylococcus, according to the National Institutes of Health.