Research has lately been finding that essential oils can kill harmful bacteria and fungus. In fact, a quote from Mercola.com cited this study:

"Dr. Diane Horne of Weber State University in Ogden, Utah, told the 98th general assembly of the American Society of Microbiology about the serendipitous discovery of the impact of the oils on cells such as Streptococcus pneumonia.
A coresearcher was spraying aromatic oils in the laboratory. "When I looked at the S. pneumonia that I was preparing for another experiment, the cells were just falling apart," Dr. Horne reported. Dr. Horne and coworker Sue Chao, of the Young Living Essential Oil Company of Payton, Utah, tested the autolyzing properties of 74 different essential oils.
The best results occurred with oregano, thyme and rosewood and intermediate inhibition of the pathogens was achieved with cinnamon oil and clove oil, Dr. Horne said at a poster presentation at the meeting. Dr. Horne pointed out that the oils also showed efficacy against E. coli and several species of fungi."


After reading this you may be wondering how you can get essential oils.  Many health food stores sell them, or you can them online. I ,personally, have found oregano oil good for killing fungus; it also helps with respiratory issues. Clove is good for tummy aches and diarrhea. Hooray for herbs!