I have an interesting friend, with many interesting antics. They have a property with a clear creek running through it, and wanted to know if it had giardia. As

I have an interesting friend, with many interesting antics. They have a property with a clear creek running through it, and wanted to know if it had giardia. Assays are expensive, but metronidazole is cheap, so they drank the water, and determined shortly thereafter, it in fact had giardia.