To use this AFB test, you simply need to take a larva, shake it up into the bottle, and drop the resulting liquid in the test cassette. The image shows a negative test (one line, not two).
American foulbrood is a serious brood disease. It is spread by spores that can be present in honey and other hive products, and on hive tools and components. AFB is commonly spread by robbing of weakened hives. The NSW DPI recommends that beekeepers check their hives for AFB in October and test them if possible. Dept of Ag Vic its Spring and Autumn. Records must be kept. Please see Bee Aware for more information on AFB.