Iowa Admin. Code r. 21-22.6
If upon inspection American Foulbrood disease is detected in colonies, those colonies shall be identified and the disease abated in a timely manner that will prevent spread to neighboring colonies or apiaries as determined by the state apiarist.
The method of disease cleanup will be specified following inspection, depending on the severity of the infection and strength of the bee colony. A strong colony with a light infection of American Foulbrood may be treated with Terramycin or diseased Cornbs removed or a Cornbination of these methods. A severely infected, weak colony must be killed and the diseased Cornbs destroyed by burning or melting at a temperature high enough to kill disease spores. In any case, all Cornbs containing American Foulbrood scale shall be destroyed.
Iowa Admin. Code r. 21-22.6