Herd infection rate
Herd infection rate (1)Percentage of herds affected.States or areas must not exceed a cattle or bison herd infection rate, based on the number of herds found to have brucellosis reactors within the State or area during any 12 consecutive months due to field strainBrucella abortus,of 0.25 percent or 2.5 herds per 1,000, except in States with 10,000 or fewer herds. A special review by the Administrator will be made to determine if such small herd population States would qualify for Class A status. Locations of herds, sources of brucellosis, and brucellosis control measures taken by the State will be considered.