Serotyping of Haemophilus paragallinarum isolates from Mexico by the Kume hemagglutinin scheme.

This study was conducted to determine the occurrence of Kume serovars of H. paragallinarum in Mexico. A total of 42 isolates of H. paragallinarum from 6 Mexican states were serotyped by the Kume haemagglutinin scheme. Serovars A-1, A-2, B-1, and C-2 were recognized among 11 (26.2%), 7 (16.6%), 4 (9.5%), and 14 (33.3%) isolates, respectively. Six isolates (14.3%) further showed haemagglutinating activity but could not be classified into any serovar. Commercial vaccines containing Kume serovars A-1, A-2, B-1, and C-2 may provide better protection than those bi- or trivalent infectious coryza vaccines currently used in Mexico.