Serotypes and Hemagglutinin Gene Sequences of Avibacterium paragallinarum Isolated in Taiwan.

Abstract

Despite routine vaccine use, sporadic outbreaks of infectious coryza in poultry continue to occur in Taiwan. This study was designed to determine the serotypes and the complete nucleotide sequences of a hemagglutinin gene () ofisolated in Taiwan between 1994 and 2017. Hemagglutination inhibition tests showed that these isolates belong to serogroups B and C. Sequence analyses of thegene showed that Taiwanese serogroup B isolates are most similar (94.7%-98.2% identity) to strain FARPER-174 isolated in Peru in 2015. In contrast, Taiwanese serogroup C isolates are most similar (96.3%-99.8% identity) to strain H-18 isolated in Japan in 1976. This is the first report showing the presence ofof serogroup B in Taiwan. In addition, one Taiwanese isolate showed cross-reactivity with serogroup B and C antisera. This isolate contains a chimericgene that might result from recombination between serogroups B and C. These findings could be valuable for the epidemiologic study and molecular serotyping of.