Two pairs of primers were dsigned from cholera toxin subunit A(ctx A)gene and a nested PCR that can detect O1 classical (CVC),El Tor (EVC)and O 139 especially was established.

• 针对霍乱弧菌肠毒素A亚单位（ctx?A）基因设计两对引物，建立套式PCR，可特异扩增霍乱弧菌O1群古典型、埃尔托型和O139群；