Advance in PCR Assays for Detection of Streptococcus suis

Streptococcus suis is an important pathogen of pigs and occasionally causes serious human disease.It has thirty-five different capsular serotypes(types 1/2 and 1 through 34).Serotypes 1,2,7,9,and 14 are usually isolated from diseased or dead pigs and serotype 2 is considered to be the most-virulent serotype.Specific primers were designed and synthesized based on 16S rRNA and sly,gdh,cps,mrp,epf gene sequences of known Streptococcus suis strains.The PCR or multiplex PCR assays were developed for the detection of group and serotypes 1(plus 14),2(plus 1/2),7,9 and the discrimination of serotype 2 virulent strains and serotype 1 highly virulent strains of Streptococcus suis in clinical samples or bacterial isolates with higher sensitivity and specificity,no cross reaction with other pathogenic bacteria and other serotypes of Streptococcus suis.The PCR assays can be rapid,simple,useful tools both for diagnostic purposes and in epidemiological and transmission studies of porcine streptococosis.