Detection Of Drug Resistance And Identification Of Resistance Gene In 122 Strains Of Steptococcus Suis Type 2

Streptococcus suis was a well-recognized worldwide swine pathogen.It was a zoonoses,especially S.suis serotype 2 which could cause septicemia and meningitis in humans,even to die.S.suis 2 could lead to meningitis,arthritis,endocarditis,and septicemia of pigs.Moreover,healthy pigs could carry S.suis in their nasal cavities, tonsils andupper respiratory tracts,contributing to the dissemination and transmission of this pathogen.The study were aimed to investigate the prevailing of drug resistance and drug resistance genes in Streptococcus suis type 2 isolated from different areas of China.122 strains of Streptococcus suis type 2 collected from Hunan,Hubei,Henan, Zhejiang,Guangdong,Jiangxi and Anhui between 2004 and 2006 were tested using K-B (Kir by Bauer) method.The results showed that 122 isolated strains were sensitive to vancomycin,ciprofloxacin,amoxicillin and cephalothin,and also showed that the strains were resistant to erythromycin,aminoglycosides and tetracycline.According to statistic datas,multiple drug resistance was found to be common among strains from different area of China.Most strains were resistant to 5 or 6 antibiotics.These strains usually could resist to sulfonamides,erythromycin,tetracycline and streptomycin.Resistance genes of macrolides(ermA,ermB,and mefA),tetracycline(tetM,tetC and tetO) and aminoglycosides(aph3′) in 122 strains were studied by PCR.The highest coincidence of drug resistance and genotype is macrolides(78.8%).The accord rates of the other two antibiotics are 24.6%and 31.1%respecitively.The resistance genes(ermB,tetM and Aph-3) which were commonly found were sequenced and analyzed in the web of GenBank.The sequence of ermB was blasted with that gene of Staphyloccocus aureus rosenbach,Streptococcus pneumoniae and other streptococcus suis strains.The result showed that the homology wad up to 99%,It is helpful for us to know the kinship and the transfer mechanism.In conclusion,drug resistance to 13 antibiotics of 122 Streptococcus suis type 2 strains collected from 13 province between 2004 and 2006 was analyzed in this study. The result revealed that the drug resistance of the strains in China was sevious and widespread.It is helpful to the prevention and treatment of this disease.