Analysis of virulence genes in methicillin-resistant Staphylococcus aureus isolates from a pediatric population

Objective To determine the molecular epidemiology and presence of virulence genes in Staphylococcus aureus (S.aureus) isolates from primary school students in Guangzhou.Methods Nasal swab samples were collected from healthy primary school students in Guangzhou.The polymerase chain reaction (PCR) technique was applied to test the virulence genes from S.aureus strains.Results Overall,40.1% and 1.2% of the isolates were classified as S.aureus and methicillin-resistant S.aureus (MRSA) among 1 012 primary school students,respectively.The leading toxin genes were hlb,sak,scn,chp and sep genes in S.aureus,followed by seA,seB and seC genes.The frequency of chp,seB,seC and pvl genes was higher in MRSA than in methicillin-susceptible S.aureus (MSSA) (P<0.05).The coexistence of two or three virulence genes was higher in MRSA than in MSSA(P <0.05).Conclusion The relative high frequency of S.aureus and its virulence genes among healthy primary school students in Guangzhou warrants further attention considering the potential pathogenic ability of MRSA.