A new category of methicillin-resistant Staphlylococcus aureus (MRSA), called community-acquired MRSA (CA-MRSA), has emerged worldwide. In contrast to previous MRSA, most CA-MRSA carries the Panton-Valentine leukocidin (PVL) genes (luk(PV)SF) as a virulence genetic trait. Sequence analysis of the luk(PV)SF gene of a Japanese isolate demonstrated that the gene has more similarity to methicillin-susceptible S. aureus from France than MRSA from the United States. Based on the sequences, we developed a real-time PCR assay for the three key genes of CA-MRSA; that is, luk(PV)SF, mccA (for methicillin resistance), and spa (for S. aureus). Dual or triple assay for luk(PV)SF, mecA, and spa in one test tube became possible. The detection limit of the assay with probe and SYBR Green methods was between 2.7 and 2.7 x 10(1) CFU/ml. The assay detected PVL-positive MRSA in clinical (blood) isolates. (C) 2005 Elsevier Inc. All rights reserved.