Epidemiological study of Mycoplasma pneumoniae infections in japan based on PCR-restriction fragment length polymorphism of the P1 cytadhesin gene.

Two hundred fifty strains of Mycoplasma pneumoniae isolated during the past 20 years in Japan were classified into two groups (I and II) based upon different PCR-restriction fragment length polymorphism patterns of their P1 cytadhesin genes. Clear shifts between the M. pneumoniae groups were observed but did not appear to be correlated with M. pneumoniae epidemic cycles. Patients' sera showed relatively higher levels of antiadhesin antibodies to M. pneumoniae strains homologous with the infecting strain.