PFGE patterns generated by SmaI digestion of S. pneumoniae serotype 1 isolates recovered from children in Southern Israel during 1994 to 1999. Lanes 1 and 30 contain a lambda ladder; lanes 2 and 29 contain a reference strain, R6, used as a molecular weight marker. Numbers on the left show molecular sizes in kilobases. Lanes 3, 14, 15, and 19 to 21 contain NP isolates; lanes 4 to 13, 16, 17, and 22 to 28 contain blood isolates; lane 18 contains a CSF isolate.