FIG. 6.

PCR-RFLP gel with the following profiles: lane 1, 100-bp ladder; lanes 2 and 3, profile a from outbreak 7; lanes 4 and 5, profile b from outbreak 1; lanes 6 and 7, profile c from outbreak 5; lanes 8 and 9, profile f from outbreak 9; lanes 10 and 11, profile g from outbreak 10; lanes 12 and 13, profile s from outbreak 8; lane 14, 100-bp ladder; lane 15, profile d; lane 16, profile e; lane 17, profile ga; lane 18, profile h; lane 19, profile k; lane 20, 100-bp ladder. The two bands at approximately 185 and 325 bp in profile b, lanes 4 and 5, are unstable and do not appear on all gels when repeated PCR-RFLP analyses are performed on the same DNA.