(A) PFGE profiles of ApaI-digested chromosomal DNA of five L. monocytogenes isolates recovered from case-patients. Lines 1 and 9, molecular size markers; lines 2, genotype B isolate from case-patient; lanes 3, 4 and 5, genotype A isolates from case-patients; line 6, genotype A1 isolate from case-patient; lines 7, genotype C isolate (L. monocytogenes) from animal; line 8, genotype D isolate (L. innocua) from animal. (B) Dendrogram resulting from computer-assisted analysis of the profiles shown in panel A. P. fluid: peritoneal fluid.