Table 4.
Characteristics Associated with Strain Sharing Among 350 Escherichia coli Isolates from Multisubject Households
| Strain Characteristics | Trait Prevalence, No. of Strains (Column %) | P value, Shared vs Nonshared | |||
|---|---|---|---|---|---|
| Total (n = 350) | Shared (n = 59) | Nonshared (n = 291) | |||
| Category | Trait | ||||
| Resistance | Fluoroquinolone | 51 (15) | 16 (27) | 35 (12) | .004 |
| Virulence genesa,b,c | iha | 84 (24) | 20 (34) | 64 (22) | .04 |
| gafD | 2 (1) | 2 (3) | 0 (0) | .03 | |
| yfcV | 170 (49) | 37 (63) | 133 (46) | .01 | |
| sat | 78 (22) | 20 (34) | 58 (20) | .02 | |
| pic | 27 (8) | 9 (15) | 18 (6) | .02 | |
| fyuA | 218 (62) | 48 (81) | 170 (58) | .001 | |
| iutA | 107 (31) | 27 (46) | 80 (28) | .005 | |
| kpsM II | 191 (55) | 41 (70) | 150 (52) | .008 | |
| K5 | 31 (9) | 12 (20) | 19 (7) | .002 | |
| usp | 165 (47) | 35 (59) | 130 (45) | .03 | |
| H7 fliC | 34 (10) | 10 (17) | 24 (8) | .04 | |
| malX | 163 (47) | 34 (58) | 129 (44) | .04 | |
| ExPEC | 178 (51) | 45 (76) | 133 (38) | .001 | |
| Clonal group(s)d | ST131 | 45 (13) | 10 (17) | 35 (12) | .20 |
| ST131-H30R | 25 (7) | 8 (14) | 17 (6) | .049 | |
| ST131-H30Rx | 7 (2) | 4 (7) | 3 (1) | .02 | |
| STc73 | 25 | 9 (15) | 16 (5) | .02 |
Abbreviations: ExPEC, extraintestinal pathogenic Escherichia coli; FQREC, fluoroquinolone-resistant E. coli; FQSEC, fluoroquinolone-susceptible E. coli; ST, sequence type; ST131, sequence type 131; STc, ST complex (group of closely related STs); VG, virulence gene.
aVGs shown are those that yielded P < .05 (by Fisher’s Exact Test) for the 2-group comparison. Boldface, higher prevalence group (all prevalence differences favored the shared strains). Traits definitions: iha, adhesin-siderophore receptor; gafD, G fimbriae; yfcV, putative chaperone-usher fimbria; sat, secreted autotransporter toxin; pic, protein associated with intestinal colonization; fyuA, yersiniabactin receptor; iutA, aerobactin receptor; kpsM II, group 2 capsules; K5, group 2 capsule variants; usp, uropathogenic-specific protein; H7 fliC, flagellar variant; malX, pathogenicity island marker.
bVGs detected in ≥1 isolate but not yielding P < .05: papAH/C/EF/G (P fimbriae: 21%–24%, respectively), sfa/focDE (S and F1C fimbriae, 18%), sfaS (S fimbriae adhesin, 5%), focG (F1C fimbriae adhesin, 9%), afa/draBC (Dr-binding adhesins, 3%), fimH (type-1 fimbriae adhesin, 98%), hra (heat-resistant agglutinin, 23%), hlyD (alpha hemolysin, 17%), hlyF (variant hemolysin, 8%), cnf1 (cytotoxic necrotizing factor 1, 13%), cdtB (cytolethal distending toxin, 7%), vat (vacuolating toxin, 31%), astA (enteroaggregative E. coli toxin, 7%), tsh (temperature-sensitive hemagglutinin, 6%), iroN (salmochelin receptor, 25%), ireA (catecholate siderophore receptor, 11%), chuA (heme-binding outer membrane, 73%), kpsMT III (group 3 capsules, 3%), K1, K2, K2/K100 (group 2 capsule variants, 20%, 51%, 4%, respectively), iss (increased serum survival, 7%), rfc (O4 lipopolysaccharide, 6%), cvaC (microcin V), traT (serum resistance-associated, 44%), ibeA (invasion of brain endothelium A, 16%), ompT (outer membrane protease, 66%), clbB/N (colibactin (polyketide) synthesis, 20%).
cTraits sought but not detected in any isolate: afaE8, F17, clpG, bmaE (variant mannose-resistant adhesins).
dClonal groups detected in ≥1 isolate but not yielding P < .05 (% of 350): STc12 (5%), ST127 (2%), ST141 (4%), ST144 (1%), ST372 (1%), STc405 (2%), STc648 (1%), STc95 (5%), STc69/CGA (5%). Each of the 12 clonal groups sought was detected in at least one isolate.