TABLE 1.
Genomic and epidemiological features of S. flexneri versus S. sonnei
| Feature | Descriptiona
|
|
|---|---|---|
| S. flexneri | S. sonnei | |
| Geographical distribution(s) | Low- and middle-income countries | Industrialized countries |
| Multidrug resistance phenotype | AMP + SXT + NAL/CIP | AMP + SXT + NAL/CIP |
| Genotypic resistance determinant(s) | ||
| Resistance gene(s) | ||
| Trimethoprim/sulfamethoxazole | dhfrA1, sulI/sulII | dhfrA1, sulI/sulII |
| Ampicillin | blaOXA-1, blaTEM-1 | bla TEM-1 |
| Ciprofloxacin | QRDR mutations (gyrA and parC) | QRDR mutations (gyrA and parC) |
| PMQR—qnrB/S and aac(6′)-Ib-cr | Efflux—mdfA, acrA/B, and tolC | |
| Efflux—mdfA, acrA/B, and tolC | ||
| Cefotaxime/cefixime | blaCTX-M-15/14, blaCMY2, and blaDHA | blaCTX-M-15/14, blaCMY2, and blaDHA |
| Azithromycin | mphA/ermB | mphA/ermB |
| Mobile genetic elements | ||
| Plasmid type | IncF | Col |
| Integron class(es) | 1 and 2 | 2 |
| PAI(s) | SHI-1, SHI-2, and SRL | SHI-2 |
| Epidemiological feature(s) | ||
| Existing terms | PGs | Lineages |
| Nature of spread | Limited global spread | Greater global spread |
| Dominant clone in India | PG3 | Central Asia III lineage |
a
AMP, ampicillin; SXT, trimethoprim/sulfamethoxazole; NAL, nalidixic acid; CIP, ciprofloxacin; PAI, pathogenicity island; PGs, phylogenetic groups.