Background Shigella is one of the top five causative agents of childhood diarrhoea, particularly in lower-middle-income countries, and is one of the vaccine-preventable diseases prioritised for vaccine development by the WHO. The emergence of antibiotic-resistant strains of Shigella is a major public health concern as it reduces the effectiveness of available diarrhoeal treatment and management options. We performed drug susceptibility testing using the BD Phoenix 100 automated microbiology system on shigella isolates from Zambian children under five years presenting with diarrhoea at selected health facilities.

Methods We tested 86 shigella isolates from children U5 from outpatient and hospitalised children during a Shigella surveillance study in Lusaka and Ndola collected between 2020–2021.

Results A high proportion of the Shigella isolates showed resistance to trimethoprim/sulfamethoxazole (79.1.4%), Ampicillin (56.9%), amoxicillin-clavulanate (49.4), Cefuroxime (55.8.1%), and gentamicin (49.4%). Resistance to Ciprofloxacin was observed in only two isolates. Overall, 83.7% (n=72) of the isolates exhibited resistance to at least one class of antibiotics. This included 59.3% (n=51) resistance to Cephalosporins, 79.1% (n=68) to Sulfonamides, 57% (n=49) to Penicillin, 48.8% (n=42) to Aminoglycosides and 25.6% (n=22) to beta-lactams. Multi-drug resistance (resistance to 3 or more drug classes) was observed in 62.8% (n=54) of the isolates. More MDR was observed in in-patient isolates, 71.4%( n=10/14), compared to 61.1% (n=44/72) in outpatient isolates. At the species level, multi-drug resistance was observed in 25/29 isolates identified as S. sonnei and 24/33 S. flexneri isolates.

Conclusion Our research indicates a high proportion of antibiotic resistance among the Shigella isolates from young children, which has significant implications for managing Shigella infections. The results support the urgent need for action on effective strategies for Stewardship (i.e. revision of guidelines) and interventions such as vaccines to mitigate the evolution and spread of AMR.