Multidrug-resistant non-typhoidal Salmonella and Escherichia coli in imported poultry products in the Maldives

TL;DR

This study found high rates of multidrug-resistant Salmonella and E. coli in imported poultry products in the Maldives, highlighting food safety and public health risks.

Contribution

The first survey of antimicrobial resistance in poultry products in the Maldives, revealing high prevalence of MDR bacteria.

Findings

69% of Salmonella isolates were resistant to tetracycline, and 38% to multiple antibiotics.

38% of Salmonella and 26% of E. coli isolates were multidrug-resistant.

E. coli was more commonly found in chicken meat, while Salmonella was more prevalent in skin.

Abstract

Antimicrobial resistance (AMR) increasingly compromises food safety and public health worldwide. Poultry products are major vectors for AMR bacteria in the food supply. We conducted the first preliminary survey of non-typhoidal Salmonella (NTS) and Escherichia coli on imported poultry in the Maldives. A total of 30 frozen whole chicken samples (15 processed as whole and 15 separated into meat and skin) and 3 pooled egg samples (10 eggs per pool) were obtained from supermarkets and grocery stores in Greater Malé between June 2022 and July 2022. Standard culture methods (Food and Drug Administration Bacteriological Analytical Manual) were used to isolate NTS and E. coli, and isolates were tested for susceptibility to five antibiotics (ampicillin, ceftriaxone, ciprofloxacin, tetracycline and trimethoprim-sulphamethoxazole) by disc diffusion [European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines]. NTS was recovered from 10 of 30 (33.3%) chicken samples, predominantly from skin (9/15) versus meat (3/15); E. coli was found in 15 of 30 (50%) samples, more often in meat. One pooled egg sample (33%) was positive for E. coli. Among 13 NTS isolates, 69% (9/13) were resistant to tetracycline, and 38% (5/13) to ciprofloxacin, ampicillin and ceftriaxone. Thirty-eight per cent (5/13) of NTS were classified by EUCAST as susceptible, increased exposure to ciprofloxacin. Overall, 9 of 13 (69.2%) NTS isolates were multidrug-resistant (MDR; non-susceptible to ≥3 classes). In E. coli, resistance was most common to ampicillin (8/19; 42.1%), followed by tetracycline (5/19; 26.3%), trimethoprim-sulphamethoxazole (4/19; 21.1%), ciprofloxacin (1/19; 5.3%) and ceftriaxone (1/19; 5.3%), with 26.3% (5/19) of E. coli being MDR. These results indicate a substantial prevalence of MDR foodborne bacteria in imported poultry and underscore critical food safety and One Health concerns. Strengthened microbiological surveillance, risk-based import inspection and enhanced regulatory coordination (aligned with the Maldives’ AMR Action Plan) are urgently needed to protect public health.

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