Surveillance of Antimicrobial Resistance in Non-Typhoidal Salmonella among Poultry in Ghana

Abstract

Background: Antimicrobial resistance (AMR) is a major global health concern, as it is associated with serious consequences for the treatment of infections. Addressing the fast growing AMR menace requires the use of a One Health approach, encompassing human health, animal health, and the environment. Previous AMR studies in Ghana have given little attention to livestock, a major source of transmission of antibiotic-resistant zoonotic pathogens, such as non-typhoidal Salmonella (NTS). Aim: To determine NTS in the poultry environment in Ghana, including prevalence, risk factors for human acquisition, and AMR. Methods: In total, 612 broiler and egg-laying layer henhouses (306 each in Accra and Kumasi) from 56 poultry farms (34 in Accra and 22 in Kumasi) were sampled in this cross-sectional study. The samples [boot swabs (n = 612), wall swabs (n = 612), feed (n = 400), and water (n = 411)] were analyzed for the presence of NTS, following standard methods. Identification and antimicrobial susceptibility testing of the NTS isolates were done using the BD Bruker IVD MALDITOF and the BD Phoenix M50 analyzers, respectively. Results: NTS was found in 46.4% (26/56) of the poultry farms and 14.5% (89/612) of the henhouses, with an overall prevalence of 54.2%. The prevalence of Salmonella positivity in Kumasi was high compared to Accra (OR = 1.67; 95% CI = 1.07–2.61; p = 0.023) and in broiler vs. layers (OR = 1.89; 95% CI = 1.03–3.47; p = 0.039). An inverse relationship was found between the farm size and for farms >2500 chickens (OR = 0.41; 95% CI = 0.20–0.85; p = 0.017) and 650–2500 chickens (OR = 0.56; 95% CI = 0.27–1.13; p = 0.109). The AMR across rates were as follows; tetracycline (67.2%, n = 84), nalidixic acid (64%, n = 80), trimethoprim-sulfamethoxazole (46.1%, n = 59), ciprofloxacin (39.8%, n = 51), gentamicin (35.9%, n = 46), amoxicillin-clavulanate (32.8%, n = 42), ampicillin (27.3%, n = 35), levofloxacin and cefazolin (18% each, n = 23), azithromycin (3.2%, n = 4), and chloramphenicol (0%, n = 0). Moreover, 64% (n = 80) of the NTS were multidrug-resistant. Conclusion: The prevalence of non-typhoidal Salmonella appears to be high among poultry in Ghana, as is multidrug resistance of NTS. This underscores the need for continuous surveillance of AMR and its drivers among poultry and other livestock in the country.