Aeromonas hydrophila is a common zoonotic agent in aquatic environments that causes gastroenteritis and wound infections in both humans and animals through foodborne and hospital-acquired infection. Antimicrobial resistance (AMR) combination with virulence factors enhances treatment challenging. The prevalence and AMR of Aeromonas hydrophila have been increasingly reported, posing a significant threat to both animal and public health. This systematic review and meta-analysis aimed to determine the prevalence of A. hydrophila and its resistance to aquatic food animals. A comprehensive search for relevant studies was conducted on Google Scholar, PubMed, ScienceDirect, and Scopus, following the PRISMA guidelines, covering studies from January 2020 to December 2024. The quality of the included publications was evaluated using the Joanna Briggs Institute critical appraisal tool. Differences in the prevalence and AMR of A. hydrophila were assessed using a random-effect model. A total of 14,077 studies were screened, and 14 publications were included. Bacterial isolation of A. hydrophila was achieved using various standard protocols, involving culture on Rimler-Shotts (RS) agar and Tryptic Soy Agar (TSA), with or without antimicrobials. Subsequent biochemical identification confirmed the isolates. The pool prevalence of A. hydrophila (30.7%, 95% C.I.:17.0-46.3%), and the distribution of virulence genes were 71.2%. The most common resistance observed to penicillin (80.7%), oxytetracycline (69.9%) and macrolides (67.8%). The most prevalent AMR genes identified were bla _TEM (67.0%), followed by tetA (63.7%). The increasing presence of A. hydrophila in aquaculture suggests a considerable risk of disease. The prevalence of both A. hydrophila and AMR was higher in Africa than in Asia, indicating regional variations in the AMR pattern. However, monitoring and surveillance of A. hydrophila remained limited. A major limitation of this study was the heterogeneity in effect estimates across the selected studies. Nonetheless, the quality assessment conducted indicated that this variability did not compromise the consistency or reliability of the findings.

Colistin (CST) is considered the last resort for the treatment of infectious diseases due to multidrug-resistant bacteria. Since the mcr-1 gene has been reported in Enterobacteriaceae isolated from food, animals, and humans in China, the prevalence of CST-resistant bacteria has been of great concern. Here, we investigated the prevalence of CST resistance and plasmid-mediated colistin-resistance genes (mcr) in gram-negative bacteria isolated among retail meats in Japan. CST-resistant bacteria were isolated from 310 domestic retail meats (103 chicken meat, 103 pork, and 104 beef) purchased between May 2017 and July 2018 from retail shops in Japan using CST-containing media and antimicrobial susceptibility testing. The mcr gene was investigated in isolates with a CST minimum inhibitory concentration of ≥1 μg/mL. Excluding the intrinsically CST-resistant isolates, CST-resistant bacteria were isolated from 39 of the total chicken meats (37.9%), 19 of the pork samples (18.4%), and 18 of the beef samples (17.3%). A total of 459 isolates were identified, out of which 99 were CST-resistant. CST resistance (resistance breakpoints: Aeromonas, >4 μg/mL; others, >2 μg/mL) was found in Aeromonas spp. (48/206, 23.3%), Yersinia spp. (5/112, 4.5%), Escherichia coli (23/39, 59%), Citrobacter spp. (4/26, 15.4%), Klebsiella spp. (2/23, 8.7%), Raoultella spp. (2/16, 12.5%), Enterobacter spp. (7/14, 50%), Pseudomonas spp. (1/8, 12.5%), Pantoea spp. (5/7, 71.4%), Ewingella spp. (1/4, 25%), and Kluyvera spp. (1/2, 50%). The mcr gene was detected in 16 isolates: mcr-1 in 14 isolates of E. coli from 10 chicken samples (9.7%), and mcr-3 in two isolates of Aeromonas sobria from pork and chicken samples (each 1.0%). The findings of this study highlight the necessity of surveillance of CST resistance and resistance genes in bacteria that contaminate retail meats.

This systematic review and meta-analysis investigates the prevalence of Vibrio parahaemolyticus, its virulence factors, antimicrobial resistance (AMR), and its resistance determinants in shrimp. This study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, to identify and select relevant peer-reviewed articles published between January 2020 and December 2022. The search strategy involved multiple online databases, including Google Scholar, PubMed, ScienceDirect, and Scopus. The inclusion criteria focused on studies that examined V. parahaemolyticus prevalence, virulence factors, and AMR in shrimp from farms to retail outlets. A total of 32 studies were analyzed, revealing a pooled estimate prevalence of V. parahaemolyticus in shrimp at 46.0%, with significant heterogeneity observed. Subgroup analysis highlighted varying prevalence rates across continents, emphasizing the need for further investigation. Virulence factor analysis identified thermostable direct hemolysin (tdh) and tdh-related hemolysin (trh) as the most common. Phenotypic AMR analysis indicated notable resistance to glycopeptides, nitrofurans, and beta-lactams. However, the correlation between antimicrobial usage in shrimp farming and observed resistance patterns was inconclusive. Funnel plots suggested potential publication bias, indicating a need for cautious interpretation of findings. This study underscores the urgency of coordinated efforts to address AMR in V. parahaemolyticus to safeguard public health and to ensure sustainable aquaculture practices.

Resistance to antimicrobial agents is a growing concern in public health. It has been reported in wildlife from several places in the world though wild animals are not normally exposed to clinically used antimicrobial agents. Despite this, very little research has been done in Ghana to determine antimicrobial resistance in wild animals, particularly those in protected areas. In this study, the presence of colistin resistant and multidrug resistant (MDR) gram-negative bacteria in cloacal swabs of wild birds captured in a Ghanaian forest protected area were evaluated. A total of 195 isolates from 138 individual birds were obtained, identified and tested for resistance to colistin. The colistin-resistant isolates were subsequently tested for multidrug resistance to 4 other antimicrobial agents (Oxytetracycline, Streptomycin, Ampicillin and Ciprofloxacin). Colistin resistance was observed in 6.5% (9/138) of the birds and this was seen in only birds that were sampled close to the reception area of the protected area. About 50% of the colistin-resistant isolates were multidrug resistant. AMR isolates were obtained from birds that have been documented to show an insectivorous or omnivorous feeding preference. Data obtained from the study suggests that AMR and MDR occurred in wild birds from the Conservation Area and supports the claim that proximity to human impacted habitats (settlements/farmlands) increased the likelihood of carriage of AMR. Though the routes of transmission remain unclear, there is potential for spread from the wild birds to other wild/domestic animals and possibly back to humans.

Antimicrobial-resistant (AMR) bacteria affect human and animal health worldwide. Here, CTX-M-14-producing Escherichia coli isolates were isolated from Siberian weasels (Mustela sibirica) that were captured on a veterinary campus. To clarify the source of bacteria in the weasels, we examined the domestic animals reared in seven facilities on the campus. Extended-spectrum β-lactamase (ESBL)-producing E. coli were isolated on deoxycholate hydrogen sulfide lactose agar, containing cephalexin (50 μg/mL) or cefotaxime (2 μg/mL), and were characterized with antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), replicon typing, and β-lactamase typing analyses. Next-generation sequencing of the ESBL-encoding plasmids was also performed. CTX-M-14 producers isolated from both domestic animals and weasels were classified into six clusters with seven PFGE profiles. The PFGE and antimicrobial resistance profiles were characterized by the animal facility. All CTX-M-14 plasmids belonged to the IncI1 type with a similar size (98.9–99.3 kb), except for one plasmid that was 105.5 kb in length. The unweighted pair group method with arithmetic mean (UPGMA) revealed that the CTX-M-14 plasmid in the weasel isolates might have the same origin as the CTX-M-14 plasmid in the domestic animals. Our findings shed further light on the association of antimicrobial resistance between wild and domestic animals.