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.

Background: Antimicrobial resistance (AMR) poses a serious global threat to human and animal health. In the context of antimicrobial usage (AMU) in livestock production, veterinarians are key stakeholders. However, there is a lack of comprehensive situational analysis regarding the current Knowledge, Attitudes, and Practices (KAP) among veterinarians concerning AMU and AMR in poultry production in Nepal.Methods: The primary objective of this study was to evaluate the situation of AMU and KAP regarding AMU and AMR of among poultry practitioner veterinarians in Nepal. A total of 327 respondents from 56 districts across seven provinces participated. Demographic information and AMU situation were collected and analyzed using descriptive statistics, and factors affecting KAP on AMU and AMR were performed using logistic regression analysis.Results: Nearly half of veterinarians (49.2%) were from Bagmati, followed by Lumbini (16.5%) and Gandaki (8.9%) provinces. Most of the respondents (85.0%) identified themselves as male with a mean age of 31.9 ± 7.8 years, with a range of 24–74 years. A large proportion of veterinarians held a master’s degree (43.8%). Regarding reasons for AMR, 51.1% of them attributed it to the irrational use of antimicrobials. Other identified reasons for AMR, including over-the-counter sales (27.8%), low-dose administration (12.3%), and low-quality antimicrobials (6.7%). Based on antibiotic prescription rates, most veterinarians (50.8%) prescribed antimicrobials at a rate of 20–40%, while 25.9% prescribed at a rate of less than 20.0 and 18.9% at a rate of 40–60%. Approximately 89.0% of veterinarians agreed that vaccination could reduce the use of antimicrobials in poultry, and 75.6% preferred narrow-spectrum antimicrobials than broad-spectrum antimicrobials. A combination of broad-spectrum antimicrobials such as colistin with amoxicillin, gentamicin, tylosin, and tetracycline was commonly used in poultry production.Discussion: In logistic regression analysis, it was observed that veterinarians aged 45–60 years demonstrated significantly higher levels of knowledge concerning AMU and AMR (p = 0.02) compared to those in the 24–30 age group. This study indicates that the need for robust regulatory mechanisms in veterinary drug administration and increased awareness among veterinarians to address the AMR issue livestock production.

The purpose of this study was twofold: first, to conduct a situational analysis, and second, to assess the knowledge, attitudes, and practices (KAP) of broiler poultry farmers (BPF) regarding antimicrobial use (AMU) and antimicrobial resistance (AMR). Data were collected from 500 BPF across 40 districts, representing 88.1% of Nepal’s broiler poultry population. Among these farmers, 81.0% were male, 59.6% had up to 4 years of experience in poultry farming, and 50.8% had completed at least a high school education. The most used antimicrobials on the farms were doxycycline (23.5%), neomycin (17.1%), and colistin sulfate (9.6%) out of 27 reported antimicrobials. While the BPF exhibited limited knowledge (62.6%) and practice (55.5%) related to AMU and AMR, their overall attitude toward these issues was positive (91.6%). This study also identified significant factors influencing farmers’ attitudes toward AMU and AMR. Farmers aged 31–40 showed a stronger inclination compared to other age groups (OR = 4.2, p = 0.02), and those using antimicrobials for preventive purposes had a more favorable attitude compared to those using them for other purposes (OR = 5.9, p = 0.02). In light of these findings, this study recommends the implementation of effective regulatory measures for drug usage, along with awareness programs addressing AMU and AMR to address the issue of AMR in poultry production.

Foot and mouth disease (FMD) is endemic in Nepal and significantly impacts the livelihood of farmers, national economy, and trade of Nepal. However, outbreak investigations are not frequently conducted, and there have been limited studies to understand the associated risk factors. A case-control study was performed in dairy cattle farms of Shankharapur and Kageshwari Municipalities, Kathmandu from March to April 2020 to describe the outbreak and identify the risk factors associated with FMD. There were 31 case farms, while 62 farms were selected as control farms (1:2). The information from case and control farms was collected by semi-structured questionnaire survey through field visits and observations. The univariable and multivariable logistic regressions were performed. The farm-level prevalence of FMD was 25.2% (n=31/123). Among the FMD affected farms, the proportion of positive farms in Shankharapur (61.3% (19/31)) was significantly higher than Kageshwori (38.7% (12/31)). The final multivariable logistic regression analysis identified four variables: cattle purchased within 14 days (OR=12.9; CI=2.4-69.5), milk market distance less than two kilometers from the farm (OR=32.7; CI=5.8-186.3), sharing of the bull from other farms for natural insemination (OR=5.7; CI=1.2-26.8), and no vaccination against FMD in the past six months (OR=19.1; CI=2.0-186.2) as significant risk factors for the occurrence of FMD. This study suggests farmers vaccinate their dairy cattle with FMD vaccine as per the vaccination schedule suggested by the veterinarians, practice quarantine measures when new animals are introduced to their farms, practice biosecurity measures in their farms, and do not use bulls from areas where there are ongoing FMD outbreaks.

Background: Commercial hatcheries play an important role in the overall poultry value chain-providing small to large poultry farmers with day old chicks. Any outbreak in such hatcheries can spread diseases to other farms. Regular screening of major avian pathogens, along with strict bio-security measures, can prevent spread of diseases in hatcheries. Newcastle Disease Virus (NDV), Infectious Bronchitis Virus (IBV), Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), Infectious Bursal Disease Virus (IBDV) and Influenza A Virus (IAV) are among the most prevalent poultry diseases which can be detected in egg albumin. Method: We retrospectively (August 2020-August 2021, except October 2020) analyzed diagnostic results for six selected avian pathogens (NDV, IBV, MS, MG, IBDV and IAV) on eggs (n=4343) received from eleven major commercial poultry hatcheries located in the five adjoining districts of Kathmandu, Nepal. Albumin from 10% randomly selected eggs from each hatchery were tested for the six avian pathogens using multiplex PCR. Result: Majority (7/11, 64%) of the poultry hatcheries had at least one of the six pathogens present. We detected at least one avian pathogen in nine out of eleven months (82%) of screening. Except for IBDV, we found one or more of the other major avian pathogens-Influenza A (IAV) (n=4 times) and Mycoplasma gallisepticum (MG) ( n=4 times) were detected the most, followed by Newcastle Virus (NDV) (n=3 times). Infectious bronchitis virus (IBV) were detected twice, and Mycoplasma synoviae (MS) was detected once. Conclusion: In a resource strapped country like Nepal, poultry disease outbreak investigation in particular and surveillance in general are challenging. Meanwhile, poultry production is highly impacted by disease outbreaks often triggered by poor bio-security and lack of pathogen screening practices. Our molecular screening tests have picked up major poultry pathogens present throughout the year in eggs collected from hatcheries. Influenza A was detected at 4 different incidences throughout the year, which is of concern to both human and animal health. Quick systematic screening of eggs at key distribution points (hatcheries) for major avian pathogens is an effective surveillance tool for early disease detection and containment of outbreaks.