Economic assessment of an intervention strategy to reduce antimicrobial usage in small-scale chicken farms in Vietnam.

Antimicrobials are a core aspect of most livestock production systems, especially in low-and middle-income countries. They underpin the efficient use of scarce feed resources and stabilize returns on capital and labor inputs. Antimicrobial use (AMU) contributes to the production of healthy animals, yet AMU in livestock is linked to antimicrobial resistance (AMR) in animals, humans and the environment.

A review and meta-analysis of non-typhoidal in Vietnam: Challenges to the control and antimicrobial resistance traits of a neglected zoonotic pathogen.

Non-typhoidal (NTS) is a food-borne zoonotic pathogen with important implications for human health. Despite its importance, the burden of NTS infections in Vietnam is unknown. We conducted a systematic review and a meta-analysis to describe the prevalence and phenotypic antimicrobial resistance (AMR) for NTS over time in Vietnam.

Molecular characterization of Campylobacter spp. isolates obtained from commercial broilers and native chickens in Southern Thailand using whole genome sequencing.

Chickens are the primary reservoirs of Campylobacter spp., mainly C. jejuni and C.

The characterization and correlation between the phenotypic and genotypic resistance of spp isolates from commercial broilers and native chickens in the south of Thailand.

High prevalence in chickens; more prevalent than .Susceptibility to macrolides but resistance to quinolones/tetracyclines in isolates.Homogeneous resistance patterns within farms; higher in broilers than in native birds.

A systematic review and meta-analysis of integrated studies on antimicrobial resistance in Vietnam, with a focus on , from a One Health perspective.

Vietnam is a low- and middle-income country (LMIC), a primary food producer, and an antimicrobial resistance (AMR) hotspot. AMR is recognized as a One Health challenge since it may transfer between humans, animals and the environment. This study aimed to apply systematic review and meta-analysis to investigate the phenotypic profiles and correlations of antimicrobial-resistant across three compartments: humans, animals and the environment in Vietnam.

Impact of Freeze Storage on the Estimation of Phenotypic Antimicrobial Resistance Prevalence in Collected from Faecal Samples from Healthy Humans and Chickens.

Many studies on phenotypic antimicrobial resistance (AMR) of bacteria from healthy populations are conducted on freeze-stored samples. However, the impact of this practice on phenotypic AMR is not known. We investigated the prevalence of phenotypic AMR in from chicken ( = 10) and human ( = 11) faecal samples collected from healthy subjects, subject to freeze storage (-20 °C and -80 °C) for 1, 2, 3, and 6 months.

Antimicrobial resistance in commensal from humans and chickens in the Mekong Delta of Vietnam is driven by antimicrobial usage and potential cross-species transmission.

Objectives: To investigate phenotypic antimicrobial resistance (AMR) in relation to antimicrobial use (AMU) and potential inter-species transmission among from humans and chickens located in the same households in the Mekong Delta of Vietnam.

Methods: We collected data on AMU and faecal swabs from humans (= 426) and chickens (= 237) from 237 small-scale farms. From each sample, one strain was isolated and tested for its susceptibility against 11 antimicrobials by Sensititre AST.

Modelling the impact of antimicrobial use and external introductions on commensal E. coli colistin resistance in small-scale chicken farms of the Mekong delta of Vietnam.

Colistin is a critically important antimicrobial for human medicine, and colistin-resistant Escherichia coli are commonly found in poultry and poultry products in Southeast Asia. Here, we aim at disentangling the within-farm and outside-farm drivers of colistin resistance in small-scale chicken farms of the Mekong delta of Vietnam. Nineteen Vietnamese chicken farms were followed up along a whole production cycle, during which weekly antimicrobial use data were recorded.

Minimum inhibitory concentrations of commercial essential oils against common chicken pathogenic bacteria and their relationship with antibiotic resistance.

Aims: We investigated the antibacterial effect of seven essential oils (EOs) and one EO-containing liquid phytogenic solution marketed for poultry and pigs ('Product A') on chicken pathogens, as well as the relationship between minimum inhibitory concentration (MIC) in EOs and antibiotics commonly administered to chicken flocks in the Mekong Delta (Vietnam).

Methods And Results: Micellar extracts from oregano (Origanum vulgare), cajeput (Melaleuca leucadendra), garlic (Allium sativum), black pepper (Piper nigrum), peppermint (Mentha × piperita L.), tea tree (Melaleuca alternifolia), cinnamon (Cinnamomum zeylanicum) EOs and Product A were investigated for their MIC against Avibacterium endocarditidis (N = 10), Pasteurella multocida (N = 7), Ornitobacterium rhinotracheale (ORT) (N = 10), Escherichia coli (N = 10) and Gallibacterium anatis (N = 10).

Small-scale commercial chicken production: A risky business for farmers in the Mekong Delta of Vietnam.

Small-scale farming of meat chicken flocks using local native breeds contributes to the economy of many rural livelihoods in Vietnam and many other low- and middle-income countries (LMICs). These systems are also the target of high levels of antimicrobial use (AMU); however, little is known about the profitability and sustainability of such systems. Since small-scale farms are commercial enterprises, this knowledge is essential to develop successful strategies to curb excessive AMU.

Feasibility study of a field survey to measure antimicrobial usage in humans and animals in the Mekong Delta region of Vietnam.

Background: Development of antimicrobial use (AMU) surveillance systems in humans and animals is a priority for many low- and middle-income countries; however accurate estimations are hampered by a diversity of animal production systems and metrics. The Mekong Delta region of Vietnam is a 'hotspot' of antimicrobial resistance and is home to a high density of humans and animal populations.

Objectives: To measure and compare AMU using different metrics (standing population, biomass and population correction unit) in the Mekong Delta, and to explore the potential of field-based data collection methods in the design of AMU surveillance systems.

Effects of prophylactic and therapeutic antimicrobial uses in small-scale chicken flocks.

Antimicrobials are extensively used both prophylactically and therapeutically in poultry production. Despite this, there are little data on the effect of antimicrobial use (AMU) on disease incidence rate and per cent mortality. We investigated the relationships between AMU and disease and between AMU and mortality using data from a large (n = 322 flocks) cohort of small-scale chicken flocks in the Mekong Delta, Vietnam, that were followed longitudinally from day old to slaughter (5,566 observation weeks).

Antimicrobial use through consumption of medicated feeds in chicken flocks in the Mekong Delta of Vietnam: A three-year study before a ban on antimicrobial growth promoters.

Antimicrobials are included in commercial animal feed rations in many low- and middle-income countries (LMICs). We measured antimicrobial use (AMU) in commercial feed products consumed by 338 small-scale chicken flocks in the Mekong Delta of Vietnam, before a gradual nationwide ban on prophylactic use of antimicrobials (including in commercial feeds) to be introduced in the country over the coming five years. We inspected the labels of commercial feeds and calculated amounts of antimicrobial active ingredients (AAIs) given to flocks.

Reducing Antimicrobial Usage in Small-Scale Chicken Farms in Vietnam: A 3-Year Intervention Study.

Indiscriminate antimicrobial use (AMU) in animal production is a driver of antimicrobial resistance globally. There is a need to define sustainable interventions to reduce AMU in small-scale production systems, which currently represent the most widespread farming systems in South East Asia and many low- and middle-income countries. We conducted a before-and-after intervention study on a random sample of small-scale chicken farms in the Mekong Delta of Vietnam from 2016 to 2019.

A novel method for measuring phenotypic colistin resistance in populations from chicken flocks.

Colistin is extensively used in animal production in many low- and middle-income countries. There is a need to develop methodologies to benchmark and monitor changes in resistance among mixed commensal bacterial populations in farms. We aimed to evaluate the performance of a broth microdilution method based on culturing a pooled suspension (30-50 organisms) obtained from each sample.

The role of animals as a source of antimicrobial resistant nontyphoidal Salmonella causing invasive and non-invasive human disease in Vietnam.

Background: Nontyphoidal Salmonella (NTS) are associated with both diarrhea and bacteremia. Antimicrobial resistance (AMR) is common in NTS in low-middle income countries, but the major source(s) of AMR NTS in humans are not known. Here, we aimed to assess the role of animals as a source of AMR in human NTS infections in Vietnam.

Characterizing Antimicrobial Resistance in Chicken Pathogens: A Step towards Improved Antimicrobial Stewardship in Poultry Production in Vietnam.

In the Mekong Delta of Vietnam, farmers use large quantities of antimicrobials to raise small-scale chicken flocks, often including active ingredients regarded of "critical importance'" by the World Health Organization. Due to limitations in laboratory capacity, the choice of antimicrobials normally does not follow any empirical criteria of effectiveness. The aim of this study was to highlight non-critically important antimicrobials against which chicken pathogens are likely to be susceptible as a basis for treatment guidelines.

Differential antimicrobial susceptibility profiles between symptomatic and asymptomatic non-typhoidal infections in Vietnamese children.

Non-typhoidal Salmonella (NTS) serovars, sequences types and antimicrobial susceptibility profiles have specific associations with animal and human infections in Vietnam. Antimicrobial resistance may have an effect on the manifestation of human NTS infections, with isolates from asymptomatic individuals being more susceptible to antimicrobials than those associated with animals and human diarrhoea.

Carriage of the zoonotic organism Streptococcus suis in chicken flocks in Vietnam.

Streptococcus suis infections are an emerging zoonotic agent causing severe disease in humans and a major pig pathogen worldwide. We investigated the colonization of S. suis in healthy chickens in different flocks (n = 59) as well as in-contact pigs in farms with S.

An estimation of total antimicrobial usage in humans and animals in Vietnam.

The accurate assessment of antimicrobial use (AMU) requires relating quantities of active ingredients (AAIs) with population denominators. These data can be used to prioritize potential sources of selective pressure for antimicrobial resistance and to establish reduction targets. Here, we estimated AMU in Vietnam (human population 93.