VM2001_AMR_2025

The causes of AMR include:

1. Overuse of antibiotics in humans and animals, leading to selective pressure on bacteria.
2. Inappropriate prescribing practices, where antibiotics are given for viral infections.
3. Agricultural practices, such as using antibiotics for growth promotion in livestock.
4. Poor infection prevention and control measures in healthcare settings.
5. Global travel and trade, which facilitate the spread of resistant strains.
6. Environmental factors, including contamination of water sources with antibiotics and resistant bacteria.

The effects of AMR on food security include:

• Increased foodborne illnesses due to resistant pathogens, leading to higher healthcare costs.
• Reduced effectiveness of treatments for infections in both humans and animals, resulting in longer recovery times.
• Economic losses in agriculture due to decreased livestock productivity and increased mortality rates.
• Trade restrictions on food products from regions with high AMR prevalence, affecting market access.
• Threats to public health, as resistant bacteria can spread from animals to humans through the food chain.

Mechanisms of AMR development include:

1. Genetic mutations in bacteria that confer resistance.
2. Horizontal gene transfer, where resistant genes are shared between bacteria.
3. Biofilm formation, which protects bacteria from antibiotic action.
4. Efflux pumps, which expel antibiotics from bacterial cells.
5. Enzymatic degradation of antibiotics, rendering them ineffective.
6. Alteration of target sites within bacteria, preventing antibiotics from binding effectively.

Strategies to combat AMR in Hong Kong and Asia include:

• Strengthening regulations on antibiotic use in agriculture and healthcare.
• Promoting responsible prescribing practices among healthcare providers.
• Enhancing surveillance systems to monitor AMR trends and outbreaks.
• Public education campaigns to raise awareness about AMR and its consequences.
• Investment in research for new antibiotics and alternative therapies.
• Collaboration between sectors, including human health, veterinary medicine, and environmental health, to adopt a One Health approach.

Antimicrobials are medicines used to prevent and treat infections in humans, animals, and plants. They include:

• Antibiotics
• Antivirals
• Antifungals
• Antiparasitics

Antimicrobial Resistance (AMR) occurs when bacteria, viruses, fungi, and parasites change over time and no longer respond to medicines. This makes infections harder to treat and increases the risk of disease spread, severe illness, and death. As a result of AMR, antimicrobials become ineffective, leading to infections that are increasingly difficult or impossible to treat.

Antimicrobial resistance (AMR) refers to the ability of microorganisms, such as bacteria, to resist the effects of medications that once effectively treated them. In the case of tuberculosis (TB), caused by Mycobacterium tuberculosis, AMR is particularly concerning due to the emergence of multidrug-resistant strains. These strains limit treatment options and are responsible for approximately half a million infections annually.

ESCAPE refers to a group of pathogens that are of high concern due to their increasing resistance to antibiotics. The pathogens included in this group are:

1. Enterococcus faecium
2. Staphylococcus aureus
3. Clostridioides difficile
4. Acinetobacter baumannii
5. Pseudomonas aeruginosa
6. Enterobacter spp.

AMR threatens progress in healthcare, food production, and life expectancy. It is associated with an estimated 4.9 million deaths in 2019, including 1.3 million deaths directly caused by AMR bacteria.

AMR significantly affects productivity due to prolonged hospital stays and the need for more expensive and intensive care, leading to substantial costs for national economies and health systems.

Low-income countries are estimated to lose approximately 5% of their GDP due to the impact of AMR on food and agriculture production.

AMR can disrupt the balance of the microbial community in soil, affecting the nutrient cycling process, and alter the composition of the microbial community in the aquatic ecosystem, disrupting the food web.

In 2019, an estimated 4 million human deaths were linked to antimicrobial resistance, with 1.3 million of those deaths directly caused by resistant bacteria.

By 2050, it is projected that there will be 10,000,000 human deaths due to antimicrobial resistance.

Whenever there is a high number of bacteria, few of them are resistant to antibiotics.

Antibiotics kill the bacteria that cause the illness, as well as good bacteria that protect the body from infection.

The resistant bacteria can now grow and multiply without competition.

Some bacteria can even transfer their resistance to antibiotics to other bacteria, which causes more problems.

Intrinsic resistance is the innate ability of bacteria to resist a class of antibiotics without any prior exposure or genetic change.

Acquired resistance occurs when a naturally susceptible microorganism develops the ability to resist the effects of an antibiotic. This can happen through:

1. Horizontal gene transfer - transfer of genetic material between bacteria.
2. Vertical gene transfer - passing genetic material from parent to offspring during replication and cell division.

Acquired resistance can occur through:

Bacterial conjugation involves the transfer of genetic material from a donor cell (F+ cell) to a recipient cell (F- cell) through a structure called a pilus. This process results in the recipient cell becoming a new F+ cell, which can contribute to genetic diversity and the spread of traits such as antibiotic resistance among bacterial populations.

Bacterial transformation occurs when a live bacterial cell takes up DNA fragments from a dead bacterial cell. These fragments are then integrated into the genome of the live cell, resulting in a transformed cell that may exhibit new traits, including potential antibiotic resistance.

Bacterial transduction is the process by which a virus infects a bacterial cell, leading to the incorporation of viral DNA and bacterial DNA fragments into new virions. When these virions infect a recipient cell, they can introduce new genetic material, resulting in a transduced cell that may acquire new characteristics, including antibiotic resistance.

Bacteria develop antimicrobial resistance through the following mechanisms:

1. Limiting uptake of a drug: The cell wall is modified to reduce the entry of antibiotics (Impermeability).
2. Modification of a drug target: The antibiotic target is altered to reduce its affinity for the antibiotic (Modification).
3. Active efflux of a drug: An efflux pump actively removes the antibiotic from the cell (Pumping out).
4. Inactivation of a drug: The antibiotic is chemically modified to inactivate it (Inactivation).

1. Impenetrability: Modified cell wall proteins block antibiotics from entering the cell.

2. Modification: Altered drug targets inside the cell prevent antibiotics from binding.

3. Pumping out: Increased active efflux pumps expel antibiotics from the cell.

4. Inactivation: Addition of a phosphate group to antibiotics reduces their ability to bind to bacterial ribosomes.

• Inappropriate Use of Antibiotics: 80% of hospitalized patients receive antibiotics, often without a physician's prescription.
• Lack of Water, Sanitation, and Hygiene (WASH): Poor infrastructure contributes to the spread of infections.
• Lack of Hygiene and Infection Prevention: Insufficient strategies to control infections lead to increased AMR.

• Inappropriate Use of Antibiotics: Misuse in livestock and fish, including therapeutic and prophylactic use as growth promoters.
• Human Factors: Refugees, travelers, and individuals with immunosuppressive diseases may contribute to AMR spread.
• Access to Healthcare: Inequities in healthcare access can exacerbate AMR issues.

• Population density and overcrowding
• Poor sanitation
• Increased community-acquired resistance
• Ineffective infection control programs
• Increasing national and international travel
• Widespread use of antibiotics in animal husbandry and agriculture

• Quality of the antimicrobials
• Misuse of antimicrobials
• Over-the-counter availability of antimicrobials
• Irrational fixed dose/combination of antimicrobials
• Substandard antimicrobials causing suboptimal blood concentration

• Poor adherence to dosage regimens
• Poverty
• Lack of sanitation concepts
• Lack of education
• Self-medication
• Misconceptions

• Inappropriate use of available drugs
• Increased empiric poly-antimicrobial use
• Overuse of antimicrobials
• Inadequate dosing
• Lack of current knowledge and training

1. Improve overall coordination
2. Improve regulatory framework
3. Reduce the need for and promote prudent use of antibiotics
4. Improve surveillance
5. Advocate and communicate
6. Build capacity and provide training
7. Address knowledge gaps and research needs

The Global Action Plan on Antimicrobial Resistance (GAP) is a strategic framework aimed at combating AMR through coordinated global efforts, promoting responsible use of antimicrobials, and enhancing surveillance and research.

World Antimicrobial Awareness Week (WAAW) aims to raise awareness about AMR and promote best practices among the public, health professionals, and policymakers to prevent the further emergence and spread of AMR.

The Tripartite Joint Secretariat on Antimicrobial Resistance, consisting of the FAO, OIE, and WHO, collaborates to address AMR through a One Health approach, integrating human, animal, and environmental health.

The Global Antimicrobial Resistance and Use Surveillance System (GLASS) is a WHO initiative that collects and analyzes data on AMR and antimicrobial use globally to inform policy and action.

Global research and development priority setting for AMR is crucial for identifying and addressing the most pressing needs in AMR research, ensuring effective interventions and innovations are developed to combat AMR.

The six key areas are:

1. Strengthen knowledge through surveillance and research;
2. Optimise use of antimicrobials in humans and animals;
3. Reduce incidence of infection through effective sanitation, hygiene, and preventive measures;
4. Improve awareness and understanding of AMR through effective communication, education, and training;
5. Promote research on AMR; and
6. Strengthen partnerships and foster engagement of relevant stakeholders.

Two-thirds of all medically important antibiotics continue to be sold for use in livestock production, with many uses being unnecessary.

The total livestock use of antibiotics is 65%, while human use is 35%.

Antimicrobial use in animals contributes to antimicrobial resistance (AMR) in animals, which can then affect humans through various pathways:

1. Foodborne transmission: Resistant bacteria can be transferred to humans through contaminated food products.
2. Manure: Manure from treated animals can contaminate the environment, leading to the spread of resistant bacteria.
3. Environmental contamination: Resistant bacteria can enter water systems and affect crops.
4. Occupational exposure: People working with animals may be exposed to resistant bacteria.

Ultimately, these pathways lead to a fraction of AMR in humans being attributable to antimicrobial use in animals.

Antibiotic resistance spreads through the following process:

1. Farm animals receive antibiotics, leading to the development of antibiotic-resistant bacteria.
2. These resistant bacteria can contaminate fertilizer or water, which is then used on food crops.
3. Contaminated crops can transfer resistant bacteria to humans when consumed.
4. Additionally, meat products that are not handled or cooked properly can also transfer resistant bacteria to humans.

This cycle illustrates the interconnectedness of animal health, food safety, and human health.

Veterinarians can implement the following strategies to combat AMR:

1. Prevention of infectious diseases
2. Cleaning and sanitising hands and equipment
3. Maintaining accurate records of treatments and outcomes
4. Adequate selection of antibiotics when needed
5. Preventing environmental contamination
6. Keeping knowledge up-to-date
7. Promoting and engaging with good practices for diagnostics and treatment among colleagues and clients

The key components include:

1. Wildlife: Diet, life history, sociality, and migration.
2. Air: Various atmospheric factors.
3. Waste: Rubbish, sewage, and manure.
4. Livestock and Humans: Antibiotic use, diet, travel, and sociality.
5. Land: Soil, dust, sediment, crops, and wild plants.
6. Water: Rivers, seas, estuaries, reservoirs, boreholes, streams, and lakes.

Environmental Metadata includes:

• Heavy metals: Level and bioavailability.
• Antimicrobial compounds: Indices of levels, types, characteristics, sales, prescription rates, and concentrations in wastes.
• Environmental factors: Weather, land use, water flow and temperature, flooding, pollution, geology and soil type, and habitat characteristics.

The AMR metric is an index of bacteria expressing AMR phenotype in the environment, which includes:

• Genotypes
• Counts and concentrations of Antimicrobial Resistance Genes (ARGs)
• Plasmids metagenomes
• Bacterial strain

The number of sites recruited to compile the data is limited, as noted by WHO in 2017.

The sites have access to human data only.

AMR data from animal and environmental sources are limited.

The focus is primarily on farm animals.