Antimicrobial resistance

20 February 2018

Many of the medical breakthroughs of the last century could be lost through the spread of antimicrobial resistance. Previously curable infectious diseases may become untreatable and spread throughout the world. This has already started to happen.

The report “Antimicrobial resistance: global report on surveillance 2014” showed that antimicrobial resistance is everywhere and has the potential to affect anyone, of any age, in any country.

In April 2015, WHO published a “Worldwide country situation analysis: Response to antimicrobial resistance”. It revealed that while much activity is underway and many governments are committed to addressing the problem, there are major gaps in actions needed across all 6 WHO regions.

This fact file describes the threat of drug resistance, some of its main causes, and how WHO is helping to lead the global response.

WHO/A. Loke

What is antimicrobial resistance?

Antimicrobial resistance is the ability of a microorganism (like bacteria, viruses, and some parasites) to stop an antimicrobial (such as antibiotics, antivirals and antimalarials) from working against it. As a result, standard treatments become ineffective, infections persist and may spread to others.

WHO/Q. Mattingly

Drug resistance is a global problem

Over the past years, the use and misuse of antimicrobials has increased the number and types of resistant organisms. Consequently many infectious diseases may one day become uncontrollable. With the growth of global trade and travel, resistant microorganisms can spread promptly to any part of the world.

CDC

What causes drug resistance?

Drug resistance is a natural evolutionary phenomenon. When microorganisms are exposed to an antimicrobial, the more susceptible organisms succumb, leaving behind those resistant to the antimicrobial. They can then pass on their resistance to their offspring.

WHO/M. Edwards

Inappropriate use of medicines worsens drug resistance

Inappropriate use of antimicrobials drives the development of drug resistance. Both overuse, underuse and misuse of medicines contribute to the problem. Ensuring that patients are informed about the need to take the right dosage of the right antimicrobial requires action from prescribers, pharmacists and dispensers, pharmaceutical industry, the public and patients, as well as the policy makers.

WHO/Sergey Volkov

Lack of quality medicines contributes to drug resistance

Most drug quality assurance systems are weak. This can lead to poor quality medicines, exposing patients to sub-optimal concentrations of antimicrobials, thus creating the conditions for drug resistance to develop. In some countries poor access to antimicrobials forces patients to take incomplete courses of treatment or to seek alternatives that could include substandard medicines.

WHO/J. Perugia

Animal husbandry is a source of resistance to antibiotics

Sub-therapeutic doses of antibiotics are used in animal-rearing for promoting growth or preventing diseases. This can result in resistant microorganisms, which can spread to humans.

WHO/P. Bagla

Poor infection prevention and control amplifies drug resistance

Poor infection prevention and control can increase the spread of drug-resistant infections. Hospitalized patients are one of the main reservoirs of resistant microorganisms. Patients who are carriers of resistant microorganisms can act as a source of infection for others.

WHO/Simon Lim

Weak surveillance systems contribute to the spread of drug resistance

While surveillance for the emergence of drug resistant TB and HIV infection is improving, currently there are few well-established networks that regularly collect and report relevant data on drug resistance. Some countries lack laboratory facilities that can accurately identify resistant microorganisms. This impairs the ability to detect emergence of resistance and take prompt actions.

WHO/H. Ruiz

The pipeline for new tools to combat drug resistance is almost dry

Existing antibiotics and anti-parasitic drugs, and, to a lesser extent, antiviral drugs, are losing their effect. At the same time there is insufficient investment in developing new antimicrobials. Similarly, there is insufficient new research into new diagnostics to detect resistant microorganisms; and new vaccines for preventing and controlling infections. If this trend continues, the arsenal of tools to combat resistant microorganism will soon be depleted.

WHO/P. Albouy

WHO calls on stakeholders to combat drug resistance

The threat from drug resistance is increasing. There is a need for urgent action; everyone must play a part. At the Sixty-eighth World Health Assembly in May 2015, Member States endorsed a global action plan to tackle antimicrobial resistance. The goal of the draft global action plan is to ensure, for as long as possible, continuity of successful treatment and prevention of infectious diseases with effective and safe medicines that are quality-assured, used in a responsible way, and accessible to all who need them. Countries have been encouraged to develop national action plans to help achieve the global action plan objectives. So far 79 countries have national action plans, and a further 49 countries are in the process of developing a plan.