Académie royale de Médecine de Belgique

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Vidéo et résumé de George Griffin


INFECTION AND ANTIMICROBIAL RESISTANCE : HEALTH IMPACT  

par George E. GRIFFIN (St George’s, University of London), membre étranger. 

President Federation of European Academies of Medicine (FEAM).

Resistance of microorganisms to antimicrobial agents is an ascendingly serious global problem and has been designated by the World Health Organisation as one of the major health problems facing both developed and developing countries.

There is no doubt that overuse and ease of access to antimicrobial agents has fuelled this serious situation. Whilst efforts to restrict antibiotics use, the global situation remains alive.

Resistance to penicillin was described soon after its discovery and it is now well recognised that resistance emerges quickly when new antibiotics are introduced.

Bacteria are self-replicating machines which reproduce rapidly in response to environmental conditions. In addition, they can transmit DNA encoding resistance factors on plasmids by conjugation thus enabling new generations of resistant organisms. This transfer is achieved through an appendage, the pilus, which is a tube allowing plasmid DNA to move between bacteria. When such genetic resistance is conferred exposure of microorganisms to an antibiotic to which it was previously sensitive is lost and the resistant clones reproduce with speed. Currently there are serious AMR complications arising for important human pathogens particularly gram-negative organisms and mycobacterium tuberculosis.

The range of antimicrobials needed to treat these organisms is becoming very small and patients and communities are at high risk, particularly for multidrug resistant tuberculosis. Mechanisms of AMR are actively under investigation in order to provide ways to overcome such resistance. The discovery of new antibiotics is an active area of research and currently principally depends upon isolating agents from natural sources. However, the commercial return from such drug development is potentially small and is a deterrent to pharmaceutical companies. In addition, the judicious and controlled use of antibiotics is major target to reduce AMR however the sociological aspect of use beliefs in the power of antibiotics make this difficult. New rapid diagnostic techniques provide a major step forward in helping clinicians decisions in prescribing antibiotics. For example, PCR technology can identify drug resistant genotypes of bacteria within hours and distinguish between viral and bacterial infections. In addition, such rapid diagnostic technology is a huge advance in the management of tuberculosis.

The discovery and clinical use of antibiotics has been a major medical advance, second only to vaccination. However, the world is now facing a huge problem of AMR which is making some bacterial infection difficult and likely in the future impossible to treat.

References :

1) The cost of antimicrobial resistance. Ursula Hofer. Nature Reviews Microbiology vol. 17, page3, 2019.

2) Attributable deaths and disability-adjusted life-years caused by infections with antibiotic-resistant bacteria in the EU and the European Economic Area in 2015: a population-level modelling analysis. Alessandro Cassini et al. The Lancet – Infectious Diseases, Vol. 19, issue 1, P56-66, 2019.

3) Prediction of Susceptibility to First-Line Tuberculosis Drugs by DNA Sequencing. CRyPTIC Consortium and the 100,000 Genomes Project, N. Engl. J. Med 2018; 379:1403-1415, 2018.