Most of the antimicrobial drug resistance (AMDR) problems are currently associated with bacteria, which are often virulent, multi-drug resistant strains of the pathogenic species. The AMDR portfolio of infectious diseases research at DG RTD addresses both the biology and medical implications of this phenomenon. Because AMDR problem permeates multiple overlapping areas of research and practice, the projects often deal with the groups of pathogens or diseases rather than individual entities.
Research on epidemiology, complemented by bacterial genomics, identifies AMDR organisms and determines their prevalence and spread with the aim to develop countermeasures to these threats. Control and prevention modalities against AMDR include guidelines for evidence-based clinical practice and patient management, which are largely based on the clinical research on drug-resistance among community-acquired and hospital (nosocomial) infections. In long-term perspective, the success of many modern diagnostic and treatment modalities, including advanced surgery and chemotherapy, depends upon effective solutions to the AMDR problem.
One focus of AMDR research, comprising microbial and human genomics and clinical observational and intervention studies, is the diagnosis and management of community-acquired upper and lower respiratory tract infections. These infections, which include pharyngitis, sinusitis, otitis media, bronchitis, and pneumonia, are leading reasons for seeking medical care. The promiscuous use of antibiotics for their treatment accounts for the greatest part of the community burden of antibiotic use and contributes dramatically to AMDR among common pathogens, such as Streptococcus pneumoniae and Haemophilus influenzae. The understanding of the epidemiological, medical and health economics correlates of diverse antibiotic prescription practices is instrumental for articulating prudent management strategies of the patients. Antibiotic audit, which is the analysis of the appropriateness of individual antibiotic prescription, further contributes to the rationale for interventions countering AMDR.
Hospitalised patients, especially those in intensive care units and surgery, are exposed to significant risk of infection with multi-drug resistant pathogens. DG RTD-funded studies have in the past identified the following AMDR organisms of concern to the hospitals in Europe:
In addition, the European health systems are increasingly challenged by the emerging hypervirulent and antibiotic-resistant strains of Clostridium difficile. This pathogen causes pseudomembraneous colitis in the patients undergoing broad-spectrum antibiotic therapy for other diseases.
The basic-molecular and translational research on nosocomial AMDR infections focuses on genetic determinants and pathogenetic mechanisms of host-pathogen interactions. Studies addressing the emergence, dynamics and transmission of multi-drug resistant pathogens in hospitals are expected to guide optimization of patient care through prevention, improved etiological diagnostics and rational use of antibiotics. Point-of-care diagnostic tests are being developed for MRSA, Clostridium difficile and vancomycin-resistant Enterococcus species.
Inasmuch as the need for new drugs is particularly urgent for severe hospital infections caused by Gram-negative bacteria, a special effort has recently been made to invigorate this research field. Several projects seek antibacterial compounds acting against previously validated or novel targets of these pathogens, using medically important model organisms such as Pseudomonas aeruginosa and Escherichia coli.