English Abstract The European Antimicrobial Resistance Surveillance
System (EARSS) is an international initiative funded by the Director General
for Health and Consumer Protection (DG SANCO) of the European Commission and
the Dutch Ministry of Health, Welfare and Sports. It maintains a
comprehensive surveillance and information system that links national
networks by providing comparable and validated data on the prevalence and
spread of major invasive bacteria with clinically and epidemiologically
relevant antimicrobial resistance in Europe.
EARSS collects routinely generated antimicrobial susceptibility (AST) data,
provides spatial trend analyses and makes timely feedback available via an
interactive website at www.rivm.nl/earss. Routine data for major indicator
pathogens (Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus
faecalis, Enterococcus faecium, Escherichia coli, Klebsiella pneumonia and
Pseudomonas aeruginosa) are regularly submitted by over 900 laboratories
serving around 1400 hospitals in 32 European countries. By the end of 2005
two new countries joined the EARSS initiative, Lithuania and Turkey. Based
on a previous laboratory/hospital questionnaire, the overall hospital
catchment population of the EARSS network is estimated to include over 100
million inhabitants in the European region, with national coverage rates
that ranged between 20-100% for individual countries. In 2005, information
on the laboratory demands for external quality assessment (EQA) was
collected by questionnaire. Several countries do not have formal agreements
on national or international quality assessment schemes in place. Among the
international providers of EQA the British UK-NEQAS scheme was most
frequently named by countries. Alternatively, different national schemes
are in place, either alone or in combination with one of the international
programs. Importantly, the majority of laboratories that participate in
EARSS utilise some type of EQA, demonstrating their commitment to diagnostic
accuracy.
In Europe the proportion of antibiotic resistant S. pneumoniae keeps
changing with decreasing penicillin-resistance in some highly endemic
countries and with continuous loss of susceptibility against penicillin and
erythromycin in others. The main resistance phenotypes in pneumococci are
confined to few serogroups, all of which are included in the currently
promoted conjugate vaccines. This suggests that vaccination, especially in
young children, may represent an effective additional means of controlling
antibiotic resistance in pneumococcal disease in Europe. The increase of
MRSA is consistent throughout Europe and includes countries with high,
medium and low baseline MRSA endemicity. At the same time it appears that
the MRSA pandemic is not an irreversible secular trend as two European
countries (Slovenia and France) succeeded in constantly reducing the
proportion of MRSA among S. aureus blood stream infections over the past
five or six years.
The speed with which fluoroquinolones loose their activity against E. coli
is next to no other compound pathogen combination in the EARSS database.
Combined resistance is a frequent occurrence, with co-resistance to three
antimicrobial classes including third generation cephalosporins already
among the four most common resistance patterns encountered in invasive E.
coli in Europe, and undeniably these resistance traits are on the increase
as well. In K. pneumoniae a high prevalence of resistant strains to third
generation cephalosporins, fluoroquinolones and aminoglycosides becomes
evident in Eastern and Southeastern Europe. Combined resistance is the
dominant threat imposed by invasive P. aeruginosa. Our data suggest that
the same geographical gradient exists for all gramnegative pathogens and
shows that lower resistance prevails in the Northwest with increasing
resistance towards the Southeast of Europe. It appears that the overall
threat imposed on European communities by the increasing loss of
antimicrobial effectiveness continues unabated with the same speed as has
been previously described by our network. This is shown most convincingly
among the pathogens that are frequently transmitted in health care settings
(MRSA and VRE) and for antimicrobial compounds that are available for oral
administration and hence preferred in ambulatory care (aminopenicillins,
macrolides, and fluoroquinolones). The growing availability of third-line
antimicrobial drugs as oral formulations is in this context a matter of
concern and underscores the need of locally or nationally advised
prescribing practices for both ambulatory and hospital-based
care.