Eurosurveillance - Volume 9, Issue 1, 01 January 2004

In this issue, Witte and colleagues report on the emergence, since 2002, of cases in Germany of infection with community-acquired methicillin-resistant Staphylococcus aureus (c-MRSA) producing the Panton-Valentine leukocidin. This report adds evidence to the rapid geographical dissemination of this emerging, hyper-virulent variant of an 'old pathogen' across Europe. First reported in the early 1990s among aboriginal populations in Western Australia, outbreaks of c-MRSA infections have more recently been described in population groups such as prison inmates, injecting drug users, sports teams and schoolchildren, in the United States and Europe. Current evidence from molecular studies points to the spread in each continent of a limited number of PVL-producing MRSA clones that are genetically distinct from epidemic nosocomial strains. This represents a public health threat, because these strains are associated with severe soft tissue and pulmonary infection and the outcome of MRSA infection is worse than with infection caused by beta-lactam susceptible S. aureus, especially if inappropriately treated with beta-lactams that are usually prescribed for these infections. We must, therefore, upgrade the diagnostic work-up for this kind of infection in the outpatient setting and adapt empirical therapy accordingly. Moreover, surveillance should be intensified to monitor the incidence of MRSA and detect and control outbreaks in the community. In this respect, the report by Witte et al underscores the important early warning role that reference laboratories can play by using high resolution molecular markers based on routine typing and susceptibility data.

Analysis of community-acquired methicillin-resistant Staphylococcus aureus (c-MRSA) from Germany producing the Panton-Valentine leukocidin revealed a unique SmaI-macrorestriction pattern, different from epidemic nosocomial strains. This molecular pattern corresponds to those shown in c-MRSA strains from other countries in the European Union. All isolates exhibited resistance to fusidic acid, which is coded by the far-1 gene. From data on geographical dissemination and time of occurrence, this strain appears to have emerged in Germany in the second half of 2002, and so an already wider dissemination is likely. The emergence of MRSA with resistance to fusidic acid is a first sign of the emergence of a PVL-positive MRSA clone.

In 2001 the European Commission presented a 'Community strategy against Antimicrobial Resistance'. In previous years, the problem was addressed through an increasing number of isolated measures, but in this strategy the Commission outlined a comprehensive European Community approach across all sectors. The strategy consists of fifteen actions in four key areas: surveillance, prevention, research and product development, and international cooperation. An important part of this strategy is the 'Council Recommendation on the prudent use of antimicrobial agents in human medicine'. The Recommendation provides a detailed set of public health actions to contain antimicrobial resistance. This paper presents the eleven points of action of the strategy that are directly related to human medicine, and discusses related European Community activities. Under the new public health programme as well as under the research programme of the European Union, antimicrobial resistance is a key priority.

The European Influenza Surveillance Scheme (EISS) is based on an integrated clinical and virological surveillance model. To assess the comparability of virological data, a questionnaire was sent to participants in June 2002 enquiring about specimen collection, laboratory diagnosis of influenza and tests for other respiratory infections. The results showed differences, but also uniformity in virological data collection methods. Similarities were reported for the specimen collection procedures; the type of swab and the transport conditions were comparable. The diagnostic methods were diverse; differences were seen in the (sub)typing methods, with PCR used most often in western countries. The findings will be helpful for the interpretation of virological data collected by sentinel physicians and for the creation of a Community Network of Reference Laboratories for Human Influenza in Europe. Important objectives of the Community Network include the harmonisation of virological methods and the application of quality assurance assessments for the national reference laboratories.