PulseNet Europe is the molecular surveillance network for food-borne infections in Europe. It is an internationally unique network that - in addition to public health laboratories - has institutions from the veterinary and food sector as equal participants.
PN Europe was funded from September 2004 until November 2006 by the FP network of excellence Med-Vet-Net, a virtual European Zoonosis Centre (www.medvetnet.org(external link)). The main aim was to establish real-time linked surveillance database system to detect infection clusters and investigate outbreaks of Salmonella, verocytotoxigenic E. coli (VTEC) and Listeria monocytogenes in Europe.
The developed web-based molecular surveillance system includes customised BioNumerics software with PN Europe scripts and is fully compatible with other PN networks. The DNA-fingerprinting method used is pulsed-field gel electrophoresis (PFGE) which has been standardised by PN USA.
A PN Europe communication system called PNE forum(external link), is used to exchange of active information and alert PN Europe partners when an international cluster is detected at the central database or partner has detected a cluster at the national level. The PFGE image of the profiles can also be attached to the alert email.
The quality of the PFGE profiles, which will be uploaded to the central database, and uniform naming are very important. Therefore, six PN Europe curators have been chosen. They take care of the central database, perform the naming and confirmation of the PFGE profiles submitted by partners and perform central cluster detection of all pathogens at regular intervals and alerts PN Europe partners of detected clusters through communication system.
A European Quality Assurance System (EQAS) system was created and certification of partners has been started to ensure the comparability of the data uploaded from different laboratories. The certified partners, who have signed the memorandum of understanding, which defines the rules for exchange of molecular typing data, have been given passwords to the central database.
A memorandum of understanding (MoU) between PN Europe partners has been signed by all partners to define the rules for collaboration allowing exchange of information and molecular typing data between PN Europe partners. A MoU with PN USA has also been drafted.
The PNE participants represent public health, veterinary and food laboratories from 65 Institutes from 31 countries (Fig. 1). These partners have direct access to the PN Europe central databases when they have received certification and have signed the memorandum of understanding between PN Europe partners.
The direct access to specific databases for Salmonella, verocytoxin-producing Escherichia coli and Listeria monocytogenes will ensure a uniform naming of PFGE-subtypes in all participating countries, provide portable data and make it easy for partners to check and compare their own data to the data that are stored in the database. Furthermore, the direct access to comparable typing data for isolates from human infections as well as food and animals will significantly improve the surveillance and trace-back of food-borne infections at the national, European and international level. Also, international clusters of food-borne infections that have too few cases in each country to be detected by the national surveillance systems will be detected through the central PN Europe surveillance system.
PN Europe is currently in the process of being taken over by the European Centre for Disease Prevention and Control (ECDC) in Stockholm, Sweden. Ongoing activities and the central databases will probably be transferred to ECDC to Stockholm during 2008. Therefore, all administrative work has been minimised in this period without funding. However, partners have been encouraged to use the PNE forum for discussion and questions as well as in outbreak situations by sending out alerts including an attached TIFF file of an outbreak profile when clusters have been detected at the national level.
For further information please contact:
Eva Møller Nielsen, Statens Serum Institut, Denmark.
Figure 1 Countries and number of institutes involved in PulseNet Europe.