Exploring Campylobacter seasonality across Europe (2008-2016) using The European Surveillance System TESSy

Infections with Campylobacter are the most commonly reported food-borne illnesses in the EU. The most striking epidemiological characteristic of this illness is the seasonal peak observed in many countries during early/mid-summer. Ten years ago a couple of papers examined Campylobacter seasonality across Europe and associations with weather. Subsequently several European countries have introduced measures against food-borne disease. Here we revisit Campylobacter seasonality and associations with weather across 18 European countries using recent data (2008-2016). Using Ward’s Minimum Variance clustering we find six groups of countries, each having similar seasonal Campylobacter patterns. Nordic countries were found to have a pronounced seasonal peak in mid to late summer (Weeks 29-32), while most other European countries have a less pronounced peak earlier in the year (week 26). The UK, Ireland, Hungary and Slovakia have a slightly earlier peak (week 24). A comparison with previous papers indicates that the strength and timing of the Campylobacter peak has remained similar over 10 years. A two-stage multivariate meta-analysis methodology indicated that Campylobacter cases were positively associated with temperature and to a lesser degree rainfall. We highlight the advantages of the European Surveillance System (TESSy) in providing standardised datasets on health data across Europe from one central repository, but note its reliance upon within country reporting infrastructure.