Campylobacteriosis in returning travellers and potential secondary transmission of exotic strains

Abstract

Multilocus sequence types (STs) were determined for 232 and 737 Campylobacter jejuni/coli isolates from Dutch travellers and domestically acquired cases, respectively. Putative risk factors for travel-related campylobacteriosis, and for domestically acquired campylobacteriosis caused by exotic STs (putatively carried by returning travellers), were investigated. Travelling to Asia, Africa, Latin America and the Caribbean, and Southern Europe significantly increased the risk of acquiring campylobacteriosis compared to travelling within Western Europe. Besides eating chicken, using antacids, and having chronic enteropathies, we identified eating vegetable salad outside Europe, drinking bottled water in high-risk destinations, and handling/eating undercooked pork as possible risk factors for travel-related campylobacteriosis. Factors associated with domestically acquired campylobacteriosis caused by exotic STs involved predominantly person-to-person contacts around popular holiday periods. We concluded that putative determinants of travel-related campylobacteriosis differ from those of domestically acquired infections and that returning travellers may carry several exotic strains that might subsequently spread to domestic populations even through limited person-to-person transmission.

Fig. 1.

Sequence types identified in Campylobacter jejuni/coli isolates from (a) 737 non-travellers (infections acquired in The Netherlands) and (b) 232 travellers returning to The Netherlands. Category ‘others’ includes sequence types that occurred less than five times (non-travellers) and less than twice (travellers).

Fig. 2.

Clonal complexes identified in Campylobacter jejuni/coli isolates from (a) 737 non-travellers (infections acquired in The Netherlands) and (b) 232 travellers returning to The Netherlands. Category ‘others’ includes clonal complexes that occurred less than twice (non-travellers) and less than once (travellers).