Poultry Culling and Campylobacteriosis Reduction among Humans, the Netherlands

Ingrid H.M. Friesema

, Arie H. Havelaar, Paul P. Westra, Jaap A. Wagenaar, and Wilfrid van Pelt

Author affiliations: National Institute of Public Health and the Environment (RIVM), Bilthoven, the Netherlands (I.H.M. Friesema, A.H. Havelaar, W. van Pelt); Utrecht University, Utrecht, the Netherlands (A.H. Havelaar, J.A. Wagenaar); Product Boards for Livestock, Meat and Eggs, Zoetermeer, the Netherlands (P.P. Westra); Central Veterinary Institute, Lelystad, the Netherlands (J.A. Wagenaar); World Health Organization Collaborating Centre for Reference and Research on Campylobacter, Utrecht (J.A. Wagenaar); World Organisation for Animal Health Reference Laboratory for Campylobacteriosis, Lelystad (J.A. Wagenaar)

Abstract

In the Netherlands in 2003, an outbreak of avian influenza in poultry resulted in extensive culling, especially of layer hens. Concurrently, human campylobacteriosis cases decreased, particularly in the culling area. These observations raise the hypothesis that Campylobacter spp. dissemination from poultry farms or slaughterhouses might contribute to human campylobacteriosis.

In the Netherlands during March–May 2003, an outbreak of avian influenza (H7N7) virus among poultry led to the culling of >30 million birds (1). The outbreak, and thus the culling, was confined to a relatively small area of 50 × 30 km in the center of the country (2). A few years after the avian influenza outbreak, it became apparent that the incidence of campylobacteriosis among humans had decreased during 2003 and that the extent of this decrease varied by region. Because the avian influenza outbreak strongly affected the poultry industry in 2003, a link was suspected.