Fig. 1.

Time course of the Q fever epidemics in The Netherlands with the number of notified cases per week (gray bars). Red bars indicate the week in which an abortion wave was registered at one (or two: ‘2’) farms. The non-systematic bulk tank milk (BTM) tests were performed in the autumn of 2008; the mandatory and systematic BTM tests were performed from September 2009. Mandatory and systematic vaccination and culling started at the end of December 2009. The geographic map of The Netherlands shows the location of all large dairy goat farms with abortion waves (♢), all other positive (•) and negative (○) farms.