Herd Teat Bulk Milk Cheese Humana A 9 2 1 Nose5 Hands5 B 21 3 3 Nose5 Hands5 C 23 3 3 Nose4 Hands5 D 20 1 2 Nose5 Hands5

Table 2: Origin and number of samples taken on study farms. aSamples taken from the farmer, the manufacturer and the sampler.