Translations:Advanced Field Epi:Manual 1 - Disease Investigation/16/en

Budi watches the 45 cows over the next 7 days. He calls and says that 8 more cows have become sick. The animals at risk are those that are disease free at the start of a period. At the start of the 7 day period there are 45 cows but 5 have already been diagnosed with the disease so this leaves 40 that were disease free at the start of the7 day window.