Fig. 4.

Time series of OD ratios for 11 camels identified as having serological indication of probable infection from a single closed herd in Matrouh governorate, Egypt, from December 2019 to March 2020 with sampling carried out 10 times at 10-day intervals. Camel 10 was negative on the first sampling round, seroconverted in the second and remained seropositive thereafter. Camel 8 seroconverted from negative on sampling round 7 to positive on sampling round 8, after having tested positive in the first six sampling rounds. The remaining camels experienced doubling of their OD ratio in consecutive sampling rounds. The red dashed line represents the threshold for positive test result