FIG. 4.
Clinical and virologic profiles of control naive horses. Four horses (A to D, respectively) were subjected to challenge with virulent EIAVPV by using the LDME protocol (see Materials and Methods). Rectal temperature (solid line, right y axis) and platelet counts (dotted line, first left y axis) were monitored daily for up to 300 days (x axis) postchallenge. Quantification of the virus load (♦, second left y axis) was performed on viral RNA extracted from plasma at periodic time points prior to and after virulent virus challenge by using the LDME protocol (arrows). Febrile episodes were defined by a rectal temperature of >39°C in conjunction with a reduction in platelets (<100,000/μl of whole blood) and other clinical symptoms of EIA.