FIG. 1.

Clinical and virological profiles of ponies experimentally infected with EIAV_PV. Ponies were experimentally infected with 10³ TCID₅₀ of the biological clone EIAV_PV. Rectal temperature (——) and platelet count (⋯) were followed daily for up to 900 days (x-axis) after inoculation. Quantitation of the virus load () was performed on viral RNA extracted from plasma at periodic time points during the fever episodes and asymptomatic stages. The symbol ✯ indicates a virus load below 100 copies. Febrile episodes I to VI were defined by a rectal temperature above 39°C in conjunction with a reduction in the number of platelets below 100,000/μl of whole blood and other clinical symptoms of EIA. M, virus isolation from macrophages. Data are adapted in part from reference 11.