Experimental infection of young turkeys with eastern equine encephalitis virus and highlands J virus

Depression, somnolence, and increased mortality were observed in 2-week-old turkeys inoculated intramuscularly with either eastern equine encephalitis (EEE) virus or Highlands J (HJ) virus. Mortality rates in EEE virus- and HJ virus-inoculated turkeys were 7/30 (23%) and 9/30 (27%), respectively; no sham-inoculated controls died. Both EEE virus- and HJ virus-inoculated turkeys developed viremia that lasted 2 days; peak mean titers were 5.5 and 3.2 log10 plaque-forming units per ml of blood, respectively. Pathologic changes in both EEE virus- and HJ virus-inoculated turkeys consisted primarily of multifocal necrosis in the heart, kidney, and pancreas, and lymphoid necrosis and depletion in the thymus, spleen, and bursa of Fabricius. The findings indicate that EEE virus and HJ virus are pathogenic for young turkeys.