The latest update posted by APHIS shows 193 total cases of EEE and 64 cases of WNV through Sept. 2. During all of 2008, there were 185 EEE cases and 178 WNV cases.
Both mosquito-borne diseases are preventable by vaccination, but there is concern in the veterinary community that the down economy may have led some horse owners to neglect vaccinations or under-vaccinate their horses.
The reported cases of both diseases have occurred in 22 states.
Most EEE cases so far this year are in Florida, which reported 64 as of Sept. 2, most of them in the state's north-central and northeast coastal counties. Georgia is second with 36 cases and Louisiana third with 19.
Most WNV cases in recent years have been in western states, reflecting the vector's steady movement from east to west. Washington reported 23 WNV cases by Sept. 2, followed by Montana with eight, Idaho with five and California with four cases.
No cases of the Western variety of equine encephalitis are reported so far this year.