The West Nile Virus keeps expanding. The standing water left from Tropical Storm Edouard now presents an ideal breeding place for mosquitoes. Two more horses in Eastern Washington have been diagnosed with West Nile virus. Mosquitoes infected with the virus have been detected in nine counties statewide this year.

Officials from Los Angeles, Orange, Riverside, San Bernardino and San Diego counties gathered Tuesday in Garden Grove to announce the assault against West Nile and the mosquitoes that transmit it.

Humans and animals contract West Nile virus from bites of infected female mosquitoes, which contract it by feeding on birds that have the virus in their blood.

The Central District Health Department (CDHD) has been working along with the Elmore County Interim Mosquito Abatement District to provide surveillance of mosquito populations.

Central District Health Department officials recommend applying insect repellent containing DEET on exposed skin and clothing as well as avoiding exposure at dusk and dawn. Elderly people were asked to pay more attention, as they are more likely to develop severe complications, as their immune system is weakened.

Conditions for mosquitoes that carry the West Nile virus are nearly ideal this year thanks to a number of factors, including a lack of severe cold weather last winter, large numbers of heavy rainstorms in the spring and early summer, and the region's dense population growth, East Middlesex Mosquito Control Project superintendent David Henley said last week.

Local health officials are warning that August could be the worst month for West Nile virus in years. Recent weather has created ideal conditions for the mosquitoes that spread the disease.