Two Denver residents are the first Coloradans to die of the mosquito-borne West Nile virus this season.

The Colorado Department of Public Health and Environment announced Friday that the dead are a 63-year-old who became ill in mid-July and died on Aug. 2, and a 77-year-old who became ill in late July and died on Aug. 4.

The first died from complications of encephalitis, the second from meningoencephalitis - both brought on by West Nile.

State health officials urged Coloradans to use DEET and take other precautions, especially for the next three weeks when the West Nile-carrying mosquitoes are still active.

"These tragic events underscore how serious West Nile virus infections can be and why it is important to take precautions to avoid mosquito bites," John Pape, an epidemiologist with CDPHE, said.

He said rural areas usually get hit harder. But the two Denver cases emphasize the fact that no areas of eastern Colorado are free of risk.

Seventy-two cases of West Nile virus have been reported to the state so far this year, Pape said. "The number will continue to rise" as new cases are reported daily.

Last year, seven Coloradans died of West Nile, with the first death occurring later - on Aug. 25, Pape noted.

Mosquito numbers are up, and this could be the worst year since 2003, when Colorado led the nation in deaths with 63 deaths and 2,947 cases.

Pape urged people to follow the "Four Ds":

? Dawn/dusk - Use protection or avoid being outside when mosquitoes are most active.

? Dress - Wear loose fitting, lightweight long sleeves and pants when outside.

? DEET - Use an insect repellent with DEET or another repellent approved by the Centers for Disease Control and Prevention.

? Drain - Get rid of standing water in your backyard and neighborhood. Drain any standing water in old tires, flowerpots and clogged rain gutters. These are mosquito-breeding sites.

For more information, call 1-877-462-2911 or go to www.fightthebitecolorado.com .

scanlonb@RockyMountainNews.com or 303-442-8729