BYRON PONDS, Yakima County — The traps dangle from shepherd's hooks or tree branches and Kylie Morgan keeps an eye out for them as she drives her truck carefully over the rough, pitted back roads in south central Washington. She stops at each trap site and inspects her loot, gently tapping the catch bags with her fingertips to nudge a black swarm of mosquitoes off the cloth sides. She pulls the draw string taught. Everything goes in a cooler in the truck bed until she returns to the lab in Richland where the insects will be tested for deadly pathogens, like West Nile virus. So far this year th...