Two groups of mosquitoes trapped near Wilfred Avenue in Rohnert Park have tested positive for West Nile virus, whose activity has occured earlier this year than last. Spokesperson for the Marin/Sonoma Mosquito and Vector Control District Nizza Sequeira said that dairy ponds are favored hatching grounds for the carrier mosquitos. District technicians are checking known mosquito sources and searching for anything else that may be producing mosquitoes, and adult mosquito surveillance traps are monitoring the abundance of mosquitoes, Ms. Sequeira said. Ron Chapman of the California Department of Health suggest that in order to lower chances of infection, which results from bites from mosquitoes that have fed on infected birds, residents should remember the “Three D’s”: Defend—Use insect repellent with DEET, picaridin, oil of lemon eucalyptus or IR3535; Dawn and dusk—Mosquitos that carry West Nile virus bite in the early morning and evening; and Drain—Mosquitoes lay their eggs on standing water, so eliminate infestation by removing standing water from buckets, old tires, pet bowls and any other places.