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Multnomah County, which is responsible for public health, has a different view of pests than exterminators. The county regards them as vectors, or organisms that transmit disease.
The county's six-person vector control team mainly monitors county mosquito populations and helps residents address rodent problems.
"Is it hazardous?" says Chris Wirth, manager of Multnomah County Vector Control & Code Enforcement. "Well, they're working out in the field, they're in swamps, there's beavers. I don't know—it's all relative."
Wirth says there are no environmental or weather conditions to indicate this season will yield more or fewer vectors than normal. Local residents will encounter cockroaches, which mainly pose a threat when they shed their asthma-triggering exoskeletons, and ticks, which can spread Lyme disease and a malady called "relapsing fever" to their victims.
Rats and mice can carry hantavirus, which can cause a deadly disease that one can contract by inhaling dust contaminated with the feces or urine of an infected rodent.
To reduce your risk of infection from hantavirus, Wirth cautions against entering or cleaning long-vacant buildings such as garages, hunting shacks and storage sheds without a dust mask. He also recommends trying to get rid of rodents by limiting their shelter, food and water sources before resorting to traps or poison.
Wirth says county officials will intensify their monitoring of mosquito populations this year because of the Zika virus, an infectious agent causing birth defects in Brazil and other countries. Zika-carrying species such Asian tiger mosquitoes and yellow fever mosquitoes have been detected in California, so vector control employees will be watching closely to see whether the pests can travel here and survive in Oregon's cooler climate.
"It's important to monitor for northerly progression," Wirth says. "With world trade, there's always the risk of introducing a new species into an area.
Willamette Week