Health District Staff Will Provide Consultation For The General Public Regarding Pests. Additional Information Can Be Found On The Washington State Department Of Health Pests Webpage.


Rodents such as mice and rats can carry harmful diseases. Diseases from rodents can spread to people through bite wounds, eating contaminated food or water, or breathing in germs from rodent urine or droppings that are stirred into the air.  Among many others, some of the communicable diseases that rodents can transmit include Hanta virus, Salmonella, and Rat-Bite Fever.

You can help to prevent rodent infestations by removing their sources of food, water, and shelter by:

  • Storing pet and people food, bird and lawn/garden seed, and animal feed indoors in containers with tight fitting lids.
  • Cleaning up food waste and using thick plastic or metal garbage cans with tight lids.
  • Keeping the area around your home and outbuildings clear of junk and debris. Clean up wood piles and junk that can serve as habitat or hide burrows.
  • Trimming vegetation and don’t allow plants to grow up alongside your house.
  • Cleaning up fallen fruits or nuts from trees and animal waste.
  • Routinely mixing compost piles to encourage rapid decomposition.
  • Storing firewood, lumber, or hay at least 12 inches off the ground and away from your home.
  • Trapping and poisoning rats are effective control measures. Read instructions carefully to avoid accidents.
  • Seek professional pest management if you find rat burrows on your property or need assistance.

Additional information on how to seal up your home, trap rodents and cleaning up after rodents can be found the Washington State Department of Health Rodents webpage.


Not only a nuisance, mosquitoes can pose a serious health threat to people. Disease can be spread to people through the bite of an infected mosquito. Over 40 different mosquito species can be found in Washington, and many are vectors for diseases, such as West Nile virus. Zika virus disease can also be spread through the bite of an infected mosquito, however, Washington State does not that the type of mosquitoes (Aedes aeqypti and Aedes albopictus) that carry Zika virus.

Bed Bugs

Bed bugs are not known to transmit human diseases, but they can cause skin welts, local inflammation, and contribute to insomnia. Bed bugs have been found in homes, apartments, rental units, and even hotels throughout Washington with increasing frequency. The WSU Extension fact sheet on Bed Bugs provides more information on recognizing bed bugs, signs of bed bug infestation, and pest management approaches.


Going hiking? Prepare for ticks as the warm weather hits! Here are some Hiking Tips from the CDC.

Biting Flies

Black flies are small, biting flies that are a nuisance to people and animals living, working, or playing near rivers and streams. Black flies are sensitive to weather conditions. They are most active on cloudy, humid days with low wind. These flies are typically dark in color and some species are also referred to as ‘punkies’ or ‘no-see-um’s’. On people, they crawl into sleeves, under neck bands, around boot tops and other vulnerable places, especially favoring the head just beneath the rim of a hat. Bites can cause swelling and numb soreness for many days. The painfully itchy bite of the black fly is created when it cuts a hole in the skin to suck blood from animals and people. The flies attack around the eyes, ears, scalp and occasionally on the arms and exposed legs. The pain and swelling of the bite are due to the body’s allergic response to the fly’s saliva that they inject when feeding. Fortunately, black flies do not transmit any diseases to humans in Washington state, but can cause discomfort and irritation. Again, although black flies are a nuisance, they do not transmit disease, and therefore are not considered a public health risk.

Take these simple steps for biting flies:

  • Avoid areas where black flies are active during the day, especially at dusk and dawn.
  • Wear light-colored long pants and long sleeves, especially whites and tans. Also wear a light colored hat.
  • Consider using insect repellent to reduce your chance of being bitten.
  • If you are bitten, clean the bite and apply topical products to reduce itching. Avoid scratching to reduce chances of infection.

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