There are four known cockroach species that reside in Washington state.
- The German cockroach
- The American cockroach
- The brown-banded cockroach
- The oriental cockroach
The American cockroach is the largest cockroach found, and can survive through freezing temperatures, live up to two to three months without food, and a month without water. They are mostly found in restaurants, grocery stores, and commercial areas where food is prepared or stored. They live in moist areas, such as bathtubs, clothes hampers, basements and sewers, etc.
The German cockroach is the most common cockroach in the Pacific Northwest. They live in homes and apartments and wherever food is stored, prepared or served.
Brown-banded cockroaches are very active and the adults jump when disturbed. They are more likely to be found in homes. They prefer warm places such as the closet, near the ceiling, and behind kitchen appliances. They are more difficult to control because of how and where they hide.
Oriental cockroaches live mostly outdoors and dwell in cool moist environments. During very cold climate spells, they can invade structures through sewers, drainpipes, and foundation cracks.
A 2005 US national study on factors that affect asthma in inner-city children shows that cockroach allergens appear to worsen asthma symptoms more than other known triggers. This study, funded by the National Institute of Environmental Health Sciences (NIEHS) and the US National Institute of Allergy and Infectious Diseases (NIAID), is the first large-scale study to rank asthma triggers according to severity.
Additionally, a 2005 research study, sponsored by the National Pest Management Association (NPMA), shows a disparity in homeowner knowledge about this link. Only 10% of homeowners nationwide feel that cockroaches are a threat to their family's health.