BALTIMORE (WJZ) — Baltimore tops this year’s list from the Orkin extermination company of cities with the most beg bug infestations.

In the six years Orkin has released the bed bug city rankings, this is the first time Baltimore has made the top five, moving up nine spots since last year. Chicago held the top ranking for four straight years.

Four other metro regions — Las Vegas, Portland, Salt Lake City and Greensboro-High Point-Winston Salem — made the list for the first time this year.

The list is based on treatment data from the metro areas where Orkin performed the most bed bug treatments from December 1, 2015 – November 30, 2016.

The ranking, seen below, includes both residential and commercial treatments. The numbers next to the cities indicate how many spots they have moved up or down on the list since last year.

Baltimore (+9) Washington, D.C. (+1) Chicago (-2) New York Columbus, Ohio Los Angeles (-4) Detroit Cincinnati Philadelphia (-3) San Francisco-Oakland-San Jose (+4) Richmond-Petersburg, Va. (-2) Raleigh-Durham, N.C. (-1) Cleveland-Akron-Canton, Ohio (-1) Indianapolis (+1) Dallas-Ft. Worth (-2) Atlanta (+3) Houston Buffalo, N.Y. (+2) Charlotte, N.C. (-3) Norfolk-Portsmouth-Newport News, Va. (+10) Knoxville, Tenn. (+3) Denver (-4) Nashville, Tenn. (-1) Pittsburgh (+5) Greenville-Spartanburg, S.C.-Asheville, N.C. (-4) Phoenix (-3) Grand Rapids-Kalamazoo-Battle Creek, Mich. (+5) Boston (-3) Milwaukee (-3) Champaign-Springfield-Decatur, Ill. (+12) Hartford-New Haven, Conn. (+3) Dayton, Ohio (-4) Omaha, Neb. (+3) Seattle-Tacoma (-6) Tampa-St. Petersburg, Fla. (-4) Charleston-Huntington, W.Va. (-1) St. Louis (+3) Cedar Rapids-Waterloo-Dubuque, Iowa (+3) Myrtle Beach-Florence, S.C. (+11) Syracuse, N.Y. (+6) Louisville, Ky. (-2) Greensboro-High Point-Winston Salem, N.C. Lexington, Ky. (-10) Orlando-Daytona Beach-Melbourne, Fla. (-6) Kansas City, Mo. (-1) Miami-Ft. Lauderdale, Fla. (-3) Salt Lake City, Utah Honolulu, Hawaii Las Vegas Portland, Ore.

“We have more people affected by bed bugs in the United States now than ever before,” says Orkin Entomologist and Director of Technical Services Ron Harrison, Ph.D., adding that bed bugs are a growing issue. “They were virtually unheard of in the U.S. 10 years ago,” he says.

“Anyone can get bed bugs in their home. They are not a sign of uncleanliness. Bed bugs only need blood to survive. We have treated for bed bugs in everything from million dollar homes to public housing.”

Bed bugs can be difficult to detect and treat because of their small size and ability to survive up to a year without feeding. They are about the size of an apple seed when fully grown, and can hide around seams of a mattress, behind headboards and in cracks and crevices, usually within a five-foot radius of the bed. The first signs of a bed bug infestation are often the bed bugs themselves or small dark stains bed bugs can leave behind.

“People may have bed bugs and not know it, because many people have no physical reaction to bed bug bites,” Harrison says. “That’s why it’s important for people everywhere to inspect for bed bugs regularly.”

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