The latest list of top bed-bug cities released by Orkin today shows Dayton’s bed-bug problem is worsening, while Cincinnati’s has improved.

Dayton now ranks No. 11 on the list, moving up four spots from 2011. Cincinnati is now at No. 5 – it was No. 1 in 2011.

Chicago is now No. 1 for having the highest number of bed bug treatments by Orkin from January 2011, according to a release.

Orkin’s parent company, Rollins, operates eight pest control brands nationwide and announced it saw a 33 percent increase in bed bug business compared to 2011.

Cities making significant jumps include Seattle/Tacoma, Indianapolis, Omaha, Milwaukee, Hartford/New Haven, Knoxville, Charleston/Huntington, Cedar Rapids/Waterloo and Minneapolis.

Showing improvement were some popular vacation destinations, including Atlanta, Honolulu, Charlotte and Las Vegas.

The following cities are ranked in order of the number of bed bug treatments Orkin performed in 2012.

1. Chicago (+1)

2. Detroit (+1)

3. Los Angeles (+2)

4. Denver

5. Cincinnati (-4)

6. Columbus, Ohio

7. Washington D.C. (+1)

8. Cleveland/Akron/Canton (+5)

9. Dallas/Fort Worth (-2)

10. New York (-1)

11. Dayton, Ohio (+4)

12. Richmond/Petersburg, Va. (-2)