We've known this for years. Actually though, on the substantive point, the infestation is being blamed on "neglect at the building".
This is unlikely to be just simple "neglect" - rats need access to flowing water. As a rule of thumb, you can say with almost complete confidence that, if you have a rat problem in a building, there is a drain or sewer defect. This should not be happening. Read what I said about it in 2008 - just as relevant now.