Multiple city agencies finally jumped into action when faced with The Post’s coverage of that trash-packed Queens house, but why did it take so much publicity? It looks to us like just a fresh, flagrant example of how city government refuses to deal with serious mental illness.

The main evidence of that, of course, is homeless people allowed to live on the streets despite clear signs of schizophrenia and other major disorders. The law allows authorities to take action if the individual poses a menace to himself (it’s typically a male) or others — but too often nothing happens until after violence occurs.

Carmine Bhimull, the super-hoarder tenant, posed a clear public health menace: The refuse she’d piled yards high inside and outside her home literally reeked. One neighbor told The Post, “There is food and fecal matter, the smell in the heat — we had to use Febreze or peppermint oil to get the smell out.”

Green slime dripped from bags she’d put on the roof; neighbors documented multiple large rats attracted by the “feast.”

Only a seriously dysfunctional person produces such a horror — and refuses all effort to help her address it. But city government did nothing but ticket the home until The Post stepped in.

Neighbors called 311, reached out to the local assemblyman and even started petitions — but the city let the situation grow ever worse, year after year after year.

Only after it became Page One news (and, according to Mayor Bill de Blasio, after he personally made phone calls about the situation) did some city employee think psychiatric intervention might be in order.

And so, after Bhimull ranted furiously to sanitation workers who showed up on Wednesday, she finally got taken in for evaluation, while other agencies suddenly found ways around the legal barriers that had previously “prevented” them from moving in to clean up the hazardous waste.

Now the taxpayers are covering the costs of the private workers brought in to do the cleanup. Fitting enough, since this case is all about city government finding ways not to do its job because it just seemed too difficult.