NEW YORK (CBSNewYork) — The city on Thursday the outbreak of Legionnaires’ disease in the Bronx has been contained — the same day the City Council approved sweeping legislation to prevent future problems.

The City Council voted Thursday to approve new regulations to force building owners to register and inspect their cooling towers as the outbreak continues to spread.

Nine new sites have tested positive for the bacteria that cause the disease. Three of those are in the impact zone in the South Bronx, but the other six are outside the infected area.

A total of 12 people have died in the South Bronx outbreak, and the number of confirmed cases of infection has risen to 120. But there have been no new cases with onset of symptoms since Aug. 3, officials said.

Mayor Bill de Blasio thanked workers on the front line at Lincoln Medical and Mental Health Center, who treated 48 patients with legionnaires — including 19 who ended up in ICU but have recovered, CBS2’s Tony Aiello reported.

City health officials are breathing a sigh of relief after no new cases have surfaced in 10 days, Aiello reported.

“We have contained the outbreak of legionnaires in the South Bronx, and this took the work of many,” said city Health Commissioner Dr. Mary Bassett.

“We don’t know the buildings where there are cooling towers,” said City Councilwoman Vanessa Gibson (D-16th), whose district includes part of the South Bronx. “We don’t know the process, the mechanism by which building owners are cleaning, maintaining or even inspecting their cooling towers to begin with.”

Health officials believe it stems from Legionella bacteria festering in building cooling towers, and then sprayed out in a mist.

“We’re in the midst of an emergency in New York City, and this legislation is the proper course of action to deal with a crisis of this magnitude,” said City Council Speaker Melissa Mark-Viverito.

The law would mean all cooling towers would have to be registered with the city and regular testing and cleaning would be required.

Building owners would also need to have cooling towers inspected quarterly and get an annual certification.

Building owners who do not comply would face fins up to $5,000.

The disease is caused when water contaminated with a certain bacteria is inhaled into the lungs.

It is not contagious, and is easily diagnosed and treated with antibiotics, but poses the most risk to people who have underlying medical conditions.

Symptoms of Legionnaires’ disease include headache, fatigue, loss of appetite, confusion and diarrhea.

City Council members hope the new law will prevent future outbreaks.

“We’re going to have this registry, we’re going to require a maintenance plan, we’re going to require constant checking of these systems, every three months,” Mark-Viverito said earlier this week. “I think this is a really important step. We should be really proud.”

A federal expert says the legislation it puts New York City in the forefront of legionella prevention – and gives high marks to the city’s overall response, Aiello reported.

Critics, including Comptroller Scott Stringer, have complained the city was slow to respond to the outbreak.

In response the city released supportive statements from a half-dozen experts.

And the mayor said listen to the experts, not the politicians.