Last year, soon after a Legionnaires’ disease outbreak in Harlem infected 118 New Yorkers and claimed seven lives, the City Council took action.

We voted to triple the frequency of required testing for Legionella in building cooling towers, increasing it from quarterly to monthly, because we believed that this city owes New Yorkers better protection. 

Less than a year later, another outbreak has swept through Manhattan’s densely populated Upper East Side.

At least 74 people have been infected, seven remain hospitalized — and four New Yorkers have tragically lost their lives. 

Their families deserve our deepest condolences.

And they also deserve something more: real answers from Mayor Zohran Mamdani’s administration.  

Legionnaires’ disease is no mystery.

We know how it spreads, and we know how to reduce the risk. 

But even though the council strengthened the law months ago, the administration failed to match those reforms with the urgency, transparency and leadership New Yorkers need. 

Moreover, this month’s outbreak exposed a different set of failures that go beyond lack of sufficient testing.

Throughout this outbreak, New Yorkers were too often left in the dark by a Health Department that didn’t promptly disclose which buildings had tested positive for Legionella, and that neglected its responsibility to  provide guidance to those in the affected neighborhoods. 

Worse yet, the city missed critical opportunities to prevent additional infections.

I repeatedly called on the Health Department to proactively disinfect cooling towers throughout the affected area while investigators worked to identify the precise source of the bacteria, to no avail.

Instead, the department chose to wait — and the crisis spread.  

Equally troubling is the apparent communication breakdown between the Health Department and city hospitals.

Elected leaders learned of the outbreak’s second death through news reports, not directly from the Health Department — and when I requested confirmation, department officials indicated they had first heard of the death through the media as well.

It took hours before the information could be verified.  

That’s deeply concerning: During a public health emergency, hospitals and the Health Department should be in constant contact.  

On top of that, we learned this week that the city lacks sufficient staff to properly respond to this summer’s outbreak. 

The Health Department’s roster of water ecologists –– the very workers who act on positive Legionella findings — currently has at least 20 vacancies, more than a third of this crucial work force.

Local 3005, the union representing these staffers, has pleaded with the administration to address this unacceptable gap immediately, and I join them in that call.  

The epidemiologists, inspectors, scientists and front-line public servants who worked tirelessly throughout this outbreak deserve our appreciation.

These failures are not on them.

But public health depends on public trust — and public trust depends on timely, transparent communication and action. 

This outbreak exposed a dangerous gap between what our laws require and how the city executes them.

 We strengthened the law after the Harlem outbreak, yet City Hall’s response still fell short. 

The council will now act again. 

We are introducing legislation that will establish a dedicated summer hotline so New Yorkers can receive real-time answers during an outbreak, and strengthen requirements for public notification and education.

The proposed law will also require the city to take action on identifying and disinfecting buildings that don’t comply with cooling-tower inspection requirements, and to improve coordination with the Buildings Department.  

And in September, the council will hold an oversight hearing to fully examine the administration’s response. 

The Upper East Side outbreak appears to be slowing, but our responsibility doesn’t end when case counts decline. 

The next outbreak isn’t a question of if, but when — and a question, too, of whether the city will learn from the failures of this one. 

We owe it to the families who have lost loved ones, and to every New Yorker, to make sure we do. 

Julie Menin is speaker of the New York City Council and represents the Upper East Side as council member for District 5.