UPPER EAST SIDE — The New York City Health Department declared that there is no longer an elevated risk of Legionnaires' disease on the Upper East Side in late July 2026. Health officials confirmed the source of the Legionnaires' disease community cluster has been eliminated.

Seven people have died in connection with the Legionnaires' disease outbreak on the Upper East Side. Ninety-two people have been diagnosed with Legionnaires' disease as a result of the Upper East Side cluster.

"We can confirm the source of this Legionnaires’ disease community cluster has been eliminated," NYC Health Commissioner Alister Martin said. "As a result of our strict enforcement and our swift action we can confirm the source of this Legionnaires’ disease community cluster has been eliminated."

Martin added that the intervention removed the immediate threat to residents in the affected neighborhoods. "There is no longer an elevated risk of Legionnaires’ disease in the three ZIP codes," he said.

The affected area includes ZIP codes 10028, 10075, and 10128. The outbreak was first identified on July 2.

More than 90% of patients began experiencing symptoms before July 7. No new cases of Legionnaires' disease linked to the cluster have been reported since July 17.

Seventy-nine people were hospitalized during the outbreak. Five people remain hospitalized with Legionnaires' disease as of July 30.

Legionnaires' disease is a severe form of pneumonia caused by breathing in mist containing Legionella bacteria. The illness is not contagious.

The health department tested 183 cooling towers at 160 buildings in the affected area. Initial PCR screening detected signs of Legionella bacteria in 77 towers at 75 buildings.

Culture testing confirmed the presence of live Legionella bacteria in 59 towers at 58 buildings. The city ordered 83 buildings to fully drain, clean, and disinfect their cooling towers.

Every building ordered to remediate its cooling tower complied with the order. Inspectors completed inspections of 82 cooling towers that tested positive through either PCR screening or confirmatory culture testing.

Sixty percent of the completed inspections resulted in at least one violation, producing more than 110 violations overall. The violations included more than 15 public-health hazards, more than 50 critical violations, and more than 40 general violations.

The cooling tower at 300 E. 83rd St. had the most violations, with 11 citations and $11,000 in fines issued to the owners. The cooling tower at 1520 York Ave. had the second-highest number of violations, with nine citations and $9,000 in fines issued.

"We are saddened to share that a seventh person has died from Legionnaires’ on the Upper East Side," Health Commissioner Alister he said. "That is seven deaths too many."

Martin offered sympathy to those affected by the cluster. "We extend our heartfelt condolences to their loved ones, and our thoughts are with them during this difficult time," he said.

Whole-genome sequencing is underway to compare bacterial samples from patients with samples from cooling towers. Results from whole-genome sequencing are expected by the end of August.

City Council Speaker Julie Menin announced plans for an oversight hearing in September and new legislation to strengthen public notification and education. PureSource News previously reported that the health department ordered 19 Manhattan buildings to disinfect cooling towers after the outbreak began.

The declaration ends a period of heightened public health alert in three Upper East Side ZIP codes where 92 residents contracted a severe form of pneumonia. The response involved testing 183 cooling towers and issuing over 110 violations for conditions that posed public-health hazards.

While the immediate risk has been normalized, the death toll of seven reflects the severity of the cluster. Ongoing whole-genome sequencing will determine if patient samples match bacteria found in specific towers, and legislative proposals aim to adjust how the public receives notification during future outbreaks.

Why It Matters

The elimination of the bacterial source ends an elevated risk for residents in three ZIP codes where 92 people contracted the illness and seven died. While no new cases have emerged since mid-July, five patients remain hospitalized, showing the outbreak's lasting physical toll. The identification of over 110 violations across inspected cooling towers establishes a documented record of infrastructure failures that prompted the cluster. Upcoming legislative proposals and genomic sequencing results could further alter building compliance standards and public notification protocols.