The cluster is centered in Carnegie Hill and Yorkville, including ZIP codes 10028, 10128 and 10075. NYC Health said no cases were diagnosed after July 15 and that it is confident the source of Legionella exposure has been eliminated. The department has not publicly identified a definitive cooling tower as the source.

What the cooling-tower testing shows

City officials tested 183 cooling towers at 160 buildings. Initial PCR testing found Legionella in 77 towers at 75 buildings. Culture testing, which confirms the presence of live Legionella bacteria, was positive at 57 towers at 56 buildings.

All culture-positive towers were cleaned and disinfected, and NYC Health says remediation has been completed. A culture-positive result does not by itself prove that a tower caused any patient’s illness. The department says a positive tower may or may not have been the source of exposure in the cluster.

Legionnaires’ disease is generally linked to breathing contaminated water droplets or mist. NYC Health says residents in the affected ZIP codes can continue to drink tap water, shower, cook, bathe and use air conditioning at home. The illness is not spread through drinking water, cooled air from home air conditioners or person-to-person contact.

Why the City Council is asking questions

The New York City Council has announced plans for an oversight hearing in September to examine the city’s response. The Council has not announced a final hearing date in the cited release.

Council members have raised questions about resident notifications, public transparency, building-owner compliance, inspection capacity and enforcement of cooling-tower testing and reporting requirements. The Council is also considering possible legislation that could strengthen public education and notifications, create a hotline during peak summer months, establish a real-time public-health response database, require earlier disinfection and increase inspection capacity.

NYC rules require cooling-tower owners and operators to maintain a maintenance program, monitor water quality, keep records, register systems and report certain information through the city’s portal. The city has said summonses may be issued when inspectors find noncompliance. Those enforcement steps should not be confused with a finding that any particular building caused the outbreak.

What residents should watch

People who live or work in ZIP codes 10028, 10128 and 10075, as well as people who recently visited the area, should monitor NYC Health updates. Anyone experiencing flu-like symptoms such as cough, fever or difficulty breathing should contact a health care provider promptly.

The immediate response has moved into remediation and case monitoring, but questions about notification, records, inspections and enforcement remain. The planned September Council review is expected to focus on whether the city’s cooling-tower oversight and public-health communication systems worked as intended.

Sources

• NYC Health cluster update
• New York City Council outbreak response
• Associated Press outbreak report

The key warning: in these investigations, cases were identified after travelers returned home, and in one outbreak the cluster was recognized only after a report from a member of the public. CDC says those timing and communication gaps can leave other potentially exposed travelers without early notice.

What CDC found

CDC reports that investigators followed up on confirmed Legionnaires’ disease cases tied to two different hotels on St. Croix Island. CDC describes the two hotel outbreaks as unrelated—but the report focuses on what went wrong operationally, not on blaming a single source. In one case, a patient was hospitalized in their U.S. state of residence after returning from travel.

CDC also highlights that the outbreak at one hotel was detected solely through a report from a member of the public. That matters because, unlike a proactive notification to public health, public-report-driven detection can arrive later—after additional exposures may have already happened.

Why the detection delay matters

When people develop pneumonia-like illness days after travel, the chain that connects “symptoms” to “exposure location” can break. CDC notes that many travel-associated cases may be missed among travelers who return home before symptoms develop, and that delays in case identification and underreporting can slow the overall public-health response.

What CDC says should change

CDC frames “what’s changed” as an operational shift: public health and facilities need faster coordination and reporting when travel-associated Legionnaires’ disease cases emerge. In particular, CDC emphasizes the importance of:

• Notifying guests so additional cases can be found during hotel outbreaks.
• Including the destination/hotel information when reporting travel-associated Legionnaires’ disease cases to CDC—supporting multijurisdiction coordination to identify sources sooner.

For hotels and other facilities, the MMWR also points to the need for effective water-management programs and appropriate disinfection/testing to prevent Legionella growth in building water systems.

Practical takeaways for travelers

If you stayed at a hotel in the U.S. Virgin Islands (or elsewhere) and develop cough, fever, or shortness of breath after travel, the MMWR’s message is straightforward: tell your health care provider about your recent travel and where you stayed, so clinicians can consider travel-associated exposure in context and pursue timely testing.

And when you’re booking, you can ask hotels about their Legionella water-management practices—because the CDC’s theme here is that prevention and rapid communication have to work together, before outbreaks are recognized.

Bottom line: CDC’s report shows how Legionnaires’ disease outbreaks can be “missed” when detection happens after guests return home and when information arrives late—reminding travelers and facilities that timing and reporting are part of public health, not just clinical care.

Sources

• CDC MMWR (July 2, 2026): “Legionellosis Outbreaks Associated with Two Hotels — U.S. Virgin Islands, October 2024–April 2025”