Legionnaires’ Disease Outbreak in Central Harlem

New York City is currently facing an outbreak of Legionnaires’ disease in Central Harlem. So far, this illness has claimed three lives and infected dozens of others. Unfortunately, this isn’t the first time we’ve seen similar outbreaks; they tend to surface during the summer months.

Experts in Legionnaires’ disease suggest that a mix of environmental and human factors may explain the recent surge in cases, both locally and nationwide. There’s greater awareness of Legionnaires’— a serious type of pneumonia— as well as issues related to climate change and the management of building water systems. To get the disease, a person must inhale water vapor or mist that contains the Legionella bacteria, which often grows in plumbing and cooling towers.

New York isn’t alone in dealing with outbreaks, but the state stands out for the frequency of cases. The worst outbreak in the city’s history happened in the South Bronx in 2015, affecting over 130 individuals and resulting in 16 fatalities. That incident prompted both city and state authorities to implement measures aimed at controlling Legionella growth in water systems.

Despite these regulations, the city health department continues to report hundreds of cases each year. For instance, last year, 257 people in New York were diagnosed with Legionnaires’ disease, and in 2018, that number exceeded 650. Over the past decade, various outbreaks have also led to additional deaths, including five individuals from a nursing home outbreak in 2022.

Data indicates that annual cases of Legionnaires’ have surged since 2000. While New York and several other Northeastern states report high case rates, the disease is rarely seen on the West Coast, according to the U.S. Centers for Disease Control and Prevention.

High-poverty neighborhoods in New York City, where health issues like asthma are more common, appear to be disproportionately affected by Legionnaires’, according to city statistics.

A Personal Experience with the Illness

Anita Long fell ill with Legionnaires’ disease in 2022 after residing in the Bronx for over 30 years.

“I loved my area,” Long, now 68, recalled. As a former member of Bronx Community Board 4 and a tenants’ rights advocate, she had deep roots in her community.

However, complications from her illness led to a 22-day hospital stay, after which she developed a fear of going outside, worried about another bout of illness. According to medical experts, infections tend to occur when people inhale bacteria-contaminated droplets outside.

“This was one of the factors that made me relocate to Connecticut,” Long expressed, voicing concerns about the maintenance of cooling towers in her former neighborhood.

Increased awareness in the medical field is another possible reason for more diagnoses lately. “Physicians are more alert to Legionnaires’ disease when they see pneumonia cases,” noted Janet Stout, an infectious disease microbiologist.

In New York City, the health department actively keeps Legionnaires’ in medical discussions. A notice to healthcare providers reminded them that New York has a high burden of legionellosis, particularly during the summer and early fall.

Factors Behind the Increase

Legionella bacteria thrive in warm water, and researchers suggest that rising temperatures may be contributing to the increasing number of cases over recent decades. Stout pointed out that areas with high humidity and less sunlight are especially favorable to Legionella during the summer months.

Additionally, New York’s aging infrastructure and high sediment levels in the water can provide a “food source” for the bacteria, according to David Pierre, director of water safety programs at LiquiTech.

Researchers continue to explore why Legionnaires’ disease has become more prevalent in recent years. Interestingly, a 2022 study from the University of Albany suggests that reducing sulfur dioxide levels in the air might inadvertently benefit Legionella bacteria, allowing them to survive for longer periods.

While improved air quality is generally positive, the researchers indicate this might be an unintended consequence that needs further examination. Stout described it as an intriguing finding worth studying.

Experts agree that New York City’s dense population means that when a cooling tower emits Legionella, more individuals are likely to be exposed, yet not everyone who encounters the bacteria falls ill. Demographics play a crucial role; most Legionnaires’ cases in the city involve individuals with at least one risk factor, such as being over 50 years old, having a smoking history, or suffering from chronic lung disease.

Prevention Measures

Despite the many contributing factors, experts stress that Legionnaires’ disease is largely preventable if building owners take appropriate actions to manage and test for Legionella. They argue that New York City’s and state’s existing protocols, if properly implemented, should be effective.

“New York State and New York City have made significant efforts compared to other states and cities regarding Legionnaires’ disease prevention,” Stout emphasized. “Yet, outbreaks still happen, primarily due to human factors.”

State law mandates that hospitals and residential care facilities create sampling and management plans for controlling Legionella in their water systems.

Under a city law passed in 2015, all building owners are required to register their cooling towers and establish maintenance plans to prevent Legionella growth, with inspections at least every three months.

The city is also authorized to conduct its own inspections, and violations could lead to fines or misdemeanor charges. City protocols are based on a national standard from the American Society of Heating, Refrigerating and Air Conditioning Engineers.

However, reports show a significant drop in city cooling tower inspections since the law took effect. Last week, when asked about the decline, the health department attributed it to staffing shortages.

Additionally, Pierre mentioned that some property owners might only do the bare minimum to comply with regulations, risking inadequate maintenance.

City health officials have implemented aggressive measures to stop the ongoing Harlem outbreak. They are screening all water cooling towers in the area and have initiated remediation efforts at 11 buildings that tested positive for Legionella.

So far, officials haven’t confirmed a direct link between the positive tests and the current outbreak.