An outbreak of Legionnaires’ disease has killed two people in Harlem since it was noticed on July 25th. So far, health authorities have said that 58 people have been diagnosed with the disease since July 25th.

The New York City Health Department provided an update Monday on their investigation into a community cluster of Legionnaires’ in Central Harlem, linked to ZIP codes 10027, 10030, 10035, 10037, and 10039, and bordering communities.

Officials say the remediation required by the department has been completed for the 11 cooling towers, with initial positive screening results showing the presence of Legionella pneumophila, a type of bacteria that causes Legionnaires’ disease. This bacterium also causes Pontiac Fever. People generally do not spread Legionnaires’ or Pontiac Fever to each other.

Water containing Legionella can spread in droplets small enough for people to breathe in. People can get Legionnaires’ disease or Pontiac fever when they inhale (breathe in) those small droplets containing the bacteria. This is the most common way people get sick, according to the Centers for Disease Control and Prevention’s website. 

While less common, people can get sick from aspiration of drinking water containing Legionella. This happens when water accidentally goes into the lungs while drinking. People at increased risk of aspiration include those with swallowing difficulties.

Legionnaires’ disease symptoms usually develop 2 to 14 days after exposure to Legionella bacteria, but the manifestation of this disease can take longer. Symptoms include cough, fever, headaches, muscle aches, and shortness of breath. Other symptoms, such as confusion, diarrhea, or nausea, can also occur.

Legionnaires’ can be treated with antibiotics. Complications of this disease can be mitigated if early treatment is possible.

Health officials have also warned that it’s especially important for people at higher risk, including those ages 50 and older, cigarette smokers, and people with chronic lung disease or compromised immune systems, to get care if they have symptoms.