According to reports, on Monday, officials said seven people in the Morris Park area of the Bronx suffer from Legionnaires’ disease. This points to need of an investigation into the possible source of the disease.

According to Dr. Jay Varma, deputy commissioner for disease control at the New York City Department of Health and Mental Hygiene, all seven patients were having underlying medical conditions and have been hospitalized.

Dr. Varma said the cluster of cases was not linked to the disease’s outbreak in July and August that took 12 lives and sickened over 120 people in the South Bronx.

The outbreak prompted a host of legislative and regulatory efforts to assist in preventing the disease, together with a new measure that requires building owners to carry out quarterly checks of cooling towers, and to declare that their towers have been tested, inspected, cleaned and disinfected.

Dr. Varma said those new regulations had assisted in accelerating the investigation into the cases in the Morris Park area. Legionnaires’ disease is a result of the bacteria Legionella that is found throughout the environment.

Each year, some 300 cases of the disease are reported in New York City. Clusters such as the one in Morris Park are rarer as two to 10 such cases are tracked once a year.

According to the health department, “Most cases of Legionnaires’ disease can be traced to plumbing systems where conditions are favorable for Legionella growth, such as whirlpool spas, hot tubs, humidifiers, hot water tanks, cooling towers and evaporative condensers of large air-conditioning systems”.

The genus Legionella is a pathogenic group of Gram-negative bacteria that includes the species L. pneumophila, causing legionellosis (all illnesses caused by Legionella) including a pneumonia-type illness called Legionnaires' disease and a mild flu-like illness called Pontiac fever.