In 2015, New York City earned the unenviable distinction of recording the worst Legionnaires’ disease outbreak in the state's history. After the dust settled, a total of 16 deaths and 133 infections were recorded, prompting state and city officials to take decisive steps to curb the spread of the disease.

The worst may be far from over.

According to the Alliance to Prevent Legionnaires' Disease or APLD, a non-profit organisation which counts healthcare professionals, engineers, and water safety and treatment professionals, the number of recorded cases of the disease continues to climb steadily.

In fact, in 2017, the city recorded 441 cases, equivalent to a 64 percent increase from 2016 when a total 268 cases were reported.

What is even alarming is the fact that NYC's situation becomes graver when compared to state statistics. The total number of cases recorded in the city accounts for roughly 44 percent of the state total. Worse, the record is the highest in the United States.

However, state and city officials reasoned out that the massive spike in the number of recorded Legionnaires' disease occurrences in New York City can be partially attributed to the increased awareness of residents, coupled with improved testing and risk assessment for Legionella, and a massive overhaul of the city's reporting system.

Officials added that compared to other parts of the country, NYC boasts of an aggressive campaign when it comes to following up on reported cases of the disease.

In response to the Legionella outbreak in the Bronx area in 2015, the state's Department of Health has conducted regular checks on both cooling towers and drinking water systems in health care facilities. During this outbreak, about 57 percent of the cases where traced backed to health care facilities.

However, advocacy groups like the APLD say that the actions of the state and local units should not stop at just monitoring cooling towers and drinking systems. These groups argue that equal attention should be given to monitoring public water systems, which carry water into residences and commercial spaces.

According to available data, 35 percent of the reported cases of Legionnaires' disease can be traced back to the contamination of public water systems.

Additionally, APLD enjoined state and local officials to take a proactive stance in its approach to stopping Legionnaires' disease instead of simply reacting to outbreaks.

Such an approach entails a holistic and systematic focus on every aspect of potential sources of contamination – from water distribution to consumption.