WEST ORANGE — A North Jersey school district where a bacteria called Legionella was found in the water of most district schools will work to kill it this weekend.

The initial discovery was made in August, when a student attending summer camp at the Redwood Elementary School became sick with what her doctor said may be Legionnaires' Disease, according to a letter send to parents from superintendent Jeffrey S. Rutzky. All the water fountains and sinks were found to be safe in Redwood in accordance with Safe Drinking Water Act standards following tests, Rutzky said.

Subsequent testing for the bacteria in the rest of the district's 11 buildings turned up cases in all but three schools.

Rutzky said a chlorination process will be done in the affected schools water system this weekend to eliminate the bacteria. The procedure requires a weekend to get the job completed.

So far, Rutzky said, there is no reason to close the schools.

“We have been advised of the following facts with regard to Legionella: (a) it is not contagious, person to person; (b) it is not airborne; (c) it cannot be contracted by drinking or touching water; and (d) the way it is contracted is by inhaling contaminated mist," Township Director of Health, Theresa DeNova said in a statement.

Following "significant confusion" about the bacteria, Rutzky issued a statement clarifying that the risk is low from drinking water, washing hands and washing cars.

Legionella occurs naturally in fresh-water environments, like lakes and streams. It can become a health concern when it grows and spreads in human-made building water systems.

People can get sick with Legionnaires Disease when they breathe in mist or accidentally swallow water into the lungs containing Legionella, according to the Centers for Disease Control. Most people exposed to Legionella do not get sick. However, people 50 years or older, current or former smokers, and people with a weakened immune system or chronic disease are at increased risk.

The CDC said about one in 10 people who gets sick from Legionnaires’ disease will die.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ