Water fountains in six St. John the Baptist Parish public schools were turned off Friday after state health officials this week confirmed the presence of a rare brain-eating amoeba in one area of the parish’s water lines.

Meanwhile, parish officials have increased chlorine levels in the water system after tests conducted by the Louisiana Department of Health and Hospitals indicated the single-celled organisms were present in water lines that service St. John’s Water District No. 1, which includes about 12,500 residents in Garyville, Mount Airy, Reserve and a small part of LaPlace — the area between Acorn and Apricot streets on West Fifth Street.

The amoeba, known as Naegleria fowleri, has been linked to the deaths of three people in Louisiana since 2011. However, no cases of illness related to the most recent confirmation of the amoeba have been reported in St. John or elsewhere, officials said Thursday.

Because Naegleria fowleri cannot be contracted by drinking the water, public health officials said the local water supply remains safe to consume. Most people who contract the disease — a total of 32 nationwide from 2001 to 2010 — did so after swimming in bodies of warm fresh water and ingesting contaminated water through their noses. When infections occur, the water containing the amoeba enters the body through the nose and is pushed into the brain.

Schools spokeswoman Jennifer Boquet said the water fountains were shut down out of an abundance of caution.

Water District No. 1 includes these schools: St. John Child Development Center, Garyville-Mount Airy Math and Science Magnet, East St. John High, Fifth Ward Elementary, Lake Pontchartrain Elementary and East St. John Elementary.