The state Health Department this afternoon issued a high bacteria warning for the waters at Koloa Landing in Poipu on Kauai.

Routine beach monitoring detected elevated levels of enterococci. Signs have been posted at the beach, and the advisory will remain in effect until water samples no longer exceed the warning threshold.

When enterococci levels are high, according to the state Health Department, potentially harmful microorganisms such as bacteria, viruses, protozoa, or parasites may be present in the water. Swimming in polluted water may cause illness.

Children, the elderly, and people with weakened immune systems are the most likely populations to develop illnesses or infections after coming into contact with polluted water while swimming. The illnesses, however, are usually not serious and require little or no treatment or get better quickly upon treatment with no long-term health effects.

The most common illness associated with swimming in water polluted by fecal pathogens is gastroenteritis, with one or more of the following symptoms: nausea, vomiting, stomachache, diarrhea, headache or fever. Other minor illnesses associated with swimming in polluted water include ear, eye, nose and throat infections.

Swimmers may be exposed to more serious diseases in highly polluted water.

Updates to the water quality at Koloa Landing are available at this link.