The state Department of Health issued a high bacteria advisory today for Ala Moana Beach Park.

The department’s Clean Water Branch detected levels of enterococci that exceeded the threshold, at 1,013 per 100 milliliters, during routine beach monitoring. The elevated level means that potentially harmful microorganisms such as bacteria, viruses, protozoa, or parasites may be present in the water, according to department officials.

“Swimming at beaches with pollution in the water may make you ill,” they said in a news release this afternoon. “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, usually while swimming.”

The most common illness associated with swimming in water polluted by fecal pathogens is gastroenteritis. Symptoms include nausea, vomiting, stomachache, diarrhea, headache or fever, according to the department.

Signs have been posted at Ala Moana Beach Park, and the advisory will remain in effect until water sample results no longer exceed the threshold level of 130 enterococci per 100 milliliters.

Updates on water quality advisories are available online.