Following Monday’s Brown Water Advisory issued by the Hawaii Department of Health for Waimea Bay, the department’s Clean Water Branch issued a High Bacteria Count Advisory for the beach late Tuesday.

According to DOH, levels of 1298 per 100 mL were detected during routine beach monitoring. Tests for enterococci — a bacterium that lives in the intestines of warm-blooded animals, including humans — indicate that “potentially harmful microorganisms such as bacteria, viruses, protozoa, or parasites may be present in the water,” according to a DOH statement.

Swimming in waters with fecal pathogens in the water could make you ill.

The ones most likely to develop illnesses or infections while in polluted waters include children, the elderly and people with weakened immune systems. However, DOH says that while swimming-related illnesses can be “unpleasant,” they are usually not very serious, requiring little or no treatment, or when treated, individuals recover quickly. There are usually no long-term health effects.

According to DOH, the most common illness associated with swimming in water polluted by fecal pathogens is gastroenteritis. It can take different forms that can have several of these symptoms — nausea, vomiting, stomachache, diarrhea, headache or fever. Other minor illnesses include ear, eye, nose or throat infections. Individuals who swim in highly polluted water may be exposed to more serious diseases.

DOH says other issues could also cause these symptoms such as food poisoning from eating improperly refrigerated food consumed at the beach.

Signs have been posted at Waimea Bay and the advisory will remain in effect until the water sample results no longer exceed 130 enterococci per 100 mL.

For more information, view the advisory or visit the Environmental Protection Agency website for beach-related illnesses.