Swimmers are being advised to stay out of the water at 12 Miami-Dade beaches.

That's according to health officials, who have found bacteria levels that exceed state standards at the beaches and issued a no-swim advisory.

Tests were performed on the ocean water earlier this week, and county officials are expected to review more tests Thursday to decide whether the warnings should remain in place.

An environmental administrator for the Miami-Dade County Health Department says swimmers who ignore the warnings might be at a greater risk of gastrointestinal illness and ear and eye infections.