Seventy beaches in Massachusetts were closed as of early Monday due to unsafe bacteria levels.
State officials required locales to post "no swimming" signs at the affected beaches.
The unsafe bacteria levels came days after heavy rains in Massachusetts. It is not uncommon for bacteria and human waste levels to rise on beaches after periods of heavy rain.
"Swimming or ingesting contaminated water could result in symptoms like nausea, diarrhea, stomach cramps, chills or fever," the city of Revere said after closing its beach. "If you are concerned about your potential exposure to contaminated water when signage is posted, please contact your healthcare provider."
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The Environmental Protection Agency says children, the elderly and people with weakened immune systems are the most likely populations to develop illnesses when exposed to contaminated water.
Although it is unpleasant, the EPA says most of the time, symptoms resolve themselves within days.
More heavy rain is expected for New England in the coming days, which could cause beaches to remain closed during the heart of summer.
A full list of closed beaches is available through the state's Department of Public Health.
