Red Tide Is Spreading to Florida’s East Coast. Here’s What to Know About It

Tourists and residents alike have been chased away from Florida's famous beaches by an ominous-sounding ecological occurrence: red tide.

Florida sees red tide — an algae outbreak that can kill marine life and sicken humans — nearly every year, but the current flare-up seems to be spreading toward the state's Atlantic Coast, a rare occurrence that's been documented only nine times in the last 70 years. Here's what to know about red tide in Florida.