A 54-year-old woman is dead and at least 23 other people are sick after attending an Ohio church potluck luncheon, where health officials suspect patrons dined on food contaminated with the bacterium that causes botulism.

As many as 60 people attended the event Sunday at the Cross Pointe Free Will Baptist Church in Lancaster, about 30 miles southeast of Columbus, Ohio. By Tuesday, many were showing symptoms of botulism, Jennifer Valentine, a spokeswoman for the Fairfield Department of Health, told Reuters. Those symptoms include double or blurred vision, drooping eyelids, slurred speech and difficulty swallowing.

The Centers for Disease Control and Prevention (CDC) quickly sent a large quantity of botulism antitoxin to hospitals where people were being treated, and health officials administered it to people showing symptoms, Reuters reported.

What is botulism?

Botulism is a rare but serious paralytic illness caused by a nerve toxin produced by the bacterium Clostridium botulinum, according to the CDC. About 145 cases are reported each year in the United States, and of those, 15 percent are foodborne. (The others involve wound botulism and infant botulism caused by consuming the spores of the botulinum bacteria, which then grow in the intestines and release toxin.) The CDC says most food-related cases are caused by improperly home-canned foods.

Related: How to Can Food Without Contaminating It

With foodborne botulism, symptoms generally begin showing 18 to 36 hours after eating tainted food, the CDC says. Without treatment, botulism can lead to paralysis of the respiratory muscles, arms, legs and core.

In the past 50 years, the number of people with botulism who die has fallen from 50 percent to only 3 to 5 percent, according to the CDC. Patients who survive may have fatigue and shortness of breath for years.

Related: 10 Food Safety Fails That Can Make You Sick

How to prevent it

Foods with low acid content, such as asparagus, green beans, beets and corn, are the riskiest when it comes to home canning, the CDC says, because there’s not enough acid in the food to kill off bacteria. If you're canning these types of foods, use a pressure canner — a specially designed pot that uses a pressure weight to heat the contents up to 240 degrees F (or higher) for a longer period of time.

Since botulism is destroyed by high temperatures, consider boiling home-canned foods for 10 minutes before eating to make sure they’re safe, the CDC advises.

The CDC also recommends keeping oils infused with garlic or herbs in the refrigerator, not in the pantry or on the kitchen counter. And if you bake potatoes wrapped in foil, keep them hot until served or refrigerate them.

The US Department of Agriculture says to never taste or eat food from leaking, bulging or badly dented cans, or from jars with loose or bulging lids. If you see a badly dented can at the grocery store, look for another can.

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Angela is a Pulitzer Prize-winning digital editor with more than 15 years of experience delivering news and information to audiences worldwide. Prior to joining SafeBee, she was the features editor for Boston.com at The Boston Globe, overseeing health, travel, entertainment, business and lifestyle coverage. Before moving to features, she was the news and homepage editor, covering stories such as the Boston Marathon bombing, Red Sox World Series victories, presidential elections, a papal inauguration, and more. Her favorite safety tip: Clean your phone! The average cell phone has 18 times more germs than the toilet handle in a men’s restroom.