As of Thursday, October 21, 652 people across 37 U.S. states have suffered from recent Salmonella infections, with nearly 130 patients requiring hospitalization. The outbreak, The New York Times reports, has been linked to whole red, white, and yellow onions imported from the State of Chihuahua, Mexico.

Though the FDA and CDC’s joint investigation is still ongoing, it’s unearthed plenty of helpful details already. The onions in question appear to have entered the U.S. between July 1 and August 31 and were then distributed by ProSource Produce LLC and Keeler Family Farms to restaurants, wholesalers, and stores. Both companies have agreed to voluntarily recall all onions imported from Chihuahua during July and August.

Since onions are good for a few months when stored correctly, businesses and individuals alike may still be harboring contaminated ones. The CDC and FDA are urging everyone to trash all onions that came from Chihuahua and were supplied by ProSource or Keeler—as well as any of unknown origin. In other words, unless you’re totally certain that your onions didn’t come from ProSource or Keeler, throw them away. You should also be sure to thoroughly wash any surface or container that may have come into contact with the onions. And, if you’re buying onions from a store or ordering a dish that contains onions at a restaurant, first confirm that they weren’t sourced from either distributor.

Common Salmonella symptoms—diarrhea, fever, and stomach cramps—usually resolve themselves within a week. But more severe cases might require treatment, so call your healthcare provider immediately if you experience dehydration, intense vomiting that prevents you from stomaching liquids, bloody diarrhea, diarrhea that doesn’t improve after a few days, or diarrhea and a fever above 102 degrees Fahrenheit.

Even mild cases of Salmonella illness should be reported to your local health department so officials can track the outbreak. Find out how to do that here.

[h/t The New York Times]