Cyclospora Outbreak Update: Check Walmart Marketside “Best if Used By” Dates for Taylor Farms-Linked Shredded Iceberg Lettuce

Updated FDA guidance: If you bought Marketside shredded iceberg lettuce sold at Walmart, check the label and stop eating any packages that match the affected product formats and “Best if Used By” dates in the FDA’s current investigation update.

This Cyclospora outbreak is linked to shredded iceberg lettuce from Taylor Farms de Mexico. Even though FDA notes a July 18 positive sampling result was later re-reviewed as a false positive, the agency still instructs consumers to remove implicated product from use if the package matches the identifiers below.

What FDA says is implicated

In its outbreak investigation update, the FDA ties Cyclospora illnesses to shredded iceberg lettuce sourced from Taylor Farms de Mexico, and identifies specific consumer-facing products as implicated: Walmart Marketside lettuce items made with that product.

Because this is an outbreak-linked product, the safest approach is not to guess based on “iceberg lettuce in general.” Instead, use the package identifiers and the “Best if Used By” date range provided by FDA.

Your fridge checklist: Marketside products + date range

Use this as your step-by-step check before you toss anything:

1. Find the exact product name/format on the front and/or side of the package. FDA’s investigation update focuses on Marketside iceberg lettuce formats (including iceberg salad and shredded lettuce).
2. Locate the “Best if Used By” date on the package.
3. Compare to the FDA range: 7/18/2026–8/3/2026. If your date falls within that window, do not eat the product.

Important: FDA’s update also explains that a sample positive result from July 18 was later re-reviewed as a false positive. That clarification does not mean shoppers should treat the outbreak as over—FDA still expects consumers to remove implicated product from use when the package matches the identifiers and date range.

Where it may have been sold (distribution update)

In its 8/13/2026 update, FDA refreshed the Stores Affected / distribution footprint. Check the FDA investigation page for the latest state-by-state list of where the implicated products were sold.

If you’re not sure whether your store is included, go by the label first: product name/format and “Best if Used By” dates are the most reliable way to decide.

What to do if you already bought it

If your package matches the implicated Marketside product format and the “Best if Used By” date range:

• Stop eating it immediately.
• Do not serve it to anyone, including “just a little” tasting.
• Throw it away or return it as directed by FDA/retailer guidance in the official update.

The goal is simple: keep the food out of your kitchen and out of anyone’s plate.

What to do if you already opened it or handled it

If you bought the lettuce and opened the package (or scooped or rinsed it), take these kitchen-safe steps:

• Wash your hands with soap and warm water.
• Sanitize surfaces that may have touched the lettuce (countertops, cutting boards, sink areas where it drained, and any utensils used).
• Clean and disinfect storage containers that held the lettuce—don’t reuse them “as is.”
• Discard the packaging and bag the trash sely to avoid re-contamination.

This is a practical way to protect family members while you remove the implicated product from use.

If you already ate it and got sick

Cyclospora infection (sometimes referred to as cyclosporiasis) can cause gastrointestinal illness. If you or someone in your household ate the implicated lettuce and develops symptoms that concern you or are consistent with cyclosporiasis, contact a healthcare provider.

FDA notes the relevant timing window for symptoms can extend beyond the point of eating (so don’t dismiss symptoms just because you ate the lettuce “a while ago”). If symptoms start, it’s worth reaching out promptly and mentioning the food you ate.

Update note: July 18 sample was later re-reviewed

FDA includes an important clarification: a July 18 positive sampling result was later re-reviewed and determined to be a false positive. That affects how the sampling result is interpreted—but it does not change the bottom-line consumer action: if your Walmart Marketside lettuce package matches the implicated format and “Best if Used By” date range, stop eating it and remove it from use.

Calm next step: Pull the package from your fridge, check the exact product name and the date, sanitize any surfaces it touched, and then follow FDA’s instructions for disposal/return.

Sources

• FDA Outbreak Investigation: 9-state Cyclospora illnesses linked to iceberg lettuce (Taylor Farms de Mexico)
• CDC Foodborne Outbreaks Index