The multistate Listeria outbreak linked to Clover Hill Dairy soft cheese has grown again.
As of June 24, 2026, the CDC and FDA have confirmed 12 people infected with the outbreak strain of Listeria monocytogenes across four states — a net increase of three cases since the previous update on June 18. Illinois is a newly confirmed state, expanding the outbreak's geographic reach beyond the previously affected three states of Maryland, New York, and Virginia.
The case count by state is now: Illinois (1), Maryland (3), New York (5), and Virginia (3). Ten of the 12 confirmed patients have been hospitalized. One person — from Maryland — has died.
The CDC has explicitly stated that the true number of sick people in this outbreak is likely higher than what has been confirmed — a standard caveat for Listeria outbreaks because many cases are never diagnosed, particularly in people who recover from milder illness before seeking care.
Why This Matters
Listeria monocytogenes is one of the most dangerous foodborne bacteria — not because it is common, but because it is lethal when it strikes. The CDC estimates approximately 20 percent of people who develop listeriosis die from it, compared to under 1 percent for Salmonella. Every year, roughly 1,600 Americans develop listeriosis and approximately 260 die.
What makes this outbreak particularly alarming is its timeline: illness samples span March 6, 2023, through June 2, 2026 — more than three years. This means Clover Hill Dairy's cheese has been causing Listeria infections for years without detection, and the contamination was deeply embedded in the production environment.
Patient ages range from 16 to 81 years, with a median age of 55. The majority of patients who provided demographic information identified as Hispanic — consistent with requeson being a staple soft cheese in many Hispanic households, particularly where it may be obtained from farmers markets and small retailers.
What We Know So Far
According to the FDA's outbreak investigation page, the outbreak was identified through the PulseNet system, which uses whole genome sequencing to connect genetically related cases. The outbreak strain was confirmed in six samples of requeson cheese and in one environmental sample collected from inside Clover Hill Dairy's Mechanicsville, Maryland facility.
The environmental match — the same Listeria strain in both the cheese and the facility's production environment — indicates that contamination originated within the dairy itself and was not a post-production event. The Maryland Department of Health suspended Clover Hill Dairy's operating license. All cheese from the facility was recalled on June 18, 2026.
The specific trigger for the traceback: in late May 2026, two related cases from a single family in Suffolk County, New York, were reported to state agriculture officials. Testing of cheese samples found Listeria in repackaged requeson from their retailer; an unopened 18-pound bulk container of Clover Hill Dairy requeson also tested positive. These findings prompted the initial recall, which was expanded to all Clover Hill Dairy products as additional evidence mounted.
The Recall: What Consumers Need to Know
All Clover Hill Dairy cheese products currently on the market have been recalled. The dairy's cheese reaches consumers under multiple brand names and through multiple channels:
Known brand names for Clover Hill Dairy products:
- Kesso
- Quesos La Ricura
- Izalco
- De Mi Pueblo
- Rio Lindo
- Direct Clover Hill Dairy label
How to identify the manufacturer: Look for permit number 24-128 on the package. This identifies Clover Hill Dairy as the manufacturer regardless of the brand name displayed.
Distribution states confirmed: Maryland, New Jersey, New York, North Carolina, Virginia, and Washington, D.C. The outbreak has now confirmed cases in Illinois, which suggests the distribution footprint may extend beyond the confirmed states.
Additional recall: Nelson & Isa Lacteos, LLC of Bay Shore, New York also recalled one-pound plastic clamshell containers of requeson sold at retail locations in New York from May 15 to May 28, 2026.
A Critical Fact About Listeria Most Consumers Don't Know
Listeria can grow and survive in refrigerators. Standard refrigerator temperatures (34–40°F) do not kill Listeria — they actually allow it to thrive over time. This means that simply discarding the recalled cheese is not sufficient.
Any surface, drawer, shelf, door gasket, or other food that came into contact with recalled Clover Hill Dairy cheese in the refrigerator may harbor live Listeria and requires thorough decontamination.
The CDC's recommended refrigerator cleaning protocol:
- Remove and discard all recalled products (sealed in a bag before disposing).
- Remove all food from the refrigerator.
- Wash all interior surfaces with hot soapy water.
- Sanitize with a solution of 1 tablespoon of liquid chlorine bleach per gallon of water.
- Thoroughly clean door gaskets and rubber seals, where Listeria can hide in crevices.
- Wash the exteriors of containers and jars that were stored near the recalled cheese before returning them to the refrigerator.
Who Faces the Greatest Risk?
Listeria disproportionately endangers:
- Pregnant people — even mild maternal illness can cause miscarriage, stillbirth, premature delivery, or severe neonatal infection
- Adults 65 and older — highest case fatality rates from invasive listeriosis
- Immunocompromised individuals — including those with cancer, HIV, organ transplants, or on immunosuppressive medications
- Newborns infected around the time of birth
The one confirmed death in this outbreak was from Maryland. The 10-case hospitalization rate (out of 12 confirmed) is extraordinarily high — reflecting the severity of invasive listeriosis in susceptible populations.
Symptoms and When to Seek Care
Listeria has the longest incubation window of virtually any foodborne pathogen: symptoms can appear as early as the same day of exposure or as late as 70 days afterward.
Mild symptoms: fever, muscle aches, nausea, fatigue, diarrhea.
Invasive disease symptoms (more serious): severe headache, stiff neck, confusion, loss of balance, convulsions.
In pregnant women, Listeria often presents with only fever, muscle aches, and fatigue — appearing flu-like while potentially causing serious harm to the pregnancy.
Anyone in a high-risk group who has consumed Clover Hill Dairy cheese products — even weeks ago — should contact a health care provider now, regardless of whether symptoms are present. Do not wait for symptoms to appear.
What You Can Do Now
- Check all cheese in your refrigerator for permit number 24-128 on the label, or any of the known brand names listed above.
- Discard any Clover Hill Dairy cheese immediately — all varieties are recalled.
- Complete the five-step refrigerator cleaning and sanitization protocol described above.
- If you are pregnant, over 65, or immunocompromised and have consumed any Clover Hill Dairy cheese in the past 70 days, contact your health care provider today, even without symptoms.
- Contact 240-528-8850, extension 327, Monday through Friday 8 a.m. to 4:30 p.m. ET for refund information.
- Report illness to your state health department or the FDA's MedWatch portal.
What Happens Next
The FDA's investigation is ongoing and additional products may be implicated. The distribution footprint may be broader than currently confirmed — the new Illinois case is the first indication of potential reach beyond the originally identified states. MedicalDaily will report on new case counts, additional recall expansions, and the FDA's investigation findings as they are released.
The Bottom Line
The Clover Hill Dairy Listeria outbreak is growing. Three new cases — including the first in Illinois — bring the total to 12 confirmed infections, 10 hospitalizations, and 1 death. The actual case count is almost certainly higher. All Clover Hill Dairy cheese is recalled. Discarding the product is necessary but not sufficient, clean your refrigerator with the CDC's bleach protocol. If you are pregnant, elderly, or immunocompromised and consumed this cheese in the past 70 days, call your doctor now.
