Why Soft Cheeses Are Not Recommended for High-Risk Populations
Soft cheeses pose a significant risk of Listeria monocytogenes infection, which causes severe invasive disease with high mortality in immunocompromised persons, pregnant women (who have 10-17 times higher risk), and the elderly—making avoidance of these products a critical food safety measure for these populations. 1, 2
The Core Problem: Listeria Contamination
Soft cheeses are particularly susceptible to Listeria monocytogenes contamination because:
- High moisture content creates an ideal environment for bacterial growth, even in refrigerated conditions 3
- Contamination can occur after pasteurization during processing, making even pasteurized soft cheeses potentially dangerous 4, 5
- The processing environment can harbor Listeria unless stringent hygienic controls are maintained 4
Who Must Avoid Soft Cheeses
Immunocompromised Patients
- HIV-infected persons with CD4+ counts <200 cells/µL should strictly avoid soft cheeses 1
- Cancer chemotherapy recipients and those on long-term immunosuppressive therapy (including anti-TNF agents) are at markedly increased risk 1, 6
- Patients with chronic liver disease (cirrhosis, hemochromatosis) have heightened susceptibility 1
Pregnant Women
- Pregnant women face 10-17 times higher risk of invasive listeriosis compared to the general population 2, 6
- Listeriosis during pregnancy is associated with miscarriage and fetal loss 1, 7
- Between 17-33% of all invasive listeriosis cases occur in pregnant women, fetuses, or newborns 2, 6
Elderly Patients
- Adults ≥65 years are at increased risk for severe invasive disease 8
Specific Soft Cheeses to Avoid
High-risk individuals must avoid the following soft cheeses 1:
Safe Cheese Alternatives
The following cheese products do NOT need to be avoided 1:
- Hard cheeses
- Processed cheeses
- Cream cheese (including slices and spreads)
- Cottage cheese
- Yogurt
Clinical Significance
Disease Severity
- Invasive listeriosis presents as bacteremia and meningitis with high mortality 8
- Symptoms typically begin 1-4 weeks after consuming contaminated food, though can occur from same day to 70 days post-exposure 4
- Treatment requires high-dose IV ampicillin or amoxicillin with gentamicin for synergy 6, 8
Outbreak Data
- Two-thirds of cheese-associated listeriosis outbreaks since 2006 have been linked to Latin-style soft cheeses 5
- Fresh, soft Hispanic-style cheeses made with pasteurized milk remain a well-documented outbreak source despite pasteurization 4, 5
- Hispanic pregnant women and their newborns are disproportionately affected 4, 5
Additional Food Safety Measures for High-Risk Groups
Beyond avoiding soft cheeses, high-risk individuals should 1:
- Avoid unpasteurized dairy products of any kind (milk, cheese, yogurt) 1, 7
- Reheat deli meats and hot dogs until steaming hot before consumption 1
- Avoid foods from delicatessen counters (prepared salads, meats, cheeses) unless reheated until steaming 1
- Avoid refrigerated pâtés and meat spreads unless heated until steaming 1
- Cook all meats thoroughly: poultry to 180°F (82°C) internal temperature, red meats to 165°F (74°C) 1
- Wash hands thoroughly after handling raw foods and before eating 1, 2
- Prevent cross-contamination by keeping raw meats separate from other foods 1
Critical Pitfall to Avoid
Do not assume pasteurized soft cheeses are safe—multiple outbreaks have been linked to soft cheeses made with pasteurized milk due to post-pasteurization contamination during processing 4, 5. The recommendation to avoid soft cheeses applies regardless of pasteurization status for high-risk populations.