Why Are Some People More Susceptible to Foodborne Pathogens – Like E. coli or Listeria?
Foodborne illness doesn’t affect everyone equally. While many healthy adults can recover from a bout of food poisoning in a few days with mild symptoms, others can become gravely ill, or even die, from consuming the same contaminated food. So, why are some people more susceptible to foodborne pathogens than others?
The answer lies in the complex interaction between a person’s immune system, age, health status, and even genetics. Certain individuals are far more vulnerable to the effects of foodborne bacteria, viruses, and parasites, making it essential to understand who’s at higher risk and why.
The Role of the Immune System
At the core of susceptibility is the immune system. A healthy immune system can recognize and destroy many pathogens before they cause serious illness. However, individuals with compromised or underdeveloped immune systems cannot mount the same defense. As a result, pathogens that might cause mild symptoms in one person can lead to severe illness, hospitalization, or death in another.
High-Risk Groups for Foodborne Illness
Public health agencies like the CDC identify several groups as being at increased risk of serious foodborne illness:
1. Infants and Young Children
Children under 5 are particularly vulnerable because their immune systems are still developing. Additionally, their stomachs produce less acid than adults’, making it easier for pathogens to survive and cause infection. Children are also more likely to suffer severe dehydration from vomiting or diarrhea, which can escalate quickly into a medical emergency.
2. Older Adults
As we age, our immune function naturally declines. The body’s ability to recognize and destroy pathogens weakens, and recovery takes longer. Older adults are also more likely to have underlying health conditions, such as diabetes or heart disease, which can further compromise their ability to fight off infection.
3. Pregnant Individuals
Pregnancy brings about hormonal and immune changes that make pregnant people more susceptible to certain pathogens, especially Listeria monocytogenes, which can cause miscarriage, stillbirth, or severe illness in newborns. In fact, pregnant individuals are 10 times more likely to get listeriosis than the general population.
4. People with Weakened Immune Systems
This includes people undergoing chemotherapy, those living with HIV/AIDS, transplant recipients on immunosuppressants, and individuals with autoimmune diseases. Their compromised immune systems can’t respond effectively to pathogens, making even minor exposures potentially dangerous.
Common Foodborne Pathogens and Their Impact
According to one prominent food poisoning lawyer, “certain pathogens pose a greater threat to high-risk individuals” – she noted, in particular:
- Listeria monocytogenes: Particularly dangerous for pregnant people, newborns, and the elderly.
- Salmonella: Can cause bloodstream infections and complications in immunocompromised individuals.
- E. coli O157:H7: Known for causing hemolytic uremic syndrome (HUS) in children, leading to kidney failure.
- Norovirus: Usually causes mild illness but can lead to severe dehydration in vulnerable populations.
- Campylobacter: May cause severe intestinal infections and, in rare cases, neurological complications like Guillain-Barré syndrome.
Even low doses of these pathogens can cause serious illness in high-risk individuals, unlike in healthy adults, who may need a much higher exposure to experience symptoms.
Underlying Conditions and Medication Use
Certain chronic diseases such as diabetes, kidney disease, or cancer increase susceptibility by weakening the immune response or altering the gut microbiome. Similarly, medications like corticosteroids, antacids, or chemotherapy drugs can suppress the immune system or reduce the body’s natural defenses, like stomach acid, which normally kills many pathogens before they reach the intestines.
Socioeconomic and Environmental Factors
Susceptibility isn’t just biological, it’s also shaped by access to safe food, clean water, and healthcare. Individuals living in food-insecure or low-resource environments may face increased exposure to unsafe food or lack the means to store, cook, or preserve food properly. In such settings, even minor contamination can have serious consequences.
Crowded housing, limited refrigeration, and reduced access to information about food safety practices can all increase the risk of exposure and illness.
Prevention Strategies for High-Risk Individuals
For those more susceptible to foodborne illness, prevention is key. Health professionals and public health agencies recommend several food safety practices:
- Avoid high-risk foods: These include unpasteurized dairy, raw or undercooked eggs, deli meats (unless heated), raw sprouts, and soft cheeses.
- Cook foods to safe temperatures: Use a food thermometer to ensure meat, poultry, and seafood are fully cooked.
- Practice proper hygiene: Wash hands, utensils, and surfaces regularly.
- Store food properly: Refrigerate perishables promptly and avoid foods that have been left out.
- Stay informed: Keep up with recalls and food safety alerts, especially if you’re part of a high-risk group.
Final Note
Foodborne illness is not a one-size-fits-all threat. While a healthy adult might shrug off a mild bout of food poisoning, someone in a vulnerable group could face life-threatening complications. Understanding who is at risk, and why, helps shape better personal habits, informed healthcare guidance, and public health policies.
By identifying susceptibility factors and promoting protective practices, we can help reduce the burden of foodborne disease and protect those most at risk. After all, a safe food system is one that keeps everyone safe, not just the strongest among us.
