Enteropathogenic Escherichia coli (EPEC) is a strain of E. coli bacteria that causes diarrhoea, particularly in infants and young children. Unlike some other E. coli strains, EPEC does not produce toxins. Instead, it harms the gut by attaching tightly to the lining of the small intestine, damaging the cells and disrupting their function (Duvenage, 2022; Roussel et al., 2023). This attachment leads to a “lesion” effect that reduces the gut’s ability to absorb nutrients and fluids, resulting in watery diarrhoea (Croxen & Finlay, 2010).

EPEC infections are mainly spread through contaminated food, water, or direct contact with infected individuals. In developing countries, including parts of Africa, it is a major cause of infant diarrhoea and contributes significantly to child morbidity (Roussel et al., 2023). While healthy adults often recover without treatment, young children, the elderly, and people with weakened immune systems may experience more severe illness, including dehydration. Maintaining safe food practices, good sanitation, and access to clean water are critical to reducing EPEC infections.

✔️ What it is: A group of bacteria found in water and seafood, with some species (like Vibrio cholerae and Vibrio parahaemolyticus) causing gut infections.

✔️ Where it’s found: Common in warm coastal waters, raw or undercooked seafood (especially shellfish), and sometimes in contaminated drinking water.

✔️ How it spreads: Usually through eating contaminated food or drinking unsafe water. Rarely, through open wounds exposed to seawater.

✔️ Main symptoms: Watery diarrhoea, stomach cramps, nausea, vomiting, and dehydration. In severe cases (V. cholerae), life-threatening fluid loss can occur.

✔️ Gut health impact: Infections disrupt the gut microbiome, flush out good bacteria, and weaken digestion, making it harder to fight off other illnesses.

✔️ Who’s most at risk: People with weakened immune systems, liver disease, or low stomach acid, as well as children and the elderly.

✔️ Prevention tips: Avoid raw or undercooked seafood, ensure safe drinking water, and wash hands after handling seafood or water sources.

✔️ Testing matters: Early detection can prevent severe dehydration, restore balance in the gut, and speed up recovery.

When EPEC enters the gut, the first defence comes from the innate immune system. The gut lining recognises the bacteria through pattern-recognition receptors (like Toll-like receptors), which detect bacterial components and trigger an inflammatory response (Roussel et al., 2023). This response releases cytokines—chemical messengers that call in immune cells such as neutrophils and macrophages to fight the infection. These cells help limit bacterial growth, but the inflammation also contributes to symptoms like diarrhoea and stomach cramps.

The adaptive immune system then steps in. Specialised immune cells (T and B lymphocytes) recognise EPEC more specifically. B cells produce antibodies, including IgA, which block EPEC from attaching to intestinal cells and neutralise its virulence factors. Meanwhile, T cells support the immune response by helping clear infected cells and maintaining gut barrier integrity (Croxen & Finlay, 2010). Over time, the body develops immune memory, allowing for a faster, stronger defence if exposed again. However, in infants and young children—who are most at risk—this immune response is often weaker, making EPEC infections more dangerous (Duvenage, 2022).

Gastrointestinal Symptoms

Unhealthy levels of EPEC mainly affect the small intestine, leading to watery diarrhoea that can last for several days. Because EPEC attaches tightly to the intestinal lining and disrupts nutrient absorption, people often experience stomach cramps, nausea, vomiting, and loss of appetite (Roussel et al., 2023). In young children, this can quickly cause dehydration, which may present as dry mouth, sunken eyes, or reduced urination.

Long-Term and Severe Effects

If left untreated, especially in infants and people with weak immune systems, EPEC infections can contribute to malnutrition, weight loss, and slowed growth due to poor nutrient absorption (Duvenage, 2022). Chronic or repeated infections may also disrupt the gut microbiome, leaving the digestive system more vulnerable to future illness. In severe cases, dehydration can become life-threatening without prompt medical care (Croxen & Finlay, 2010).

In South Africa, EPEC is a noteworthy contributor to childhood diarrhoeal illness. Globally, EPEC is responsible for 30–40% of diarrhoea cases in infants, particularly among young children under two years old (Mare, 2021). Although specific national figures are limited, this global burden strongly suggests that EPEC plays a similar role in South African paediatric gut health.

Further complicating the issue, South Africa is seeing a rise in hybrid diarrhoeagenic E. coli strains—including EPEC—on everyday household surfaces like kitchen cloths and toilet areas. These hybrid strains carry multiple virulence genes and often display multidrug resistance (Rakhalaru et al., 2023). This means that even minor lapses in hygiene or sanitation can elevate the risk of EPEC infection, especially in vulnerable communities.

Why This Matters for Gut Health

Repeated or severe EPEC infections in children can impair nutrient absorption, leading to growth delays, chronic gut imbalance, and a greater likelihood of recurrent illness. Although exact data for South Africa is pending, global patterns hint at similar developmental consequences locally. Disruptions in gut health due to such infections can also undermine immune resilience and complicate recovery from other infections or illnesses.

1. Strengthening the Gut Microbiome

A healthy gut microbiome is one of the best natural defences against EPEC. Beneficial bacteria compete with pathogens for space and nutrients, helping to prevent harmful strains from attaching to the intestinal lining. Eating probiotic-rich foods (like yoghurt, kefir, kimchi, and sauerkraut) and prebiotic foods (such as garlic, onions, bananas, and legumes) encourages the growth of protective microbes (Roussel et al., 2023).

2. Maintaining Good Nutrition and Hydration

EPEC weakens the gut by reducing nutrient absorption. Supporting gut recovery means ensuring adequate hydration and a diet rich in vitamins and minerals, especially zinc, which helps repair the gut lining and supports immune responses (Croxen & Finlay, 2010). Oral rehydration solutions (ORS) are vital during diarrhoeal illness to replace lost fluids and electrolytes.

3. Hygiene and Food Safety

Because EPEC spreads through contaminated food, water, and surfaces, handwashing, safe food handling, and proper cooking are essential preventative measures. In South Africa, studies have found multidrug-resistant E. coli on fresh vegetables and household surfaces, showing that everyday hygiene is key to lowering infection risk (Duvenage, 2022).

4. Supporting Immunity

A strong immune system helps clear infections more efficiently. Adequate sleep, physical activity, and stress management all contribute to immune resilience. For high-risk groups like infants and immunocompromised individuals, regular monitoring and early testing can prevent severe outcomes.

✅ In short: strengthening the microbiome, focusing on nutrition and hydration, practising good hygiene, and supporting immunity are all crucial to protecting the gut from EPEC.