Which of the following is a pathogenic strain of E. coli?

The identification of pathogenic strains of E. coli is crucial in understanding foodborne illnesses and gastroenteritis. Enterohemorrhagic E. coli (EHEC) is a well-known pathogenic strain that can cause severe foodborne illness characterized by bloody diarrhea and can lead to serious complications such as hemolytic uremic syndrome. This strain is often linked to undercooked beef and contaminated produce, emphasizing its public health significance.

Enteroinvasive E. coli (EIEC) is another pathogenic strain, similar to Shigella, that invades the intestinal mucosa and can cause dysentery-like symptoms. EIEC is capable of causing disease through its ability to invade and replicate within epithelial cells, leading to inflammation and diarrhea.

Both EHEC and EIEC are recognized for their pathogenicity and association with gastrointestinal disease, affirming that they are harmful to humans. This makes the choice that includes both EHEC and EIEC as pathogenic strains of E. coli the most comprehensive and accurate. Recognizing the pathogenic potential of these strains is essential in microbiology, particularly in the context of infection control and food safety.