Final answer:
EHEC is indeed a significant cause of diarrhea in developing countries and can be fatal for young children due to complications such as HUS. Diagnosis typically involves culture and PCR, while preventive hygiene measures can help reduce risks.
Step-by-step explanation:
The statement that enterohemorrhagic E. coli (EHEC) is a major cause of diarrhea in developing countries and may result in the death of small children is true. EHEC infections can range from mild diarrhea to life-threatening conditions, including severe bloody diarrhea and complications such as hemolytic uremic syndrome (HUS). Early diagnosis and appropriate treatment are critical in managing EHEC infections, and diagnosis is often achieved through culture and Polymerase Chain Reaction (PCR). Preventive measures such as maintaining proper hygiene, cooking meats thoroughly, and ensuring safe drinking water are key to reducing the risk of infection.