Which of the following conditions is not considered communicable?

Diabetes is classified as a non-communicable disease, which means that it cannot be transmitted from one person to another. This condition is typically related to genetic, lifestyle, and environmental factors rather than an infectious agent. In contrast, conditions like diphtheria, smallpox, and typhoid fever are all caused by specific pathogens—bacteria or viruses—that can be spread between individuals through various means, including direct contact, respiratory droplets, or contaminated food and water. Understanding the distinction between communicable and non-communicable diseases is crucial for prevention and management strategies in healthcare.