Which of the following diseases is not caused by a virus?

Explanation

Cholera is not caused by a virus but by a bacterium called Vibrio cholerae. It is a bacterial disease that spreads mainly through contaminated water and food. The bacterium produces a toxin, known as cholera toxin, which affects the lining of the small intestine and leads to severe watery diarrhea and dehydration. Since cholera is bacterial in origin, it can be treated effectively with antibiotics and rehydration therapy. In contrast, influenza, hepatitis, and polio are viral diseases caused by different viruses: influenza by the influenza virus, hepatitis (various forms) by hepatitis viruses, and polio by poliovirus. These viruses rely on host cells for replication and cause illness by damaging host tissues or triggering immune responses. Unlike cholera, viral diseases cannot be treated with antibiotics but are managed with antiviral drugs (in some cases), supportive care, and prevention through vaccines. Thus, the difference lies in the nature of the causative agents-cholera is bacterial, while influenza, hepatitis, and polio are viral.