Typhoid : Bacteria
Explanation
Water-borne diseases are caused by pathogenic microorganisms that are transmitted in water. These pathogens can be bacteria, viruses, protozoa, or intestinal parasites. Understanding the specific causative agent for each disease is crucial for classification and treatment.
Option Analysis:
- Cholera : Virus is Incorrect: Cholera is an acute diarrhoeal infection caused by the ingestion of food or water contaminated with the bacterium Vibrio cholerae. It is not a viral disease.
- Typhoid : Bacteria is Correct: Typhoid fever is a life-threatening infection caused by the bacterium Salmonella Typhi. It is typically spread through contaminated food or water.
- Dysentery : Fungi is Incorrect: Dysentery is an intestinal inflammation, primarily of the colon. It is generally caused by bacteria (Shigella species causing Bacillary dysentery) or protozoa (Entamoeba histolytica causing Amoebic dysentery). It is not typically caused by fungi.
- Polio : Bacteria is Incorrect: Polio (Poliomyelitis) is a highly infectious disease caused by the poliovirus. It is transmitted through the fecal-oral route (contaminated water or food). It is not a bacterial disease.
Key Takeaway: Typhoid and Cholera are classic examples of bacterial water-borne diseases, whereas Polio and Hepatitis A are viral water-borne diseases.