Tsetse-fly is a vector of a disease known as

Step 1: Analyze the question The question asks which disease is spread by the tsetse fly. A vector is an organism that carries a pathogen from one host to another.

Step 2: Explain the concept Different disease vectors transmit different diseases:

• Female Anopheles mosquito: malaria
• Culex mosquito: elephantiasis (filariasis)
• Housefly: cholera, dysentery, typhoid (through contaminated food and water)
• Tsetse fly (Glossina species): African trypanosomiasis, also called sleeping sickness. The pathogen is a protozoan, Trypanosoma brucei gambiense or T. b. rhodesiense.

Step 3: Work through the options

• A. Cholera: caused by the bacterium Vibrio cholerae, spread through contaminated water and food. Not the tsetse fly.
• B. Dysentery: caused by bacteria or amoebae, spread through contaminated food and water. Not the tsetse fly.
• C. Elephantiasis: caused by filarial worms and spread by mosquitoes. Not the tsetse fly.
• D. Malaria: caused by Plasmodium and spread by the female Anopheles mosquito. Not the tsetse fly.
• E. Trypanosomiasis: sleeping sickness, spread by the bite of the tsetse fly. This is correct.

Step 4: Answer The correct answer is E. trypanosomiasis.

Tip: Link the names: Tsetse → Trypanosoma (both start with "T"). Also remember Anopheles → Malaria, and Culex → Elephantiasis. Match each vector to its disease before the exam.