The vector for yellow fever is?

Step 1: Analyze the question The question asks for the vector (the organism that carries and transmits a pathogen) of yellow fever.

Step 2: Explain the concept Yellow fever is a viral disease caused by a flavivirus. It is spread to humans through the bite of an infected female mosquito. Different diseases have different vectors, which is a very common JAMB topic:

| Disease | Vector | |---|---| | Yellow fever | Aedes aegypti mosquito | | Dengue fever | Aedes mosquito | | Malaria | Female Anopheles mosquito | | Elephantiasis (filariasis) | Culex mosquito | | Sleeping sickness | Tsetse fly (Glossina) | | River blindness (onchocerciasis) | Blackfly (Simulium) |

Step 3: Work through the options

• A. Aedes mosquito: Correct. Aedes aegypti transmits the yellow fever virus.
• B. Anopheles mosquito: This transmits the malaria parasite (Plasmodium), not yellow fever.
• C. Tsetse fly: This transmits trypanosomes, which cause sleeping sickness.
• D. Blackfly: This transmits the worm Onchocerca volvulus, which causes river blindness.

Step 4: Answer The vector for yellow fever is the Aedes mosquito, which is option A.

Exam tip: Remember "Aedes = All the fevers" (yellow fever and dengue fever), and "Anopheles = Ague (malaria)". Also, Anopheles bites at night, while Aedes is typically a daytime biter with white stripes on its legs (the "tiger mosquito" look).