Dengue virus causes high fever, rashes and reduces the number of a particular type of blood cells. Those blood cells are
- A.Monocytes
- B.Platelets
- C.Eosinophils
- D.Neutrophils
Correct answer
Explanation
The correct answer is B, Platelets. Dengue is known for lowering the platelet count, which can lead to bleeding in severe cases.
Dengue is a viral disease spread by the bite of the Aedes mosquito, mainly Aedes aegypti, which breeds in clean, stagnant water and bites during the day. Its symptoms include high fever, severe headache, pain behind the eyes, joint and muscle pain ("breakbone fever") and skin rashes. Platelets, also called thrombocytes, are cell fragments that help blood to clot. A normal count is about 1.5 to 4.5 lakh per microlitre; in dengue it can fall sharply, causing bleeding from the gums or nose.
A is wrong because monocytes are white blood cells that become macrophages and eat germs; their fall is not the sign of dengue.
C is wrong because eosinophils are white blood cells linked with allergies and worm infections.
D is wrong because neutrophils are the most common white blood cells and fight bacterial infections first.
Exam tip: dengue, chikungunya and Zika are spread by Aedes; malaria by the female Anopheles mosquito.
Practice Questions
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- B.2 : 1
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- D.8 : 1
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- B.Dengue
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