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Health and Disease Control - Mosquito-borne Diseases: Malaria and Dengue

Grade 5CBSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

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Malaria is caused by a protozoan parasite called Plasmodium. It is transmitted to humans through the bite of an infected female Anopheles mosquito.

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Dengue is a viral disease caused by the Dengue virus (DENVDENV). It is spread by the Aedes aegypti mosquito, which typically bites during daylight hours.

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Mosquitoes require stagnant water (H2OH_2O) to lay their eggs. Common breeding sites include flower pots, discarded tires, and water coolers.

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Malaria is characterized by recurring high fever, chills, and sweating. Dengue is often called 'breakbone fever' because of the severe muscle and joint pain it causes.

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Preventative measures include using mosquito nets, wearing long-sleeved clothes, and applying repellents containing DEETDEET or natural oils like citronella.

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Biological control involves introducing fish like Gambusia into ponds, which eat mosquito larvae, or spraying oil on H2OH_2O surfaces to block the supply of oxygen (O2O_2) to the larvae.

📐Formulae

Stagnant H2O+Mosquito Eggs→Larvae→Pupae→Adult Mosquito\text{Stagnant } H_2O + \text{Mosquito Eggs} \rightarrow \text{Larvae} \rightarrow \text{Pupae} \rightarrow \text{Adult Mosquito}

Oil Layer on H2O⇒Blocks O2 supply⇒Larvae Death\text{Oil Layer on } H_2O \Rightarrow \text{Blocks } O_2 \text{ supply} \Rightarrow \text{Larvae Death}

Female Anopheles+Plasmodium→human biteMalaria Infection\text{Female } Anopheles + Plasmodium \xrightarrow{\text{human bite}} \text{Malaria Infection}

💡Examples

Problem 1:

Why is it recommended to clean water coolers and change the H2OH_2O at least once a week?

Solution:

Cleaning prevents the accumulation of stagnant H2OH_2O.

Explanation:

The life cycle of a mosquito from egg to adult takes about 77 to 1010 days. By changing H2OH_2O every week, we break the life cycle and prevent larvae from maturing into adult mosquitoes that spread diseases like Malaria and Dengue.

Problem 2:

A patient suffers from a very high fever and severe pain in the joints. Which mosquito-borne disease is more likely: Malaria or Dengue?

Solution:

The patient is likely suffering from Dengue.

Explanation:

While both cause high fever, the 'breakbone' sensation or intense joint and muscle pain is a signature symptom of the Dengue virus (DENVDENV), whereas Malaria is more commonly associated with cycles of shivering (chills) followed by high fever.