Symptoms like fever, chills, cough, headache and severe case turning of color of nail from gray to blurish occurs in :-

Answer

**Step-by-Step Solution:**

1. **Identify the Symptoms:** The symptoms mentioned in the question are fever, chills, cough, headache, and a severe case of nail color changing from gray to bluish.

2. **Understand the Symptoms:**
- Fever and chills are common indicators of infection.
- Cough can be associated with respiratory issues.
- Headache can accompany many illnesses, especially infections.
- The change in nail color from gray to bluish suggests a lack of oxygen in the blood, which is a critical symptom.

3. **Consider Possible Diseases:**
- The combination of respiratory symptoms (cough, fever, chills) and the bluish discoloration of nails points towards a respiratory infection.
- Pneumonia is a common respiratory infection that can cause these symptoms.

4. **Link Symptoms to Pneumonia:**
- In pneumonia, the lungs become inflamed and may fill with fluid, leading to difficulty in breathing and reduced oxygen levels.
- This can cause cough (due to fluid in the lungs), fever (as the body fights the infection), chills, and headaches.
- The bluish discoloration of nails (cyanosis) occurs due to insufficient oxygen in the bloodstream.

5. **Conclusion:** Based on the symptoms and their relation to pneumonia, the disease responsible for these symptoms is pneumonia.

**Final Answer:** The symptoms like fever, chills, cough, headache, and severe case turning of color of nail from gray to bluish occur in pneumonia.

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