Brief Answer:
Follow the Advises..

Detailed Answer:
Hello XXXXXXX Welcome to HCM,
I've gone through your query and understand your concern for your father,

Sign and symptoms of Chikungunya are quite similar to that of other tropical viral illness (eg. Dengue etc.), and as per your description it seems like he's(your father) in the capillary leak phase..

Don't worry, it'll get passed, but few necessary investigations followed by a proper clinical examination needs to done..please get Repeat CBC, LFT, KFT done and let him get examined thoroughly by an Internal Medicine specialist (after clinical examination and lab investigations, if there's no other underlying causes detected then it'll be subsided within a few days of symptomatic and supportive therapy only i.e. continuous mobilization, limb physiotherapy, a short course of diuretics etc.)..

If there's any breathing difficulty then there's a need to get a Chest X-ray (PA view) to be done also..

Keep the limbs elevated while sleeping(one/two pillow underneath) and do not let him sit down with legs hanging downwards for the time being..make sure he moves around, being physically active is very important now..

Good to know that sugar and BP is normal..

Let me know if there's any further queries..

Take Care
Kind Regards

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