What is the estimate for the number of callers in the human body ?

Calculating the number of cells in the human body is tricky. Part of the problem is that using different metrics gets you very different outcomes. Guessing based on volume gets you an estimate of 15 trillion cells; estimate by weight and you end up with 70 trillion. Hope this helps! 

I think the answer will be the misuse of medication.

The misuse of medication has caused some re-emergence of diseases.

I hope this helps!