Why do we have bad bacteria in our body

Explanation is given below.

Explanation:

In human body there are both good and bad bacteria present in a balance percentage of 85% of good bacteria and 15% of bad bacteria. The presence of good bacteria helps the body to perform several tasks efficiently. The bad bacteria can enters the body through mouth by eating and drinking, nose by inhaling in bad air and by intake of drugs or any unsuitable medicines directly to the blood by injections. If the percentage of the bad bacteria goes beyond to the balanced state then it can cause many diseases caused by bacteria and may cause death of the person.

On the other hand the presence of the bad bacteria that is normally balanced by a healthy body itself helps the person to keep his/her immune system strong and deal with various bacterial attacks to the body.

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