Infection and Allergy
Infection occurs when organism is attacked by disease causing agent, they multiply in the host body & produce toxins. Infection may remain localized or it can be spread through blood or lymphatic vessels to overall body. Infections are caused by infectious agents like virus, viroid, bacteria, prions etc. Host body fights infections by provoking immune system. Infections can be treated by medications like antibiotics, antivirals, antifungals etc.