Explain any three preventive measures to control microbial infections.

Explanation

(i) Air-borne diseases like pneumonia, influenza, etc. can be prevented by avoiding overcrowding and unhygienic conditions.
(ii) Water-borne diseases like cholera, typhoid, etc. can be prevented by boiling water or treatment of water.
(iii) Contagious diseases like measles, chicken pox, etc. can be prevented by isolation of infected persons.
(iv) Vector-borne diseases like malaria, dengue, etc. can be prevented by killing the vectors by spraying insecticides.