State any two conditions essential for being free of disease.

Are having a balanced diet and maintaining personal and public hygiene the same or different? Why?

Under which of the following conditions are you most likely to fall sick?
$(a)$ When you are taking examinations.
$(b)$ When you have travelled by bus and train for two days.
$(c)$ When your friend is suffering from measles.
Why?

What are the different means by which infectious diseases are spread?

What are the immunisation programmes available at the nearest health centre in your locality? Which of these diseases are the major health problems in your area?

In which of the following cases do you think the long-term effects on your health are likely to be most unpleasant?
$A)$ If you get jaundice,
$B)$ If you get lice,
$C)$ If you get acne.
Why?