Question

why do we fall ill??

Answer 1

because of unhealthy food which we eat and also because of the changing temperature

Answer 2

Infectious diseases are caused by pathogens such as bacteria, viruses, fungi and parasites. These pathogens can enter the body through the air we breathe, the food and drink we consume or through openings in the skin, such as cuts. As an example, think of a person who has a cold.
Hope it helps☺☺