The interspersion of various degrees of chlorosis with the normal green colour of the leaf is called

Influenza is caused by

It is said that diseases are spreading faster due to globalization and increased movement of people. Justify the statement taking the example of the $H_5N_1$ virus.

'Chicken pox' is caused by

Which of the following causes respiratory distress without affecting the lungs?

Which of the following pairs of diseases are both caused by viruses?