Is it wrong to spray with insecticides to prevent the spread of various illnesses, such as malaria?

Of course we must have respect for all life, but this is a question of motive and degree. If, because of certain circumstances, there are insects that cause disease, then the motive in using sprays is a good one. Respect for life must be tempered with the necessity to ensure that the conditions in which it can flourish are met. Human life weighs heavier in the balance than that of disease carrying insects.