Answer:
Early theories stated that malaria was caused by "bad air" from marshes and marshlands. People started following the idea of Louis Pasteur, that most infectious diseases are caused by germs. This still wasn't the reason though. Many people searched for the infectious agent that could be on the soil or in the marshlands. People would have probably created a whole different medicine that would have treated bacteria that was in the soil, even though most bacteria in the soil is good. They would have probably done some cleaning of marshes and wetlands.
Explanation:
