Yes. It was called Miasma Theory. This was believed from Roman times right up until the 19th century. The invention of the microscope lead to Germ Theory. In pre-industrial times it was thought that bad smells caused disease because they noticed disease would often occur around rotting flesh.

Microorganisms are associated with disease because they are the common cause of disease. For centuries it was believed that bad smells or miasma was the cause of disease. This attitude later changed as microorganisms were discovered and proved to be the actual source of disease.

Blue Miasma was created in 2006.

It proposed that cholera was caused/spread by bad vapours in the air.