A decrease attention span is not likely a result of regular activity. In fact, it would be the opposite way around.
Crushing a can.
Melting an ice cube.
Boiling water.
Mixing sand and water.
Breaking a glass.
Dissolving sugar and water.
Shredding paper.
Chopping wood.
Answer: There would many terms such for communicable disease such as infectious disease, transmissible disease, and/or contagious disease.
* Hopefully this helps:)