The spread of disease in urban tenements in the early 1900s was mostly caused by overcrowding.
The smallpox epidemic rocked the city back then. Since smallpox is easily spread through contact, congested environments make for ideal smallpox breeding grounds ( they still has not developed a smallpox vaccine back then)
In the early 1900s, disease spread primarily and directly in city tenements due to overcrowding.
What is crowdedness?
Overcrowding is a phrase used to describe how crowded an area is. Here, the situation is defined as when many individuals are discovered residing in an area that is insufficient for all of them.
Keep in mind that illness propagation in cities was mostly and directly caused by overcrowding.
Learn more about crowdedness here:
https://brainly.com/question/24220915
#SPJ4
