2.1 | Urban Evolution and Disease
Urbanization has been accompanied by disease as it causes disruptions in
the natural environment and create congenial conditions in the built-up
environment for the spread of communicable diseases. Pandemics have been
characterized by three principal modes of transmission in cities:
airborne, waterborne, and vector-borne. Airborne transmission is
conditioned by deteriorating air quality, vehicular congestion,
haphazard construction of buildings, non-separation of patients with
infectious diseases in hospitals, and lack of civic services and
healthcare facilities to the public. Waterborne transmission depends on
improper disposal of waste and lack of potable drinking water, drainage,
and sewerage in municipalities. Vector borne diseases are transmitted to
humans and animals by blood-sucking parasites such as mosquitoes and
fleas. Table 2 depicts the main diseases transmitted by various modes.
Table 2: Diseases: Mode of Transmission