imagine living in darkness you're in a
roof the size of a closet with your
entire family I can't see a thing but
you can hear and smell everything every
breath every sneeze every cough that
hits your face this is life in a 19th
century city there's a story of 19th
century American history which is about
progress the rise of America to becoming
a great economic power but there's a
pretty grim underbelly to that story and
that is a really shocking rate of death
to infectious diseases America in the
1700 is to a large extent a country of
Hamlet's and villages and small towers
with a few cities which are slowly
growing come the 1800s cities like
Boston and New York are doubling and
doubling again technological innovation
was thriving
titans of business like Rockefeller and
Carnegie for growing industries at
unprecedented rates railroads were
transporting people and things faster
machines were making things more
efficiently than humans ever had in
history this was quite literally a
revolution tons of new jobs were created
but here's the thing the cities weren't
ready for all those people so places
like New York City ended up packing
these newcomers and to cheap apartments
or tenements they were small and rarely
had windows so there was no light or
ventilation houses are overcrowded
they're working in factories that
breathing on one another that
contaminating one another with their
germs and also with VCS that's right
feces that's because there weren't
proper sanitation or sewer systems or
clean water supplies very rapidly people
are starting to drink water which
contains feces from their neighbors
through a number of diseases that
claimed a lot of lives
the most serious were respiratory
illnesses and the biggest killer of all
was tuberculosis tuberculosis killed one
in seven in the United States in Europe
at this point people came to suspect
that their living conditions influenced
their health they began to argue if you
want to combat diseases you've simply
got to clean up the slum areas in fact
in New York in the 1830s they have
people sweep the streets and this has
the Helle beam dump the decades and
they're amazed to find that underneath
all the muck and the film and the
decomposing animal bodies the rattling
cobblestones
they're all doing this because they
believe in my asthma's these gases that
rise up from decomposing matter which
they believe somehow cause sickness but
the efforts of clean cities got a major
push in the late 19th century when
doctors and scientists were able to
prove that diseases were not caused by
my asthma's but by germs one of those
doctors was Robert Koch Robert Koch was
a German general practitioner who in his
spare time when not treating patients
devoted endless hours to investigating
disease under the microscope he
discovered that specific germs caused
specific diseases but he's probably best
known for his work in tuberculosis
he discovered the germ responsible and
found that it's transmitted through the
air now that people realize what causes
infectious disease they have every
incentive making sure that people have
clean water when you wash your hands you
wash away many of the disease-carrying
smudges you may have picked up and they
have sewage pipes to take away the
effluence
Wallace leads to is large-scale civil
engineering projects across America due
to the improved access to clean water in
the first few decades of the 20th
century US cities saw an estimated 50%
drop in mortalities laws were also
passed to reform housing in the cities
to ensure residents had sufficient light
and proper ventilation in their homes in
less than 20 years the death rate from
tuberculosis plummeted from one out of
every seven to more like one in 1,000 in
the United States Robert Koch even got a
Nobel Prize for the impact of his
tuberculosis research life generally was
getting better and better for Americans
knowing that germs cause disease was a
significant component of that
you
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