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in 2008 archaeologists uncovered two 9
thousand year old skeletons there's no
definitive way of knowing what killed
these ancient people but we do know
their bones were infected by an
all-too-familiar bacterium the ancient
Greeks knew it's consumptive effects as
thisis the Incans called it Chucky unque
and the English called it tuberculosis
today tuberculosis or TB is still one of
the world's biggest infectious killers
causing more deaths than malaria or even
HIV and AIDS but what exactly is this
disease and how is this pathogen
persisted for so long typically TB
bacteria called Mycobacterium
tuberculosis are airborne they travel
into our Airways and infect our lungs
here immune cells called macrophages
rush to the infection site attempting to
absorb and break down the bacterial
invaders in many cases this response is
enough to remove the bacteria but in
individuals with other medical
conditions ranging from malnutrition and
HIV to diabetes and pregnancy the immune
response may not be strong enough to
destroy the intruder if so Mycobacterium
tuberculosis will reproduce inside those
macrophages and form colonies in the
surrounding lung tissue as they infect
more cells the bacteria employs cell
degrading enzymes that destroy the
infected tissue triggering chest pain
and causing patients to COFF up blood
the damage to the lungs leads to oxygen
deprivation this begins a flood of
hormonal changes including a decrease in
appetite and iron production from here
microbes can spread to the skeletal
system causing back pain and difficulty
moving to the kidneys and intestines
causing abdominal pain and to the brain
causing headaches and even impaired
consciousness these symptoms produce the
classic image of TB weight loss a
hacking bloody cough and
ashin skin this ghostly appearance
earned TB the title of the white plague
in Victorian era England during this
period tuberculosis was considered a
romantic disease because it tended to
affect poverty-stricken artists and
poets those with weaker immune systems
tb's outward symptoms even helped fuel
the popular myth of vampirism in spite
of or perhaps because of these less than
scientific concerns this period also
marked the first strides toward curing
TB in 1882 the German physician robear
kok identified the diseases bacterial
origins 13 years later physicist Vilhelm
Franken discovered the x-ray enabling
physicians to diagnose and track its
progression through the body these
techniques allowed researchers to
develop reliable and effective vaccines
first for smallpox and again in 1921
when scientists developed the BCG
vaccine to battle TB these developments
laid the groundwork for the modern field
of antibiotics currently home to our
most effective TB treatments but
antibiotics fail to address a major
diagnostic complication about 90% of
people infected with TB don't show any
symptoms in these latent infections the
TB bacterium may be dormant only
activating when someone's immune system
is too weak to mount a defense this
makes t be much harder to diagnose and
even when properly identified
traditional treatments can take up to
nine months requiring multiple drugs and
a high potential for side effects this
discourages people from finishing the
full course and partial treatment
enables bacteria to develop resistance
to these drugs today the disease is
still prevalent in 30 countries most of
which face other health crises that
exacerbate TB and trigger latent cases
were still accessing treatment can be
difficult in many of these countries and
the stigma towards TB can discourage
people from getting the help they need
health experts agree we need to develop
better Diagnostics faster-acting
antibiotics and more effective vaccines
researchers have already developed a
urine test that yields results in 12
hours as well as a new oral treatment
that could cut treatment time by 75%
hopefully with advancements like these
we'll finally be able to make TB
exclusively a thing of the past
how do vaccines work and how do they
help eradicate diseases
check out this lesson to learn about the
science behind vaccines or this lesson
about how we conquered the deadly
smallpox virus
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