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In 1987, tens of thousands of people gathered in Saudi Arabia for the annual Hajj pilgrimage.
But what started out as a celebration led to a health crisis:
just a few days after the pilgrimage, more than 2,000 cases of meningitis
broke out spreading across Saudi Arabia and the rest of the world.
The outbreak was so fierce that it was believed to have sparked a wave of deadly meningitis
epidemics that ultimately infected tens of thousands of people worldwide.
Meningitis is the inflammation of the meninges, three tissue layers responsible
for protecting the brain and spinal cord. What makes meningitis so dangerous compared
to other diseases is the sheer speed with which it invades a person's body.
In the worst cases, it causes death within a day. Fortunately, that's rare
for patients who receive early medical treatment.
The disease primarily comes in three forms:
fungal, viral, and bacterial-- the last being the most deadly by far,
and what we'll focus on.
People usually contract bacterial meningitis by breathing in tiny particles
of mucus and saliva that spray into the air when an infected person sneezes or coughs.
It can also be transmitted through kissing, or sharing
cigarettes, toothbrushes or utensils. Some people can be infected and carry the
disease without showing symptoms or getting sick, which helps the disease
spread quickly to others.
Once the bacteria enter the nose, mouth, and
throat, they cross the surrounding membranes and enter the bloodstream.
From there, bacteria have rapid access to the body's tissues--including a membrane
called the blood-brain barrier. This is made of a tight mesh of cells which
separate blood vessels from the brain, and block everything except for a specific
set of particles, including water molecules and some gasses. But in ways
that scientists are still trying to understand, meningitis bacteria can trick
the barrier into letting them through.
Inside the brain, the bacteria swiftly infect the meninges.
This triggers inflammation as the body's immune response
kicks into overdrive, bringing on fever and intense headaches. As swelling in the
meninges worsens, the neck begins to stiffen. Swelling in the brain disrupts its
normal function--causing symptoms like hearing loss and extreme
light sensitivity. As pressure increases in the cranium, it may also make the
person confused--one of the hallmarks of the disease.
A few hours in, the rapidly multiplying bacteria start to release toxins,
leading to septicemia,
also known as blood poisoning. This breaks down blood vessels,
letting blood seep out and form what starts out looking like a rash, and
evolves into big discoloured blots beneath the skin. At the same time, those toxins
burn through oxygen in the blood, reducing the amount that gets to major organs like
the lungs and kidneys. That increases the chance of organ shut down--and alongside
spreading septicemia, threatens death.
That all sounds scary, but doctors are so
good at treating meningitis that a visit to the hospital can drastically reduce an
adult's risk of dying from it. The longer it's left untreated, though, the more
likely it will lead to lasting damage. If declining oxygen levels cause cell
death in extreme parts of the body--like fingers, toes, arms and legs--the risk
of amputation goes up. And if bacterial toxins accumulate in the brain and trigger
cell death, meningitis could also cause long-term brain damage and memory loss.
So fast treatment, or better yet, prevention, is critical.
That's why most countries have vaccines that defend
against the disease in its deadliest forms.
Those are usually given to the people who are most at risk--like young children,
people with weak immune systems, or people who gather in large groups where an
outbreak of meningitis could potentially happen.
In addition to those gatherings,
meningitis is most common in a region called the meningitis belt that stretches
across Africa, though cases do happen all over the world. If you're concerned that
you or someone you know may have meningitis, get to the doctor as soon as
possible; quick action could save your life.