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Recently there has been[br]a lot of talk about measles.

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What does measles actually do,[br]and should you vaccinate against it?

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Or is this just hysteria?

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Measles is a virus:

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a hull of proteins, RNA,

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plus some more proteins for reproduction.

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It cannot reproduce by itself;[br]it needs a host cell to do so.

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To understand measles, we have to[br]understand the immune system.

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You might already have seen

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the visual system we developed[br]to help here.

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Now, let’s focus on the parts of[br]the immune system relevant to measles.

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The measles virus enters humans[br]through the nose, mouth, or eyes.

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The measles infection starts in the lungs.

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Measles is especially good at infecting[br]the body’s first line of defence:

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macrophages, powerful guard cells[br]that protect the lungs from intruders.

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They enter a cell and take it over.

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The virus reprograms the cell and

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transforms it into a dangerous[br]virus production center.

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Once a cell is filled with viruses,

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they leave the crippled cell[br]and begin the cycle over again.

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But the immune system has[br]powerful weapons against virus infections:

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natural killer cells.

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These cells basically patrol the body[br]and check other cells for infections.

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If they find an infected cell,[br]they order it to commit suicide.

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This is so effective that for[br]the first 10 days or so,

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you will not even notice that[br]you’re infected with measles.

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And now, the reason why measles[br]is so powerful.

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After a period of fighting and dying,

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macrophages alert the brain of the[br]immune system:

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the dendritic cells.

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The job of the dendritic cells is[br]to collect samples of intruders,

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travel to the lymph nodes,

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and then activate the heavy weapons

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that eradicate the infection very fast[br]in a team effort.

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But the measles virus uses[br]a dreadful tactic.

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It infects the dendritic cells

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and uses them as a Trojan horse[br]to enter deeper into the body.

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The infected cells travel to the next [br]lymph node

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to alert other immune cells.

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Once it arrives,

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the measles virus spreads around the[br]virgin T and B cells

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and infects them.

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It attacks the very system that[br]evolved to fight it.

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Now, things happen very fast.

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The lymph system spreads the virus[br]everywhere

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and it enters the bloodstream,

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infecting cells while traveling.

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Measles infects organs like

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the spleen, the liver, the intestines,[br]and, most importantly, the lungs.

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The symptoms range from

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a very high fever, headache, sickness,[br]bronchitis, and, of course, a rash.

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In the lungs, the immune system was[br]doing pretty okay.

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But now, millions of viruses[br]attack a second time

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and kill countless cells, wiping out[br]the defense systems.

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In this phase, you start coughing out[br]millions of measles viruses.

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Measles is so contagious at this stage,

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that if you meet someone[br]who isn’t vaccinated,

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there’s about a 90% chance[br]you’ll infect them.

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Without the protective army in the lungs,[br]other bacteria or viruses that

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would usually not stand a chance can[br]now enter the lungs and develop into

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harmful parallel infections that[br]can cause pneumonia,

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the most common way to[br]die from measles.

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Your body’s immune system is now[br]seriously wounded.

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Various protective systems are hurt[br]and disrupted.

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The virus spreads everywhere, infecting[br]the skin all over the body.

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The typical measles rash now[br]becomes visible.

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And in some cases, the measles virus

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reaches the brain and causes[br]a brain infection.

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If it does so, the chances of dying[br]are between 20 to 40 percent,

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and there may be long-term damage.

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But your body is far from giving[br]up at this stage,

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and it fights back agressively.

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Some dendritic cells survive[br]long enough to activate

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the anti-virus forces of the body.

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Plasma cells in the lymph nodes[br]start producing billions of antibodies,

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tiny proteins that mark infected cells[br]for destruction

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or clump the virus together.

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Killer T cells flood the body[br]and kill infected cells left and right.

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After 2 to 3 weeks, the body usually gets

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the upper hand and overwhelms[br]the infection.

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But the immune system is now[br]seriously weakened,

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and may take weeks or months to recover,

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leaving the body vulnerable[br]to other diseases.

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But, if you make it, you are now immune:

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the immune system remembers[br]the virus forever.

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Measles is no joke.

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Although 84% of all humans are[br]vaccinated against measles,

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122,000 people died because[br]of the infection in 2014.

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Some people cannot get vaccinations,

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either because they’re too young,[br]because of chemotherapy or HIV,

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or because they’re allergic[br]to the vaccine.

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They need the rest of us to[br]stop the disease for them.

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The measles vaccination is[br]safe, cheap, and available.

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There are no benifits from having[br]measles at all.

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You don’t strengthen your immune[br]system and it’s not more natural.

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Most people who don’t vaccinate[br]only want the best for their children,

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which is honorable.

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But if you ask yourself,

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“Am I putting the life of my child[br]and other children at risk by

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not vaccinating against measles?”

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The sad answer is yes. Yes, you are.

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Let’s not play the blame game, though.

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Let’s work together and[br]eradicate this virus.

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Together, we can get rid of these[br]dreadful monsters and

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consign them to their rightful place:[br]the history books.