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  • We all know we should donate blood, but probably don't as much as we

  • should. Every year almost 5 million Americans need blood transfusions and

  • would likely die without them. Approximately 32,000 pints of blood are

  • used each day in the United States for people who lose blood during operations

  • or from traumatic injuries. Others need blood transfusions because of ongoing

  • illness like sickle-cell anemia where they all need transfusions throughout

  • their lives. The network of blood donation and transfusion in any country

  • is a hugely vital part of keeping sick or injured people alive and well. This

  • wouldn't be so complicated if we all had the same type of blood, but we don't. And

  • some of us have such rare blood types that any injury, any procedure, or any

  • accident can be life-threatening. Imagine your blood was so rare and so

  • unique that should you get hurt, almost no one else in the worlds donated blood

  • would be able to save you. So rare and so valuable that your identity needs to be

  • concealed to keep a never-ending stream of requests for it at bay. So rare that

  • scientists would do almost anything to get their hands on a pint of it to study.

  • For the people who have the rarest blood type in the world, Rh null this is their

  • reality. It's the world's most dangerous blood type to have because only 43

  • people in the world are discovered to have it. Meaning if you get hurt,

  • basically no one else's blood would be compatible with yours. Injuries that

  • would be serious but treatable for everyone else would probably be fatal

  • for you. Most of us have probably heard of the usual blood type system, or even

  • know our own blood type. O+, AB-, A+, O-. This

  • classification determines who we can donate blood to or receive it from. There

  • are a total of 33 different classification systems recognized but

  • most people only need to worry about the two most common ones, the ABO and Rh

  • systems. The ABO system classifies blood based on the presence of antigens,

  • antigen A and antigen B. You can have one or the other, both, or neither. Antigens are

  • glycoprotein markers embedded in the cell membrane and help your immune

  • system to distinguish between your body's own cells and foreign cells like

  • viruses or bacteria. In an A blood type the A antigen is found on the blood cell

  • itself and an A or anti-B antibody is found in the blood serum. In a B blood

  • type a B antigen is found on the blood cell and a B or anti-A antibody is

  • found in the serum. Blood type AB has both A and B antigens on the blood cells

  • and neither of the corresponding antibodies against them in the serum. And

  • blood type O has neither antigen on the cells but has antibodies A and B in the

  • serum. When blood is donated, the red blood cells are separated from the

  • plasma where the antibodies are located through a process called blood

  • fractionation. This ensures that only the red blood cells get donated and not

  • their corresponding antibodies since that would cause an adverse reaction in

  • the recipient. Your immune system will produce antibodies against any blood

  • antigens you don't have in your own blood. Therefore a person with type A

  • blood that receives B blood would have an ABO incompatibility reaction. The

  • anti-B antibodies present in the patient's blood would agglutinate

  • with the B antigens on the donated red blood cells making the blood cells clump

  • together and block small blood vessels. The immune system would then attack the

  • new blood cells and destroy them. It's rare for this to happen but if it does

  • it is serious and potentially fatal. Transfusion is considered safe as long

  • as the serum of the recipient does not contain antibodies for the blood cell

  • antigens of the donor. So this is why if you have type AB blood you're a

  • universal recipient - you don't have either of the antibodies that would

  • attack A or B donor blood. However this also means you can only donate blood to

  • other people who have A B blood. If you have type O blood you're universal donor.

  • You can give your blood to a A B or O without triggering their

  • immune system. But this is also why people with O blood can only receive

  • Type O blood. However there are other antigens that

  • need to be accounted for beyond the ones and the ABO system before donating or

  • receiving blood safely. This is where the rhesus system comes in. The rhesus, or Rh

  • system, is the second most significant blood group system. These are the most

  • important antigens with the most significant one being the D antigen.

  • Although there are lots of other Rh antigens RH-D is the most significant

  • because it's the most likely of the Rh antigens to produce an immune response.

  • Depending on whether the RH-D antigen is present, each blood type is assigned a

  • positive or negative symbol. People who are Rh-D negative can only receive Rh-D negative

  • blood. But people who are Rh D+ can receive either Rh D positive or Rh D negative

  • blood. The negative blood types, A negative, B negative, AB negative, and O

  • negative are more rare than their positive counterparts. And while the D

  • antigen is the most important one in the Rh system there are a total of 60 other

  • Rh antigens making it the largest of any of the blood classifications. And while

  • these eight blood types are the most common way of describing our blood, each

  • of these eight types can be subdivided much further. There are millions of

  • varieties, each classified according to the exact antigens that coat the surface

  • of our red blood cells. To know your exact blood type you'd have to write it

  • out antigen by antigen. Luckily for most of us many of the

  • antigens we have don't affect our ability to receive or donate blood

  • because pretty much everyone else also has them. For example more than 99.9%

  • of people carry the antigen called Vel. So for most of us donating

  • blood to one another we wouldn't need to worry about this antigen as it wouldn't

  • trigger an immune response. But for every 5,000 people there's one person

  • who does lack the Vel antigen who shouldn't receive blood from the other

  • 4,999. Their immune system recognizes the

  • Vel antigen as foreign and if given Vel positive blood they could have

  • kidney failure and possibly die. But doctors do screen for as many of these

  • variants as possible to make sure to find the best match for a blood

  • transfusion. But sometimes this best match isn't really possible and this is

  • why the rarer your blood the harder things get. The world's rarest blood type,

  • Rh-null is called Rh-null because it has none of the 61 antigens present in the

  • Rh blood system we previously discussed. It is rare enough to have a few of the

  • antigens in the Rh system missing from your blood but the chances of missing

  • them all are astronomically small. Doctors call it the golden blood because

  • for anyone who has any type of rare Rh blood type, missing a few antigens here

  • or there, the Rh-null blood can be accepted where other more typical blood

  • types could not be. It has enormous life saving capabilities but for those who

  • have it it can be a curse. Most of us likely take for granted that if we get

  • hurt the nearest hospital will be able to sort us out. But if you're one of the

  • few with Rh-null blood life is inherently more dangerous. You can't

  • receive blood from anyone else except the 42 other people that exist who have

  • been found to have the same blood type. And of the people known to have it only

  • a handful of them are active donors and they're spread across the world. And the

  • logistics of shipping blood around the world are stupidly complicated.

  • Bureaucracy and paperwork can hold things up at the borders, which can

  • create a myriad of issues. Fresh blood has a shelf life of four weeks and it

  • has to be stored at four degrees Celsius, which is challenging during

  • transportation, especially to remote areas. This means that any holdup at

  • customs can render the blood unusable. And some countries have very restrictive

  • rules in regards to importing blood. The UAE for example won't accept any blood

  • into the country that isn't from the Gulf states. These types of logistics and

  • bureaucracy make it very hard for someone with rare blood to get a

  • transfusion, especially in a sudden emergency when they need the blood fast.

  • For one Swiss man with Rh-null blood, this meant as a child, he couldn't go to

  • summer camp or do outdoor sports because his parents feared he could get an injury

  • with no ability to get a blood transfusion. As an adult he can't travel

  • to countries without modern hospitals. The only realistic way he can navigate

  • this danger is to continuously donate blood to himself,

  • meaning twice a year he donates blood to keep on reserve in case he ever needs it.

  • And he can't really donate much more than that because Rh-null blood also comes

  • with some adverse effects. The Rh antigens that most of us have are

  • thought to play a role in maintaining the integrity of the red blood cell

  • membrane. Red blood cells which lack Rh antigens have an abnormal shape and an

  • increased osmotic fragility. This means that red blood cells break down quicker

  • than they should resulting in a hemolytic anemia. This can lead to

  • fatigue, shortness of breath, and jaundice and thus makes frequent blood donation

  • impossible. And because only a handful of people with this rare blood ever donate

  • it, this places a large burden on those who do when someone else needs this type

  • of blood. Because Rh-null blood can be donated to anyone with a rare

  • combination of Rh negatives in their blood type, every once in a while they

  • may get an urgent call to donate. The Swiss man we mentioned before once had a

  • call that a newborn baby was in dire need of his type of blood. To save the

  • baby's life he would need to make his way to the donation center. This meant

  • taking a taxi to Geneva and taking time off of work, none of which is allowed to

  • be reimbursed due to the blood donation laws in some parts of Europe. He was able

  • to help in this instance, but quickly realized that the cost and burden of

  • donating his valuable blood would ultimately fall on him. Anyone with this

  • rare type of blood is given the gift of being able to help someone at a time of

  • need, an ability to help where no one else can. It probably feels pretty

  • amazing to know you've played a part in saving someone's life. But this also

  • comes with the unfortunate burden of being, in a sense, on call for your entire

  • life, should the need for your blood arise. This poses an interesting ethical

  • question. It's up to you to donate blood at a moment's notice, whether you're in a

  • client meeting, at your own wedding, or on vacation. At what point does your moral

  • obligation to help someone else in need begin and end? But for every person who was

  • otherwise doomed without this donated blood, the importance of it obviously

  • can't be overstated. And this serves as a reminder that hospitals around the world

  • rely on the good deed of blood donation to save lives, whether your blood is rare

  • or not. Since the very first blood transfusions in the 1800s

  • they have saved millions of lives and played a vital role in shaping our

  • modern world. In times of peace they've saved citizens from unfortunate

  • accidents and in times of war have saved the lives of countless wounded soldiers.

  • During World War II the American Red Cross flew almost two

  • hundred thousand pints of whole blood from the US to the Allied forces in

  • Europe. More than fifty thousand pints of blood were needed for the soldiers

  • fighting during the D-day invasion of Normandy alone. The level of coordination

  • needed for the collection and transport of this much blood is astounding, and you

  • can learn more about logistics like this in Real Engineering's new "Logistics of

  • D-Day" series available exclusively on Nebula, the streaming platform made by

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  • Crisis, BrainCraft, and our other channel Real Engineering. Nebula is a place for

  • us to make experimental and creative videos without worrying about the

  • YouTube algorithm. It has loads of original content like the logistics of

  • D-Day series, that you can watch ad-free by signing up to CuriosityStream who are

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B1 US blood blood type antigen rare donate red blood

The World's Most Dangerous Blood Type

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    joey joey posted on 2021/06/09
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