The World’s Most Dangerous Blood Type

The World’s Most Dangerous Blood Type

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to you by Curiosity Stream. Sign up today at and get free access to 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
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100 thoughts on “The World’s Most Dangerous Blood Type

  1. Hey, Nebula seems pretty cool and I would love to check it out but I'm already subscribed to curiosity stream. Is there a way for me to still get the free access to Nebula?

  2. I just watched a video on rh negative being some alien origin bullshit.
    They mentioned though that 15% of world is rh negative. And that if a rh negative woman mates with a rh positive man and the baby has rh positive blood, the baby will die. Unless they get a shot in the hospital.
    This seems like a big problem to me, does anyone know what the trueth to this is? Does this mean that for 7,% of people(15/2) they can only have a baby if they get a shot in the hospital?(is this concept true or true for a smaller percentige depending on the child getting rh positive)?

  3. This is why I have an absolute hard on for artificial blood. Less logistically demanding for the trauma management system. PFC blood substitute is especially neat for many reasons.

  4. @8:40 it's a defect.. Not a special blood type.. So literally it's rare because genetics are trying to breed it out and were desperately trying to keep it in the gene pool?

  5. I once was trying to donate blood. But the fellows were very rude, they kept asking whose blood is it, where did i get it, why the fuck was it in the bucket

  6. Rh- negative or 0- is the universal blood is comparable to anyone but it can only receive only from their own kind O-.

  7. Hello! I’m a clinical laboratory science student, and I just want to say I absolutely love this video. My favorite clinical rotation so far was the blood bank, so I really enjoyed listening to this video! You’ve made basic immunohematology more accessible to the lay population! I just wanted to mention a few clarifications and additions:

    At 2:23 A antibodies or anti-B antibodies are mentioned, along with B antibodies/anti-A antibodies. While this is correct, in the blood bank we prefer to use the terms anti-A antibodies and Anti-B antibodies, because that terminology indicates the antigen to which the antibody attaches. Often times, we leave out the term antibody, and we just say “anti-A,” for example, in the lab.

    At 4:55 a table of donor/patient compatibility comes up. This is only in the context of donating red blood cells, as donating plasma would have a different compatibility chart.

    At 5:47 the fact that most antigen-antibody reactions don’t occur often is mentioned. The video says that this is because a lot of the antigens are shared amongst the human population. While there are quite a few high incidence antigens, this isn’t the only reason we don’t really need to worry too much about our other antigens. At the beginning, the video mentions how group A people have anti-B antibodies and group B people have anti A antibodies. These antibodies naturally form in the body a few months after birth, whether or not the baby ever had an intrauterine or exchange transfusion. However, for other blood group systems, you can only develop the antibodies after you’ve been exposed to the antigen (i.e. if you’ve had a transfusion with blood containing a foreign antigen). So you can only develop anti-D antibodies if you’re Rh D negative and had a transfusion with D positive blood. You can also develop antibodies through pregnancy, but if I explain that, this would become way too long haha. And even if you are exposed, if it’s the first time, it’ll take a while for clinically significant antibodies to form. Therefore, upon first exposure, it’s unlikely that you’ll get a transfusion reaction as long as your ABO is compatible. However, subsequent exposures require more careful testing, since the following exposures will have quick antibody responses within a few days. Nonetheless, this is why it’s sometimes difficult to procure blood for people with diseases like sickle cell anemia, since they require transfusions often. At my hospital, the protocol we have for patients with sickle cell is to go ahead and provide blood that is at least antigen matched for ABO and the major Rh antigens (not just RhD).

    At 7:37 it’s stated that fresh blood has a shelf life of 4 weeks. While that is true, it depends on the anticoagulant used. Citrate phosphate dextrose (CPD) only preserves it for 21 days, but CPD with adenine preserves it for 35. There are other coagulants called additive solutions that can extend the shelf life to 42 days. While I don’t know what the other foreign hospitals use, at my hospital we usually either get blood that has CPD with adenine or an additive solution. Granted, if you freeze the blood at temperatures less than -65 degrees Celsius, it can be kept for 10 years, and they can be transported in a frozen state, though I imagine that it’s more costly to do so. Granted, freezing can damage the red blood cells (RBCs) a little bit, and with the increased osmotic fragility of Rh null RBCs, I’m not quite sure if those preservation time limits apply to that specific group.

    At 8:59 the osmotic fragility of Rh null RBCs is mentioned, and that leads to an inability to donate as often. This is true, and the symptoms the video mentions are also common symptoms of anemia. However, I believe in cases of Rh null, their anemia is compensated, meaning that they make up for their fragile RBCs by producing them more frequently than the rest of the population. This usually makes the anemia asymptomatic. Now I want to mention that I’m not completely sure about that one though, so don’t quote me on that.

    At 11:02 whole blood donation is mentioned. I just want to add that what they were able to do with all that blood in a short time is amazing, since donating whole blood is different from donating RBCs. When donating whole blood, you can’t just be ABO compatible. You have to be ABO IDENTICAL, because the whole blood also contains plasma antibodies. The fact that they were still able to save as many lives as they did with whole blood is amazing.

    Finally, I just want to end this with a plea for people to donate. I remember reading somewhere that around 35% of the U.S. population is eligible for donation, but only 5% of those eligible actually donate. So if you can, please donate! As long as there is illness and injury, there will always be a need for blood, and having a reliable stock of blood is always comforting to those of us who work in a blood bank, so I implore you all to donate the next time you see a local blood drive! And for those who already donate, it’s because of donors like you that we can provide the blood necessary to help our patients. So thank you for your contribution, and I hope you will continue to donate in the future! For those who actually read all the way to the end, thank you, and I hope you’ll find it in you to donate as well!

  8. I don't understand that law. Why couldn't they reimburse the Swiss man? At least pay for his transport fees and lunch/dinner. Why should governments give grants to Green Peace (that pretty much does nothing but whine) instead of allocating like maybe 10,000 Euros a month to ensure that these bearers of the golden blood at least don't croak early or lose their jobs?

  9. Now I know why they wanted me to sign papers to study my blood, and why they call me the royal blood. I too were told not to get hurt or cut badly. They dont even want to preform surgery even when I need it. Thank you for this video.

  10. this channel is definitely interesting but IMO it relies too heavily on stock footage. while the stock footage is relevant to what you're saying, it's still not very specific or captivating to watch, making the audio component the only big part of the video. i think real engineering also does this to an extent.

  11. Cant you be your own donor tho? like for instance freeze or otherwise preserve your own blood so in case of emergency you can just tap in your reserve?

  12. It's not painful, you get to help people AND you get some fruit juice…it's a win win situation and the closest thing you feel to doing something good to people for no reason than wanting to do good.

  13. I thought it's the Bombay type. But yeah RH null is really tricky 🙁 the patient with this kind of rare blood type can probably collect and store their own blood for emergency purposes :'(

  14. it might help more people if those who donate are given a reward.. ex: for every session of blood donation.. you are given "xx" amount of money.. it can help those who are poor and boost people to donate more.. not to mention, donating your blood once in a while is good for your health…

    did you know, That someone would be very very grateful and even pay you if you can donate your blood to their loved one who is needed.. but at the same time the same person could hold a knife or a gun to make you surrender your blood to be "donated" to their loved ones…

  15. I'm RH- and I've brown hair,brow eyes,I'm not rich with money,but rich with life.Life is diffrent with RH- blood,I heal very quick,my anti bodies fight off anything that wants trouble.But if you have kids and your partner is A- you can kill her and unborn due to blood cells being killed by white cells.Not all of us RH- are aliens or Dracula 😉

  16. I remember our previous patient who was O- and a dialysis patient, and he needed blood transfusion. Upon our rounds, we asked if they already procured blood but his wife said that they will be getting the blood from a faraway province because the donors from nearby provinces cannot do so.

  17. I wanted to donate blood, but the veins needed for it are so hard to locate in my arms the blood bank actually refused….

  18. there was so much stock footage of blood in this video… I never thought myself squeamish but it was still hard to watch

  19. Scary stuff! As if it wasn't bad enough to have a rh negative blood type, now I have anxiety over my antigens too 😣

  20. Wow, I feel very special- I have O negative with RH factor as do all three of my brothers and my mother- my three brothers come from a different father than myself and she told us we shouldn't have even survived, crazy.

  21. We should actually develop more blood transfusion alternatives and not resort automatically to transfusion in cases where volume expanders could sustain the patient while their marrow made new cells.

  22. After watching this I'm just thankful to know my blood is Rh positive, so that eliminates any anxiety I would've had about "what if I'm Rh null?". Yikes, that would suck. But this video reminds me, I really should donate blood more often.

  23. Hi I work in a blood bank and work with transfusions nearly daily. This video was awesome at explaining everything about the blood antigens and I really like how they referenced all the other blood groups too! Blood banking is an awesome job that pays really well, if you think this video is cool, check out a medical laboratory scientist (or technician) degree!

  24. My dad was talking about this he’s one of the people that has this rare blood type I believe. He would always talk about how doctors would try to constantly get blood from him and would try to get him to stay longer in the hospital than he need too.

  25. I don't know if I should be happy or worried being O+ being that I can donate to most people but can't accept the other types. Thankfully it's not as rare as these.

  26. 3 vampires went into a restaurant, a rich guy, a middle class guy and a poor guy.

    Each started calling for the waiter:

    Rich – "Bring me your freshest rarest blood." It was served in a bottle and poured in a wine glass. He took a sip, and smirked at the guys on the other tables.

    Middle – "I think I'll just be having blood stew." It was served hot, he blew on it and started eating.

    Poor – "Um, can you get me some hot water first?" The waiter eyed him suspiciously but went on his way and came with a cup of water. "So what will you order sir?" the waiter asked. "Um, I'm still thinking, I'll just call for you". After the waiter walked off, he took out a dried napkin and dunked it in. "Guess I'll just be having tea".

  27. Am i glad i have A positive blood 😂 i am horrible when it comes to phone calls. So the baby would probably have died if it was me they had to rely on as i would never have picked up the phone due to my anxiety..

  28. Could you pls make a video on Bombay blood group. It's rare blood found in Mumbai. It don't have A, B and H antigen. Found in native of Mumbai. Around 1 in 10k its found.

  29. Not sure what my blood type is but I can't donate because they marked in my medical files that I am a biological weapon. They literally told me this. That's because I create a super antibody that will attack the organs of another person and it causes my white blood cell count to increase so dramatically that they think I'm going to die every time I walk into a medical establishment where they've never heard of this condition. If anybody else takes any of my blood or plasma my white blood cells and super antibodies will attack the red blood cells the way they do in me but they will do it to such a degree that it will kill them. They even said one day that my own system could turn on me. Because of this I am anemic. It is also rumored that this condition has the ability to destroy the HIV virus. I thought because of this that they would be interested in using my plasma or blood to develop cures but for some reason they want nothing to do with it. However that has not stopped them from experimenting on me all throughout my childhood until I cut them off. Fed up with being a lab rat. Got tired of living in a sterile bubble. I never get sick anymore even when around sick people however a vaccine could kill me within hours because my white blood cell count and super antibodies would go into overdrive. The average person has a white blood cell count of 3000 to 10,000. My average white blood cell count runs 30,000 to 50000. This is known to kill most people. Little by little I am deteriorating away. I look fine on the outside and you can't tell anything is wrong with me. On the inside I am stricken with extreme pain all the way to my core in every joint and Bone. The story behind all of this is much stranger the deeper you get into it. The description in this video matches quite a bit to what I am living with. I never seem to get a straight answer from these people in these medical establishments and they just seem confused.

  30. how i wish my parents would have done some homework before making babies. my mother tried to kill all her children before we could even be born. thanks to science, I have 8 blood brothers and sisters.

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