Danger of wrong blood type! Who can donate to whom?
"Let’s explore and understand the blood group system and why knowing your own blood type is so important, along with updated information on which blood types can donate to or receive from others.
In the case of a hospital error where a wrong blood type was given to a victim injured by falling concrete on Rama II Road—an error that may have contributed to their subsequent death—
Let’s take a moment to better understand the concept of “blood type,” also commonly referred to as “blood group.” In fact, there are over 40 known blood group systems, but two are particularly important:
ABO System – Divides blood types into four groups: A, B, O, and AB.
Rh System – Divides blood types into Rh positive and Rh negative. Rh-negative blood is rare in Thai people (only about 3 in 1,000 Thais have Rh-negative blood), making it a rare blood type.
When it comes to blood transfusions, many blood group systems may be relevant, but the ABO system is the most critical.
What is the ABO blood group system?
According to the Faculty of Medicine Siriraj Hospital, the ABO blood group is determined by the presence of specific antigens on the surface of red blood cells. There are two main types: A antigen and B antigen.
Individuals lacking a particular antigen will produce antibodies against that antigen.
If someone receives an incompatible blood type, these antibodies can trigger a severe immune reaction that may be life-threatening.
Here’s a breakdown:
Blood group A: Has A antigens; produces anti-B antibodies.
Blood group B: Has B antigens; produces anti-A antibodies.
Blood group AB: Has both A and B antigens; produces no ABO antibodies.
Blood group O: Has neither A nor B antigens; produces both anti-A and anti-B antibodies.
ABO Blood System and Compatibility for Transfusions
The ABO system’s antigens and naturally occurring antibodies (developed from environmental exposure such as food) determine transfusion compatibility.
Ideally, blood transfusions must match the recipient's blood type exactly. For example, a patient with blood type A should receive blood type A.
However, in emergencies where a matching type is unavailable, doctors may use substitute types that are safe for the recipient:
Type O blood
Can be given to all blood types: A, B, AB, and O
Can only receive blood from type O
Type A blood
Can be given to A and AB
Can receive blood from A and O
Type B blood
Can be given to B and AB
Can receive blood from B and O
Type AB blood
Can only be given to AB
Can receive blood from all types
Thus:
Type O is known as the Universal Donor: can donate to all blood types but only receive from O.
Type AB is known as the Universal Recipient: can receive from all blood types but can only donate to AB.
Importantly, incompatible transfusions can lead to destruction of red blood cells and cause serious or fatal complications.
What’s the most common blood type among Thai people?
According to the Thai Society of Hematology:
O is the most common: 38%
B is second: 34%
A is third: 21%
AB is the least common: 7%
Note: While people with AB blood can receive type O blood, doctors typically consider giving them type A or B blood first—depending on which type is more available in the blood bank.
