Do you know your blood type? How does it matter?
Top Dubai official answers the question ahead of World Blood Donation Day
Dubai: Knowing one’s blood type is extremely important, a top health official in Dubai has said, referring to how many people remain unaware unless they’ve specifically had it tested for medical reasons.
Speaking to Gulf News in an exclusive interview ahead of World Blood Donation Day on June 14, Dr. May Raof - Head & Medical Director of Blood Donation Centre – Dubai Health, said, “In some regions, blood type information isn’t routinely collected unless there’s a medical necessity. But knowing one’s blood type is important for medical treatment, particularly in emergencies or if someone needs a blood transfusion.”
She said, “If the blood group is known, then compatible blood can be transfused immediately without delay. Transfusing compatible blood is critical as transfusion of incompatible blood can lead to severe transfusion reaction, resulting in complications such as kidney failure, circulatory failure, shock, or possibly, even death.”
She said although blood groups can be identified by requesting for blood group tests in any clinic or hospital against a charge, it is free of charge if one donates blood at the Blood Donation Centre at Dubai Health.
Educating the public about the fundamentals of blood groups, she said of the 44 human blood group systems, the ABO and Rh are the two most important.
ABO blood group system
Dr Raof said the basis of ABO grouping is of two antigens - antigen A and antigen B. The ABO grouping system is classified into four types based on the presence or absence of antigens on the red blood cells surface and plasma antibodies:
• Group A – Contains antigen A and antibody B.
• Group B – Contains antigen B and antibody A.
• Group AB – Contains both A and B antigen and no antibodies (neither A nor B).
• Group O – Contains neither A nor B antigen and both antibodies A and B.
Rh blood group system
According to Dr Raof, about two-thirds of the population contains the third antigen on the surface of their red blood cells known as Rh factor or Rh antigen; this decides whether the blood group is positive or negative. If the Rh factor is present, an individual is rhesus positive (Rh+ve); if an Rh factor is absent, the individual is rhesus negative (Rh-ve).
She said this makes for eight common blood types:
A positive (A+), A negative (A-), B positive (B+), B negative (B-), AB positive (AB+), AB negative (AB-), O positive (O+) and O negative (O-).
“Blood group B+ is the commonest and AB- the rarest,” she noted.
Dr Raof said knowledge of blood groups is essential for blood donation.
Saving lives
While many people dismiss blood donation as a routine procedure, it is a voluntary procedure that can save lives at the most critical times.
“There are several types of blood donation and each type of donation helps meet different medical needs,” she shared.
Type A+ can donate only to A+ and AB+; can only receive from A+, A-, O+, and O-
Type A- can donate only to A+, A-, AB+, and AB-; can only receive from A- and O-
Type B+ can donate only to B+ and AB+; can only receive from B+, B-, O+, and O-
Type B- can donate only to types B+, B-, AB+, and AB-; can only receive from B- and O-
Type AB+ can donate only to AB+; can receive from all blood types
Type AB- can donate only to AB+ and AB-; can only receive from A-, B-, AB-, and O-
Type O+ can donate only to blood types A+, B+, AB+, and O+; can only receive from O+ and O-
Type O- can donate to all blood types. It is known as the universal donor type; can only receive from O-
According to her, “Whole blood donation is the most common type of blood donation where one donates about a pint (450 ml) of whole blood. The blood is then separated into its components — red cells, plasma and sometimes, platelets.”
The procedure by which the blood of a person is passed through an apheresis machine that separates out one particular component of blood and returns the remainder to the circulation is called apheresis.
“These blood components include red cells, plasma and platelets. The machine then returns the remaining parts of the blood back to the person. Platelet donation (plateletpheresis) collects only platelets. Platelets are the cells that help stop bleeding by clumping and forming plugs in blood vessels (clotting). Donated platelets are commonly given to people with clotting problems or cancer and people who will have organ transplants or major surgeries,” Dr Raof said.
Double red cell donation by apheresis allows one to donate two units of concentrated amount of red blood cells. Donated red blood cells are typically given to people with severe blood loss, such as after an injury or accident, and people with anaemia (low haemoglobin).
On the other hand, plasma donation (plasmapheresis) collects the liquid portion of the blood (plasma) and helps blood clot and contains antibodies that help fight off infections. “Plasma is commonly given to people in emergency and trauma situations to help stop bleeding,” she noted.
Dr Raof said the voluntary process of donating blood entails five simple steps: Reading educational material about blood donation ( available on Dubai Health website and through DAMMI Smart service as part of Dubai Health Mobile application); registration; filling up donor history questionnaire; medical check up; phlebotomy/blood donation; and refreshment and rest.
Who can donate blood to whom?
Blood transfusion is very specific and calls for the right match from a donor. The possibilities for each of the eight blood groups is as under:
Type A+ can donate only to A+ and AB+; can only receive from A+, A-, O+, and O-
Type A- can donate only to A+, A-, AB+, and AB-; can only receive from A- and O-
Type B+ can donate only to B+ and AB+; can only receive from B+, B-, O+, and O-
Type B- can donate only to types B+, B-, AB+, and AB-; can only receive from B- and O-
Type AB+ can donate only to AB+; can receive from all blood types
Type AB- can donate only to AB+ and AB-; can only receive from A-, B-, AB-, and O-
Type O+ can donate only to blood types A+, B+, AB+, and O+; can only receive from O+ and O-
Type O- can donate to all blood types. It is known as the universal donor type; can only receive from O-
Did you know?
Karl Landsteiner, an Austrian scientist discovered the ABO blood group system in the year 1900. The ABO blood group system consists of four types of blood group – A, B, AB, and O and is mainly based on the antigens and antibodies on red blood cells and in the plasma. Both antigens and antibodies are protein molecules in which antigens are present on the surface of Red Blood Cells and antibodies are present in the plasma.
In the Rh system, the most important antigens are D, C, c, E, and e. If the Rh D factor is present, an individual is rhesus positive (Rh+ve); if an Rh factor is absent individual is rhesus negative (Rh-ve).