Health Information Provided by Health Testing Centers
Date Published: February 9, 2012
Author: Karen Alton, LPN
Blood Types, Facts, and Donation
Everyone, regardless of age, gender or ethnicity, relies on blood to
survive. As a result there is a constant need for all blood types. The
available supply of blood is dependent on donations made by eligible
individuals throughout the country. There is however, often a fear that
is associated with the act of donating blood. Education is the best way
to promote blood donation, overcome any fears about the process and help
maintain the blood supply at a level that meets the current need.
The ABO Blood Group System
- Blood is categorized in four primary types, or groups, based off of
the ABO system. The four potential blood types are A, B, AB, and O.
- Antigens that are on the surface of red blood cells are either type A
or they are type B. Their presence, or absence, determines whether
blood is a type A or B. Blood groups are determined based off of these
- Blood types must be accurately matched for a safe red blood cell
transfusion. People with type O blood can donate to all blood types and
people with type A blood can donate to people with type A and type AB. A
person with type B blood can safely donate to people with type B and
type AB. If a person has type AB blood, he may donate red cells only to
others with type AB.
- The presence of the Rh protein, or factor, in blood also helps
determine a person’s blood type. The Rh factor is another type of
antigen that may or may not be present in the blood. If it is present,
the blood type is positive. If the Rh protein is absent, it is negative.
- Type O negative blood is the universal red cell donor. This means
that a person that is O negative can donate his blood to anyone
regardless of that person’s blood type. Type AB positive is the
universal plasma donor. This means that a person with this blood type
can donate blood to anyone.
Blood Types and Population
- Not all ethnic groups have the same percentage of blood type combinations. The mix of blood types varies by ethnic group.
- At two percent, Hispanics have the lowest percentage of AB positive.
Asians, at seven percent, have the highest percent of AB positive blood
- Hispanics have the highest percentage of O positive blood at 53
percent. Caucasians have the lowest percentage of O positive blood.
- Overall, the most common blood type is O positive.
- Matching both ethnic background and ABO blood type can at times
provide a closer blood match. This can reduce the chance of a reaction
in some cases and help in the treatment of certain ethnic specific
conditions, such as sickle cell disease.
How is My Blood Type Determined?
- A person's blood type is determined by a combination of two genes, one from each parent.
- Blood typing is not enough to determine paternity.
- A child whose parents both are type A, the child will potentially be
a type A or a type O. If both parents are a type B, than he will be
either a type B or an O.
- When one parent is a type A and the other a type B, the child may have any of the four blood types.
- When one parent is a type AB and the second parent is either AB, A, or B, the child will be a type AB, A or B.
Blood Facts and Statistics
Facts About Blood Needs
- Diseases such as sickle cell and cancer require blood transfusions. Cancer patients may require transfusions on a daily basis.
- The amount of red blood cells needed for a transfusion is three pints.
- In the United States, blood is needed every two seconds.
- To meet the need for blood, there must be 38,000 blood donations daily.
- Victims of car accidents may require as much as 100 pints of blood on average.
Facts About the Blood Supply
- At present, there is no way that blood can be manufactured. It can only be collected by donors.
- There are roughly five million patients that receive blood yearly.
- There are 9.5 million blood donors in the United States.
- Less than 38 percent of people living in the United States are eligible to give blood.
- In the United States, 16 million donations of blood are collected in a year.
Facts About the Blood Donation Process
- Sterile needles used to collect blood are single use only.
- Before releasing donated blood to hospitals, it is tested for
infectious diseases, such as Human Immunodeficiency Virus (HIV),
hepatitis B and C and syphilis.
- Red blood cells may be donated every 56 days. When double red cells are donated, there must be 112 days between donations.
- Platelets may be donated up to 24 times a year. Seven days must pass between donations.
- The donation process takes an hour and 15 minutes. The portion of
this process that involves having the blood drawn for donation takes no
more than 12 minutes.
Facts About Blood and Its Components
- A single blood donation can save three lives. This is because up to
three transfusable components are taken from a pint of donated blood.
These components, red cells, platelets, cryoprecipitate and plasma, are
derived from blood.
- Apheresis is a process in which donors can donate blood components only.
- Red blood cells have a shelf life of 42 days following donation.
- Platelets are outdated after five days.
- Red cells, platelets and plasma are replenished by healthy bone marrow.
Facts About Donors
- In the United States, seven percent of people have O negative blood type.
- When a person's blood type is unknown in emergency situations, O negative is used.
- In the U.S., only three percent of the population has blood that's type AB.
- The percentage of people in the United States with type O blood that's either positive or negative is 45 percent.
- Both men and women donate blood equally.
Facts About American Red Cross Blood Services
- Forty percent of the blood supply in the United States comes from the Red Cross.
- The American Red Cross and its sponsors hold over 200,000 blood drives yearly.
- Approximately 3,000 hospitals in the United States receive blood from the Red Cross.
- Twenty percent of donated blood comes from Red Cross donor centers,
while 80 percent comes from mobile blood drives at various locations.
What Happens to Donated Blood?
Step One: The Donation Process
- The donor completes the registration process.
- The donor provides a medical history and undergoes a mini physical examination.
- Blood is donated. The Red Cross collects several test tubes and one pint of blood from the donor.
- Identical barcoded labels are placed on the donor's record, the bag and test tubes of blood.
- The donated blood is placed in coolers of ice where it is kept until it is taken to the Red Cross Center.
Step Two: Processing Procedure
- The test tubes are sent to be tested.
- The Red Cross scans the blood donation into its database.
- The donated blood is placed in a centrifuge and spun to separate the transfusable components.
- The Red Cross then leukocyte-reduces the red cells.
- Platelets are also leukocyte-reduced and they are bacterially tested.
Step Three: Testing Process
- There are five Red Cross National Testing Laboratories. The test
tubes are sent to and then received by one of these laboratories.
- Each unit of blood undergoes a dozen tests. These tests are checking
for infectious diseases and are meant to establish the blood type.
- Within 24 hours, results of the tests are electronically sent to the manufacturing facility.
- The donor is notified if the tests return positive for infectious diseases. The donated blood is discarded.
- The testing in this step occurs at the same time as Step two.
Step Four and Five: Storage and Distribution
- Labels are placed on units of blood that undergone testing and are found to be safe.
- Refrigerators that are kept at six degrees Celsius are used for storing red cells. Red cells are stored for 42 days only.
- Agitators are used to store platelets at room temperature. They are kept for no longer than five days.
- Freezers are used to freeze and store plasma and cryo for one year.
- Shipping of blood can occur at any time, seven days a week and at any hour.
An article written by the Mayo Clinic that defines blood
donation. This article outlines the different types of blood donation
and what the eligibility requirements are.
WebMD: What is Blood Donation?
This website explains what blood donation is and why it is
necessary. It also discusses who can and cannot donate blood and why.
Other topics covered include, what to do before donating, what happens
when donating and the potential risks of donation.
Medline Plus: Blood Transfusion and Donation
This page is about both blood donations and transfusions. It
discusses the need for blood transfusions and fears that people have
about donating and receiving blood.
Genetic Science Learning Center
This page from the University of Utah explains blood types. It is
an in-depth overview of the ABO system and what determines blood type.
The Franklin Institute: Blood
An explanation of Rh Factors and how they were discovered. This
provides an explanation of what makes someone Rh positive or negative
and how it is connected to blood type.