Blood transfusions and safety
Several layers of safeguards are in place to make sure that donated blood is safe.
Every two seconds, somebody in the United States needs blood, according to the American Red Cross. More than 36,000 units of red blood cells are needed each day.
With so many Americans depending on this supply, safety is a top priority.
To ensure that our nation's blood supply is safe, the organizations that collect, process and distribute donated blood adhere to five layers of overlapping safeguards.
1. Donor screening
Everyone who volunteers to donate blood is asked a series of questions about factors that can affect the safety of their blood. According to the Red Cross, people may be disqualified temporarily or permanently if they have:
- Had a tattoo in the past 12 months.
- Ever had Creutzfeldt-Jakob disease, or have a blood relative with a history of the disease.
- Ever tested positive for hepatitis B or hepatitis C.
- Had malaria in the past three years.
- Lived in the United Kingdom for three months or more from 1980 through 1996, or spent five years in Europe since 1980.
- Lived in a jail, prison or a detention center for more than 72 straight hours in the past year.
- Had syphilis or gonorrhea in the past year.
- Been diagnosed with AIDS (acquired immunodeficiency syndrome) or HIV (the virus that causes AIDS) or had any symptoms of AIDS.
- Done anything that places them at high risk for HIV.
2. Blood testing
All donated blood goes through specific screening tests, according to the AABB. These tests screen for signs of infections, viruses and antibodies.
- Several strains of hepatitis, a virus that can attack the liver.
- Human T-cell lymphotropic viruses (HTLV-1 and HTLV-2), which can sometimes cause leukemia and nervous system disease.
- Syphilis, a sexually transmitted disease that can invade the heart and nervous system.
- West Nile virus, which is generally spread by mosquitoes, and, in rare cases, can cause swelling of the brain and spinal cord.
- The parasite that causes Chagas disease.
- Zika virus.
Testing methods have become increasingly sensitive and accurate over the years.
3. Donor lists
All agencies that collect donor blood keep a list of deferred donors, people who have been turned away from blood banks for safety reasons. Every donor's name is cross-checked with this list. If the donor's name is on this list, their blood is withdrawn from the blood supply.
All donated blood is held in quarantine until all tests have come back negative.
5. Federal oversight
The U.S. Food and Drug Administration (FDA) requires all blood centers to investigate and correct any problems with blood processing and notify the FDA of anything irregular in distributed blood supplies.
If any donated blood does not conform with all of these regulations, it isn't considered suitable for use, says the FDA.
In some cases, people know ahead of time that they'll need a blood transfusion. Surgeries scheduled in advance, for example, may offer the opportunity to choose the source of blood for transfusion.
Some people donate their own blood ahead of time, and others ask a friend or family member with a matching blood type to donate blood for them. If you're interested in either of these options, called autologous blood transfusion and directed donation, talk to your doctor.