While the September 11, 2001 attacks on the World Trade Center and Pentagon forced us to stare into the face of evil, the nation’s response to the attacks gave us faith in the restorative powers of kindness. Among the many acts of compassion was an upsurge in the number of people who donated blood.

Short-term increases in the number of blood donations following national disasters have been documented. But we don’t know as much about the long-term impact on the blood supply. In other words, do people who donate blood after a national disaster—particularly first-time donors—continue to donate blood in non-disaster situations? Another concern is the safety of donated blood because first-time donors are more likely to have transfusion-transmissible viral infections (TTVIs) than people who donate blood regularly.

In a study reported in the May 7, 2003 Journal of the American Medical Association , researchers found that the events of September 11, 2001 resulted in an increase in first-time donors, without substantial increase in risk of TTVIs. However, blood donations have declined since the post-9/11 period, with most people who donated for the first time after the attacks not returning to donate blood regularly.

About the Study

The researchers used data collected by the National Heart, Lung, and Blood Institute’s Retrovirus Epidemiology Donor Study (REDS), which has collected information about blood donations including demographic characteristics of donors, first-time or repeat-donor status, and results of screening tests for TTVIs at five blood centers since 1991.

The researchers used this data to characterize the volume of donations and prevalence of infectious disease markers in blood donated during the four weeks before and after 9/11 and to compare it to blood donations made during the corresponding period of 2000. They also measured the return rate of donors who donated blood for the first time following 9/11.

The study included 327,065 blood donors who made 373,628 blood donations at five large, regional blood centers during the eight weeks surrounding September 11 in 2000 and 2001.

The Findings

As expected, the number of blood donations in the weeks after the September 11, 2001 attacks was markedly greater than in the corresponding weeks of 2000 (2.5 times greater in the first week after the attacks; 1.3–1.4 times greater in the second to fourth weeks after the attack).

The number of first-time donations increased 5.2 times in the week after September 11, 2001 compared to the four weeks preceding the attacks (22,700 donations compared to 4000); repeat donations increased 1.5 times during this period, to 26,400 donations during the week after the attacks compared to an average of about 16,400 during the four weeks before the attacks.

Donations confirmed positive for human immunodeficiency virus (HIV) , hepatitis C (HCV) , and hepatitis B nearly tripled from one week before September 11, to one week after (from 0.1% to 0.3%), but the risk of actually transmitting the viral infections through a transfusion increased only slightly.

The number of first-time donors who returned for a subsequent donation within one year did not change much for the years starting September 12, 2000 or September 11, 2001 (about 28% returned each year).

How Does This Affect You?

Not surprisingly, the weeks immediately following the attacks of September 11 saw a surge in the number of blood donations. Among the most striking characteristics of these donors was the number of people who were donating blood for the first time—without a significant impact on blood safety.

More concerning was the lack of first-time donors who returned within one year for a repeat donation. Blood is a perishable product, and supplies must be continually replenished. There is an ongoing need for blood and blood products. While donating during a crisis is commendable, healthy donors should remember the importance of donating blood even without an emergency. It shouldn’t have to take a national tragedy to bring us together as a community.