BACKGROUND: The impact of the H1N1 influenza on blood donation is unknown.

STUDY DESIGN AND METHODS: We examined number of blood donors presenting to blood donation centers or bloodmobiles using a blood donation database of Red Cross Hyogo Prefectural Blood Center between 4 weeks before and after May 16, 2009, respectively, when the first case of H1N1 influenza was confirmed in Kobe. The numbers of blood donors per donation site (i.e., blood donation centers and bloodmobiles) and per blood products (i.e., red blood cells [RBCs], platelet [PLT]-poor plasma, and PLTs) were also examined.

RESULTS: The number of blood donors decreased by 21% and whole blood donations declined by 1329 units within 1 week of the first case of H1N1 influenza. While number of blood donors showed a rapid decrease, blood donations returned to the normal level within 1 week. This quick recovery was attributed to the diligent efforts made by Red Cross Centers, including the use of e-mail to encourage blood donation, on-the-street campaigns, and requesting new bloodmobile drives in workplaces and universities. RBCs that were donated in bloodmobiles was predominantly affected; the number of blood donors in bloodmobiles decreased by 39%.

CONCLUSION: H1N1 influenza pandemic had a great but transient impact on blood donation.