It's estimated that the Spanish flu pandemic of 1918 killed anywhere from 50 million to 100 million people worldwide. That's no small number. It's much larger, in fact, than the 20 million fatalities caused by World War I, which was coming to a close at that time.

A pandemic of such proportions is unfortunately still within the realm of possibility. World health experts are particularly concerned about bird flu causing a pandemic. Vaccines are the best defense against such a pandemic. But drug manufacturers are currently unable to meet demand even for seasonal flu. Without an adequate supply of effective vaccine, a full-blown pandemic could have devastating consequences.

In light of these sobering facts, today's story -- about a new method for "stretching" a bird flu vaccine -- is encouraging. The additive, technically known as an adjuvant, would multiply the effectiveness of bird flu vaccine 25 times. This would allow 25 people to use a dose that was previously only effective for 1 person.

Scientists are intrigued, yet encouraged, by today's announcement. In the words of the virologist John Oxford:

We were all very pleased to see the results, and very surprised that the adjuvant broadened the immune response and range of avian influenza viruses. The results exceeded expectations, but it's not crystal clear how the adjuvant works.

Spanish flu influenza bird flu avian flu pandemic vaccine adjuvant