Playing chicken with the flu
We have been making vaccine against each year's flu outbreaks the same way for over 60 years. A virus believed to be the best match for the one likely to be circulating in humans is grown in fertilized hens' eggs, then killed and turned into vaccine. "This way of making vaccines is archaic," says Adel Mahmoud, a physician and president of Merck Vaccines. And it would be cumbersome at best for the new avian flu. A mutation in the virus's coat has made it especially dangerous, and it would have to be genetically engineered to be less so before it could be grown in eggs. After that, clinical trials would be needed to see if the engineered vaccine still works, and at what dose, adding months to an already long process. The CDC, the Food and Drug Administration, and the National Institutes of Health are planning for this, but it's an open question whether an effective vaccine could be ready for mass use if the avian flu becomes a human threat.
So just as this year's flu season is winding down, the looming prospect of one far worse is teaching some hard lessons. As we confront the immediate threat, we should make a national commitment to develop flu vaccine technology fit for the 21st century, based on harmless viruses genetically engineered to stimulate immunity or even on designer proteins. The pandemic scare--whether it becomes reality or not--may be a needed wake-up call.