Government health officials are mobilizing to launch a massive swine flu vaccination campaign this fall that is unprecedented in its scope — and in the potential for complications.
The campaign aims to vaccinate at least half the country’s population within months. Although more people have been inoculated against diseases such as smallpox and polio over a period of years, the United States has never tried to immunize so many so quickly.
But even as scientists rush to test the vaccine to ensure it is safe and effective, the campaign is lagging. Officials say only about a third as much vaccine as they had been expecting by mid-October is likely to arrive by then, when a new wave of infections could be peaking.
Among the unknowns: how many shots people will need, what the correct dosage should be, and how to avoid confusing the public with an overlapping effort to combat the regular seasonal flu.