Some Swine Flu Questions On Your Mind : Shots - Health News Why does the flu vaccine take so long to make? Why doesn't my doctor test my flu? We have the answers.

Some Swine Flu Questions On Your Mind

With all the questions floating around about swine flu cases and vaccine shortages, we wondered what the Centers for Disease Control and Prevention might tell us at a briefing today.

Turns out, nothing new really. That's because not all that much has changed on the swine flu front. The vaccine is being made by the same companies, the same way, in the same factories as the seasonal flu vaccine that's been used safely for years. And it's still true that the new H1N1 virus has established itself throughout the country, which most of us had sort of figured out just by talking with the neighbors.

So we reflected instead on some of the question we keep getting from NPR listeners and readers of this blog.

First: Why won't doctors test everyone with flu symptoms to see whether they have H1N1?

The answer is simple. If it's the flu, at least right now, it is H1N1 because that's practically the only flu bug in town right. Plus, treatment doesn't depend on knowing which variety of flu might have you down. So you may want to satisfy your curiosity. But epidemiologists, statisticians, and even your doctor don't need to know. Sorry.

Second: Why does the flu vaccine take so long to make?

Because it's grown in eggs, and the virus takes its sweet time growing. This H1N1 virus is a little pokier than some other flu strains, too.

Third: So why exactly is flu vaccine grown in eggs?

Because that's tried-and-true vaccine technology, safely used for years. The federal government has been funding work on new ways to make vaccine, but everything is still in the experimental stage. CDC director Tom Frieden talked about that at his press conference. "We need to get comfortable with a new vaccine process," he said. "I don't think any of us would want in an ideal situation to try a new vaccine in a pandemic."

For more on how flu vaccines are made now and might be made in the future, check out All Things Considered host Robert Siegel's conversation with Robert Belshe, director of the Center for Vaccine Development at St. Louis University.