Experts shift their focus to children’s flu deaths

The government said Thursday that flu is now widespread in 36 states — including Washington — almost everywhere except the upper Midwest and a few Eastern states.

How many will die when it is over? Probably tens of thousands. Beyond that, exact numbers are hard to pin down.

The reason: Most people who catch the flu never go to a doctor. And even if they do, they usually never get a definite diagnosis.

The flu is difficult to distinguish from other winter viruses. In most cases, there is little reason for doctors to go to the trouble of identifying the culprit, which traditionally has required growing the virus in a culture, a process that takes two weeks.

Even if they do, chances are good they will find nothing.

So unlike many less common illnesses, such as botulism, plague and rabies, state health departments are not required to send reports of flu cases or deaths to the Centers For Disease Control and Prevention, which keeps track of disease trends.

Instead, the CDC relies on computer analyses to estimate how many people fall victim each year. However, that may change. In particular, the CDC is interested in learning more about childhood flu cases, especially those that kill.

Spokesman David Daigle said the CDC has been working with the Council of State and Territorial Epidemiologists for the last three or four weeks to gather information on pediatric deaths.

Several states have sent in reports and specimens, giving the CDC a total of about three dozen deaths among children and teenagers.

For now, the best estimate of flu’s toll must wait until the season is over. Using computer analyses, CDC researchers calculate how many people died during the flu season and when flu viruses were not circulating.

The difference, they say, is a rough idea of how many died of the flu that season. Since flu rarely shows up on a death certificate, they narrow the number down by focusing on deaths in a broad category of respiratory and circulatory ills that could result from the infection.

This way, they figure the total number of U.S. flu deaths in an average season is 36,155. However, 90 percent of these deaths are in people over age 65. The estimated number in those under age 5 — 92 — is based on so few cases that it could be way off in any year.

"When you say 92, it gives an image of real precision, but in fact it’s a ballpark estimate," said Dr. Keiji Fukuda, the CDC’s top flu epidemiologist.