Flu season begins: What you need to know

Minnesota recorded its first pediatric death from flu this season and cases of the flu are increasing rapidly in southern Minnesota, the Twin Cities metro area and in the central part of the state.

How widespread is flu?

The flu outbreak is classified by the state health department as regional. That means there's been a notable increase in cases in a few areas of the state. As more regions become involved, the flu outbreak will be considered widespread.

There have been more than 100 positive flu tests in the past week processed by the clinic and hospital laboratories that report flu information to the Minnesota Department of Health. That's more than double the number of positive results that were reported the previous week.

But in terms of hospitalizations, there wasn't much of a change from the previous week. There were 18 hospitalizations, compared to 26 the week before. As more information arrives, a few more cases might get added to last week's tally. But that's not a lot of hospitalizations compared to peak flu season, when it's not uncommon to see hundreds of flu hospitalizations in a week.

What do we know about the first pediatric flu death this season?

Health officials are not releasing any details to protect the child's identity, so we don't know if the child had a pre-existing medical condition that would have made him or her more susceptible to flu, or whether the child was vaccinated against influenza.

But even if the child had been vaccinated, the health department officials say it's still possible to get the flu and even with vaccine protection the virus can cause really serious disease in some people, especially among children and seniors.

Have there been any flu deaths among adults this season?

We don't know. The Health Department does not publish data on flu deaths among adults. The agency used to do this, but it changed the way it counts flu cases, so it no longer publishes that data. But pediatric influenza deaths are a national notifiable disease event, so the health department does track and publish that information. Last year Minnesota had two pediatric deaths from flu.

Federal health officials said that some of the flu that's circulating this season has mutated enough that it doesn't match the strain covered by the flu vaccine. Is that true in Minnesota, too?

Possibly, though the health department doesn't yet have the data to show whether our predominant flu strain has changed and no longer matches well with the vaccine.

But even if it has changed, the department is still recommending that people get vaccinated for flu because they say it might offer enough protection to lessen the severity of the illness.

And depending on the type of vaccine you get, it can offer protection against three or even four strains of flu. Usually more than one strain of flu is circulating at a time.

Is it worth getting vaccinated now when flu is already circulating?

It takes about two weeks for a person to build up immunity to flu after being vaccinated. So, if you get vaccinated in the next week or so, presumably you would have protection against flu before the holidays — and that's a time when you often see flu cases spike because people are spending so much time together.