some hospitals are taking extreme measures. Tents set up in the parking lot. Here's abc's chief medical editor, dr. Richard besser, now. Reporter: Emergency rooms in texas -- most of the people we see... See More
some hospitals are taking extreme measures. Tents set up in the parking lot. Here's abc's chief medical editor, dr. Richard besser, now. Reporter: Emergency rooms in texas -- most of the people we see at the e.R. Have not gotten the flu shot and their symptoms are pretty severe. Reporter: California -- significant increase in the amount of flu-like illness patients walking into our emergency department. Reporter: New york -- people may say it's just the flu. But I've seen people die from just the flu. Reporter: More than 60% of hospitalized flu patients are between the ages of 18 and 64. That's almost twice as many as last year. Like this mother of three. Healthy and so young. Just 29. She had a cough and runny nose and everything like that. Reporter: Both alice jones and her husband, darell, came down with the flu last week. He recovered. She ended up in the hospital, short of breath, convulsing. And monday, dying. My youngest, she asked me, when are we going to go pick up mommy? Reporter: They're just two of the thousands who the flu has infected. Look at google flu trends for this week. 37 states with high flu activity. H1 flu viruses affect younger people more than older people, compared to other types of flu viruses. This is just heartbreaking. Dr. Besser with us now. Rich, a lot of people are going to look at this and wonder how a 29-year-old healthy mom can die of the flu. It's so sad. It makes the point that anyone at any age can die of the flu. Healthy, young adults tend not to get as vaccinated as frequently. They weren't around the last time this was around. And they don't have existing immunity. She believes behind three children. You were telling me that one of them has been diagnosed with the flu. One has the flu. The others have been vaccinated. It's a point for everyone watching tonight. If the flu is in your community, it's not too late to get vaccinated. And this particular vaccine covers this strain? It will take two weeks to be fully protected. Within a matter of days, you'll have some protection.
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