KHQ MD ALERT: Flu Spreads To 50 States, But Rate Levels Off - Spokane, North Idaho News & Weather KHQ.com

NBCNEWS.COM - The flu is everywhere, with influenza reported in all 50 states, but overall it seems to be leveling off, federal health officials reported on Friday.

Nonetheless, this flu season is a tough one, hitting people over 65 the hardest but also putting many young adults and children into the hospital. So far, 37 children have died of flu, the Centers for Disease Control and Prevention reports. Half of the people hospitalized for flu were 65 and older.

The CDC also reports the first case of a flu virus that resists the effects of the most commonly used flu drug, Tamiflu. Flu viruses have already evolved to resist the effects of the two oldest flu drugs, amantadine amd rimantadine.

"Influenza activity remains elevated in most of the country. Like last week, some national indicators are declining while others are increasing," the CDC said in a statement.

"Nationally influenza-like-illness seems to be leveling off, however some parts of the country are continuing to show increases." Flu is spreading more in the southwest and northwest, but on the decline elsewhere.

"A total of 37 influenza-associated pediatric deaths have been reported during the 2012-2013," CDC said. This number can vary a lot: 122 children died in the 2010-2011 season and 34 died last year.

The CDC decides whether flu is epidemic by comparing flu infections to those for the same week in previous years. Last week, 9.8 percent of all people who died succumbed to pneumonia and influenza – above the epidemic threshold of 7.3 percent for that week.

"Key indicators reflecting severity (hospitalizations and deaths) increased again this week, with the greatest impact among people 65 and older," CDC added.

But flu isn't the only virus causing misery, or even the main virus. Only 26 percent of people who visited the doctor and who were tested for influenza actually had flu, the CDC says. There's also a new strain of norovirus, commonly called stomach flu, spreading across the country, along with the usual winter assortment of colds and viruses from respiratory syncytial virus to parainfluenza virus.

The CDC says everyone over the age of 6 months should be vaccinated for flu every year. So far, 133 million doses of flu vaccine have been distributed – the CDC doesn't track how many people actually got shots or nasal sprays.

The agency reminded people they can get prescription drugs for flu, which are the most effective if taken as soon as symptoms start. But there was one case of a person whose infection wasn't helped by Tamiflu, known generically as oseltamivir. "The first oseltamivir-resistant 2009 H1N1 virus detected in the U.S. during the 2012-2013 influenza season is being reported this week," CDC said.

"The majority of currently circulating influenza viruses are susceptible to the neuraminidase inhibitor antiviral medications oseltamivir and zanamivir; however, rare sporadic cases of oseltamivir-resistant 2009 H1N1 and A (H3N2) viruses have been detected worldwide." Zanamivir, known by the brand name Relenza, is administered through the nose. Tamiflu is available as a pill or liquid.