By Ashley Hayes
WebMD Health News
Reviewed by Arefa Cassoobhoy, MD, MPH
Jan. 5, 2015 -- The flu is increasing in intensity and spreading throughout much of the country, the CDC said in its weekly flu update.
Latest Cold and Flu News
And it will get worse before it gets better.
"Flu activity is expected to continue in the coming weeks, with increases occurring especially in those states that have not yet had significant activity," according to the CDC.
"Nationally, the country is likely to continue to experience several more weeks of flu activity. ... Most of the northeast and west of the country has yet to experience the full brunt of the flu season."
Only one state, Hawaii, reported "sporadic" flu activity through Dec. 27, according to the agency. Six more -- California, Oregon, Nevada, Arizona, Alaska, and Maine -- reported significant activity, along with Puerto Rico. The flu was at "widespread" levels in the other 43 states, an increase from 36 the previous week.
Another six flu-associated deaths of children were reported, bringing the total to 21 this season. With the exception of the 2009 flu pandemic, deaths of children from the flu have ranged from 37 to 171 since 2004-2005, when they began to be reported, the CDC said.
The CDC doesn't track adult deaths from the flu. But the number of deaths in which pneumonia or influenza was listed -- which was at an "epidemic threshold" for the week ending Dec. 20 -- has declined this week. It's "once again below the epidemic threshold," the agency says. The flu season is said to have reached epidemic levels when the proportion of deaths attributed to pneumonia and the flu reaches a certain level. That threshold changes week to week.
Get Vaccinated, Officials Say
This year's dominant flu strain is H3N2, a type of the flu virus that tends to be more serious, officials have said. It's also "drifted" from the strains included in the flu vaccine, meaning the vaccine is not as effective as hoped.
Seasons dominated by H3 viruses tend to have more hospitalizations and deaths, CDC Director Tom Frieden, MD, said last year.
So far, H3N2 viruses account for more than 95% of all flu cases reported to the CDC this season.
Although the vaccine hasn't worked as well as hoped, health officials continue to recommend it. It still can prevent infection with some flu strains and flu-related complications in some people. Also, it's common for there to be two waves of flu activity during a typical season, with the second caused by a different flu virus, the CDC says. As of early November, only 40% of people in the U.S. reported getting a flu vaccine this year.
Health officials also recommend antiviral drugs to treat the flu in some people, including children or those who are very ill or at risk of flu-related complications. The drugs can help shorten the length of the flu and make it less severe. But media reports suggest that at least one of those drugs, Tamiflu, might be in short supply in some areas.
SOURCES: CDC: "FluView Weekly Report Summary." Press release, CDC.
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