One of the worst flu outbreaks in the United States in almost a decade worsened last week and will likely linger for several weeks, causing more deaths, the Centers for Disease Control and Prevention said on Friday.
It is not clear why this flu season is so intense and so unusually widespread - still causing wide swaths of misery in 48 states and high levels of illness in 43 of them, as of February 3.
The season is now in its 11th week, and Schuchat said flu is so hard to predict, it's not clear whether cases have yet reached their peak.
In the latest update, the federal Centers for Disease Control and Prevention reported the highest flu hospitalization rate seen since the agency started keeping comparable records in 2010 and the highest rate of flu-like illnesses since the flu pandemic of 2009. In the last five years, influenza-like activity in the USA has remained elevated anywhere from 11 to 20 weeks, meaning there could still be several more weeks of increased flu activity. The CDC considers the 2014-15 season "moderately severe" with high levels of illness, hospitalizations and deaths compared to previous seasons and has used it as a comparison to the current season.
The CDC said at least 63 children have died this flu season, up from 10 reported last week. "We could potentially see several more weeks of increased flu activity".
National Institutes of Health (NIH) National Institute for Allergy and Infectious Diseases Director Anthony Fauci discussed ongoing research to develop more effective seasonal and pandemic flu vaccines, including a universal flu vaccine.
"There might be a second wave of influenza B infections", she said.