WASHINGTON (Reuters) - The new influenza strain circulating around most of the United States is putting a worrying number of young adults and children into the hospital and hitting more schools than usual, U.S. health officials said on Monday.
The H1N1 swine flu virus killed a vice principal at a New York City school over the weekend and has spread to 48 states. While it appears to be mild, it is affecting a disproportionate number of children, teenagers and young adults.
This includes people needing hospitalization -- now up to 200, said Dr. Anne Schuchat of the U.S. Centers for Disease Control and Prevention.
"That's very unusual, to have so many people under 20 to require hospitalization, and some of them in (intensive care units)," Schuchat told reporters in a telephone briefing.
"We are now experiencing levels of influenza-like illness that are higher than usual for this time of year," Schuchat added. "We are also seeing outbreaks in schools, which is extremely unusual for this time of year."
New York City Health Commissioner Dr. Thomas Frieden agreed with Schuchat.
"We're seeing increasing numbers of people going to emergency departments saying they have fever and flu, particularly young people in the 5 to 17 age group, " Frieden, who has been named by U.S. President Barack Obama as the new CDC director, told a news conference.
About half of all cases of influenza are being diagnosed as the new H1N1 strain,
while the rest are influenza B, or the seasonal H1N1 and H3N2 strains. Flu season in the United States is usually almost over by May.
CDC officials say around 100,000 people are likely infected with the new flu strain in the United States and Schuchat said the 5,123 confirmed and probable cases and six deaths in the United States were "the tip of the iceberg.