NEW YORK, May 21 (UPI) -- People born before 1957 appear to have some immunity to H1N1, the swine flu virus, federal health officials say.
Tests on blood serum from people at least 52 years old show they had antibodies that attacked the new virus, Dr. Daniel Jernigan, chief flu epidemiologist at the Centers for Disease Control and Prevention, told The New York Times.
This is a trend American and Mexican doctors have noticed, though it does not mean that everyone over 52 is immune, the report says.
It does point out, however, that the new flu infects and hospitalizes many more young people than seasonal flu outbreaks which tend to sicken and kill the very old.
Jernigan says only 13 percent of the 247 people hospitalized because of the swine flu are over 50 years old. Many of those have other medical problems. In a typical flu season, more than 90 percent of those hospitalized are older than 50.
There have been eight deaths in the United States from the H1N1 virus.
