Many survivors of the 1918 flu pandemic appear to be immune to the current swine flu, but not to seasonal flu, says a University of Wisconsin researcher.
Yoshihiro Kawaoka also found that swine flu multiplies more severely in the respiratory system than seasonal flu, the Associated Press reported. In tests on mice, ferrets and monkeys, he found that the swine flu is present in greater numbers throughout the respiratory system instead of staying in the head, like common winter flu.
Kawaoka said the findings make him more concerned about the potential threat posed by swine flu, the AP reported.
The research was published Monday in the journal Nature.