Norwegian scientists say they've discovered a mutated version of swine flu in two patients who died and another who is severely ill. The mutation "could possibly make the virus more prone to infect deeper in the airways and thus cause more severe disease," said the nation's health institute. Bottom line from health officials in the US and with WHO: It's not a huge surprise and is no cause for alarm.
"It seems that the mutated virus does not circulate in the population, but might be a result of spontaneous changes which have occurred in these three patients," said the Norwegian government statement. Such mutations are normal, but this one merits "special interest," it noted. The good news is that it's not spreading, one American specialist tells the Washington Post, because "easily transmissible" mutations are the ones to worry about. (Read more swine flu stories.)