Washington: Swine flu - influenza A (H1N1) pandemic 2009 virus - that has killed over 1,500 people and left more than 27,000 people infected in India has acquired mutations that make it more dangerous than previously circulating strains of H1N1 influenza, a team of Indian-origin scientists from the Massachusetts Institute of Technology (MIT) has discovered.

The findings, reported in the scientific journal Cell Host & Microbe, contradict previous reports from the Indian health officials that the strain has not changed from the version of H1N1 that emerged in 2009 and has been circulating around the world ever since.