Via Times of India :
" MUMBAI: Three types of influenza viruses are circulating in Mumbai's air, with the most "potent and predominant" H1N1 affecting people even more than the seasonal flu, experts told TOI, providing a possible explanation for the deluge of fever and cold complaints at city hospitals.
The observation about the three strains was made by virologists working with Haffkine Research Institute, who, between June and August this year, studied 500 patients admitted for influenza-related ailments in various hospitals. Of the 500 patients studied, the institute found that about 23 % tested positive for H1N1, while about 11 % were positive for the seasonal flu.
Surprisingly, 8% of the samples tested positive for influenza B, a relatively less virulent influenza strain that did not surface in Mumbai last year."