Several cases of coronavirus mutation have been observed in Maharashtra, a senior scientist told NDTV today, underscoring that they are yet to observe behaviour - including how fast or slow it infects people -- and pointed out that it is "too early to call it a strain". Dr TP Lahane, the Director of Medical Education and Research, Maharashtra, told NDTV that it is early days yet and more sequencing and study needs to be carried out to know about the "infectiveness" of the mutant variety.