What is the new 'triple mutant variant' of Covid-19 virus found in Bengal? How bad is it? India Today Web Desk triple mutant variant Bengal strain covid19 Covid-19 transmission in India is exploding at a rate unseen anywhere in the world so far. On Thursday, the country reported 3.14 lakh new cases, the highest single-day count for any country ever, and deaths too are mounting every hour. Amid this, a new variant of the virus causing Covid-19 has been detected in West Bengal. The 'triple mutant variant' (also being referred to as the 'Bengal strain' of Covid-19) is reportedly more infectious than other strains.