A day after India put a total ban on exports of hydroxychloroquine, a malaria drug that US President Donald Trump has touted as a “game changer" in the fight against Covid-19, Aggrawal added, "We have allowed the use of Hydroxychloroquine for healthcare workers dealing with Covid-19 patients or high risk contacts of the patients though there is limited evidence of its efficacy. There is not sufficient evidence to use it at community level."