Covid-19 downturn, and nations should remove trade barriers on medical technologies to aid the recovery, the IMF chief said on Thursday.The call from Managing Director Kristalina Georgieva ahead of this week's G20 leaders summit comes as countries grapple with the fallout from a pandemic that has killed hundreds of thousands and caused a sharp contraction in growth."While a medical solution to the crisis is now in sight, the economic path ahead remains difficult and prone to setbacks," Georgieva said in a blog post.Major pharmaceutical companies are now closing in on vaccines against the virus, amid a global spike in cases that has caused some countries to reimpose restrictions to curb transmission."The resurgence in infections is a.