Covid-19 vaccine sales which are on track to provide a "durable" revenue stream in the wake of the pandemic.The drugmaker reported a jump in first-quarter profits based on surging revenues, with nearly one-fourth of sales coming from Covid-19 vaccines.With German partner BioNTech, the pharma giant is ramping up vaccine production and now estimates 2021 revenues of $26 billion from the vaccine, up from the $15 billion projected in February.But the surging profits have drawn criticism as governments face pressure to step in to ensure vaccines are provided to underserved countries.Pfizer, which says it is on the cusp of winning US approval for individuals 12 to 15 years old to receive its vaccine, is holding talks with "basically all.