How mistakes redefined the vaccine process | CNBC Explains

The last time the U.S. government tried to create a vaccine at “warp speed” in 1976 ended in a fiasco. As governments and organizations race to develop a new vaccine in record time, CNBC’s Timothyna Duncan explores the challenges in vaccinating more than 7 billion people worldwide. ----- Subscribe to us on YouTube: http://cnb.cx/2wuoARM Subscribe to CNBC International TV on YouTube: https://cnb.cx/2NGytpz Like our Facebook page:   / cnbcinternational   Follow us on Instagram:   / cnbcinternational   Follow us on Twitter:   / cnbci