Katalin Karikó is an unsung hero. For decades, she has quietly devoted her career to studying and promoting mRNA technology—technology that is now the basis of the Covid vaccines being distributed across the globe. Karikó was born in Hungary and began her scientific career there, but immigrated to Philadelphia in 1985 with her husband, daughter, and the equivalent of $1200 stuffed in her daughter's teddy bear for safe keeping. Her first ten years in the U.S. were not smooth; her idea that mRNA could be used to fight disease was, at the time, considered too radical and risky. She was demoted from her job at a Penn lab and was diagnosed with cancer shortly thereafter. But she didn't give up on her mRNA thesis; in 2006 she cofounded a firm to develop mRNA drugs, and in 2013 joined BioNTech as a senior vice president. She is also now the head of its RNA protein replacement therapies. “I never doubted it would work,” she told the Guardian shortly before the Pfizer/BioNTech vaccine got emergency use authorization from the federal government. “I always wished that I would live long enough to see something that I’ve worked on be approved.” Subscribe to FORBES: null Stay Connected Forbes newsletters: https://newsletters.editorial.forbes.com/ Forbes on Facebook: http://fb.com/forbes Forbes Video on Twitter: http://www.twitter.com/forbes Forbes Video on Instagram: http://instagram.com/forbes More From Forbes: http://forbes.com/ Forbes covers the intersection of entrepreneurship, wealth, technology, business and lifestyle with a focus on people and success.