Read MoreRussian President Vladimir Putin claims his country is now using the world’s first COVID-19 vaccine and one of his daughters has already been inoculated. Russian authorities say medical workers, teachers and others in high-risk groups will get the vaccine first. Dr. David Agus joins “CBS This Morning” to explain what we know about the vaccine and whether it changes how the U.S. and other countries approach vaccine development.Russian President Vladimir Putin claims his country is now using the world’s first COVID-19 vaccine and one of his daughters has already been inoculated. Russian authorities say medical workers, teachers and others in high-risk groups will get the vaccine first. Dr. David Agus joins “CBS This Morning” to explain what we know about the vaccine and whether it changes how the U.S. and other countries approach vaccine development.