Dr. Sanjay Gupta takes an in-depth look at the proven science of vaccines and the backlash against them amidst the backdrop of COVID-19 with increasing numbers of parents choosing not to vaccinate their children pre-COVID. More than a year into the COVID-19 pandemic and after over half a million American lives lost, there is now finally hope.  Currently, there are three vaccines available in the United States, and scientists say if enough people get vaccinated, this pandemic will come to an end, and life can return to normal. Yet polls show that one-third of Americans are still hesitant or downright unwilling to get a COVID-19 vaccine. Anti-vaccine sentiment is not new — the movement has a long history. A history that Dr. Sanjay Gupta was investigating and filming before the COVID-19 pandemic began.