In late 2019, the emergence of the SARS-CoV-2 virus, which causes COVID-19, was initially not considered a significant threat by much of the world. However, by March 2020, it became apparent that drastic action was needed as the virus spread rapidly, leading to its declaration as a pandemic by the World Health Organization. While the United States is now in a better position, with widely available vaccines and less deadly variants, the lessons learned and toll taken by the more than 1 million Americans who lost their lives will continue to reverberate. COVID-19 proved to be a different kind of virus, with widespread asymptomatic or mildly symptomatic transmission, making it difficult to contain. Furthermore, as a new virus, there was limited data available to scientists on its operation and transmission. By March 2020, the United States had reported over 100,000 cases and a death toll exceeding 1,500.