Coronavirus: A new type of vaccine using RNA could help defeat COVID-19
A century ago, on July 26, 1916, a viral disease swept through New York. Within 24 hours, new cases of polio increased by more than 68%. The outbreak killed more than 2,000 people in New York City alone. Across the United States, polio took the lives of about 6,000 people in 1916, leaving thousands more paralyzed.