Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. COVID-19 Vaccine Development Will Follow Scientific Process, US Experts Vow Katherine Gypson Development of a COVID-19 vaccine will not be compromised by outside political considerations, U.S. health experts told lawmakers Wednesday. The nation's top health officials said the six vaccine candidates currently in large-scale U.S. trials are expected to deliver a result that can be distributed to the most vulnerable populations -- including health care workers and first responders -- by the end of this year. "We need to follow the process because the process works," U.S. Surgeon General Jerome Adams told Senate lawmakers Wednesday. .