The United States will know by the end of the year or the beginning of 2021 whether a coronavirus vaccine is safe and effective, Dr. Anthony Fauci, the nation’s leading infectious diseases doctor, said during a Facebook Live event with…

As the coronavirus continues to spread, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, explains how the virus transmits from person to person and why it is more serious than the common cold or seasonal…