The first testing in humans of an experimental vaccine for the new coronavirus began on Monday, the National Institute of Allergy and Infectious Diseases announced.

The main goal of this first set of tests is to find out if the vaccine is safe. If it is, later studies will determine how well it works.

The trial was “launched in record speed,” Dr. Anthony Fauci, the institute’s director, said in a statement.

Such rapid development of a potential vaccine is unprecedented, and it was possible because researchers were able to use what they already knew about related coronaviruses that had caused other diseases outbreaks, SARS and MERS.