The announcement came as the Washington, DC health services identified a total of ten cases of novel coronavirus infections.
"Today, I want to announce that I'm declaring both a state of emergency and a public health emergency in Washington, DC," Bowser said at a briefing on Wednesday. "This is an administrative action largely. It will give me more authority to implement and fund the measures that we need to monitor a response to COVID-19 in our community."
Bowser explained that the declaration gave her abilities to request US federal disaster assistance, mandate medical quarantines and outlaw price gouging.
City authorities recommend that non-essential gatherings of 1,000 or more people, including conferences and conventions, be postponed or canceled through 31 March.
Bowser added, "We also recommend that any social, cultural, entertainment events where large crowds are gathered also be reconsidered by their organizers. This is in effect through March 31."
City authorities have set up an emergency operation center and are preparing for potential suspension of schooling.
On Wednesday, six additional novel coronavirus infections had been identified bringing the total of presumptive cases in Washington, DC to ten.
According to the latest data collected by Johns Hopkins University, more than 1,100 cases of novel coronavirus infections have been confirmed in the United States and 32 people have died from the disease.