FALLS CHURCH, Va. (AP) — Virginia now has 30 people who have tested positive for the coronavirus, up from 17 a day ago, Gov. Ralph Northam said Friday.

Northam made the announcement Friday at a visit to a Richmond hospital. The state Department of health did not yet release any details on where the 12 new cases are located.

Northam declared a state of emergency Thursday and said he was canceling all state conferences and large events for the next 30 days. He urged local governments and private organizers to follow suit. He also announced new restrictions on travel for state workers.

Dr. Lilian Peake, the state epidemiologist, said there is so far no sign of “community spread” of the virus in Virginia.

The coronavirus has infected around 136,000 people worldwide and killed more than 5,000. For most people, the virus causes only mild or moderate symptoms, such as fever and cough. But for some, it can cause more severe illness, including pneumonia. The vast majority of people who contract it recover within weeks.

Meanwhile, schools systems in the state struggled with the decision whether to remain open. Virginia’s largest school system defended its decision to stay open during the coronavirus pandemic only to capitulate hours later in the face of angry parents, exemplifying the difficult decision schools faced throughout the state.

Fairfax County Public Schools Superintendent Scott Brabrand appeared at a news conference Thursday afternoon and defended the decision to stay open, even though neighboring Loudoun County and the entire state of Maryland, just across the Potomac River, announced plans for an extended closure.

By 8 p.m. Thursday, the superintendent emailed a note to all parents with a quote from the county’s health director supporting his decision to stay open. She noted that all of the cases in Virginia, so far, could be traced to international travel or direct exposure to someone with the virus. Maryland, on the other hand, had seen its first case of “community spread” in which a person had contracted the illness without such a direct connection.

“Schools serve an important and vital function in our community. Keeping schools open, whenever possible, is critical at this time,” said Dr. Gloria Addo-Ayensu. “If, and when, it is determined that our contact investigations show any connection to the school system, we would provide closure guidance and recommendations.

Brabrand did, though, announce cessation of all after-school activities, sports, and community use of the schools through April 12.