Two Sydney high schools closed on Monday after three students tested positive for COVID-19 as health authorities ramped up preparations for a larger outbreak with the number of infections in Australia exceeding 80.

St Patrick’s Marist College Dundas in the city’s northwest will remain shut on Tuesday after two year-10 students were diagnosed with coronavirus. Willoughby Girls High School in north Sydney also closed from Monday after a year-7 pupil tested positive.

“Obviously, when you have new cases at a school, it’s cause for concern, because we want to make sure that we move as quickly as possible to require isolation of others who might have had contact with the confirmed cases,” New South Wales minister for health Brad Hazzard told media on Monday.

The announcements come only days after another high school in Sydney shut down when a 16-year-old student tested positive.

Epping Boys High School reopened on Monday though nearly 70 students and staff who had close contact with the infected student remained in self isolation.

Globally, the coronavirus has killed about 3,600 and infected 107,000 as the outbreak reached more countries and caused hefty economic carnage and stock market losses, prompting central banks to ease monetary policies. Three people have died in Australia.

The state of Victoria also recorded a jump in the number of cases after two people who recently traveled to the United States and one who returned from Iran were diagnosed with COVID-19.

“This is a public health emergency of an unprecedented nature that our nation and that the entire global community is facing,” Victorian Health Minister Jenny Mikakos told a televised briefing.

“We do anticipate that this likely pandemic will have significant impacts on our health system. This has been my absolute focus, making sure that our system is prepared to respond.”

Chief Medical Officer Brendan Murphy told reporters in Melbourne the vast majority of cases in Australia were return travelers, with only one instance of community transmission.

“At the moment, we’re focusing very aggressively on tracing and isolating contacts, because all of the evidence suggests that the best way to temper, delay and reduce the size of any outbreak in Australia is to contain it,” he said.

Murphy said health authorities have been contacting general practitioners, sourcing more masks and setting up special clinics in preparation for a possible pandemic.

“Australia remains extremely well prepared for further growth in this virus,” he added.

Reuters