After China took the unprecedented step of locking down Wuhan on Thursday morning to attempt to curb the further spread of a new and deadly virus, a number of other cities in Hubei province have been made to follow suit.

At midnight on Friday, the city of Huanggang shut down its city buses, long-distance bus station, and railway station, according to a government notice. Located about 75 kilometers away from Wuhan, Huanggang is a city of 7.5 million people.

The nearby city of Ezhou, with a population of over a million, has also closed down its buses, trains, and ferries. Smaller cities like Chibi and Zhijiang have enacted similar restrictions as of early on Friday morning.

For its part, Shanghai has canceled all bus routes to Hubei

This all comes as a coronavirus that originated in a Wuhan wet market last month has gone on to infect at least 633 people across the city, claiming the lives of 17 so far. The virus is from the same family as SARS, which caused a large-scale panic in 2002/2003, killing more than 600 people in China.

However, not even during the SARS panic did China opt to put entire cities under lockdown, making this entirely new territory.

Though, virus expert Guan Yi, who helped to identify the source of the SARS, has questioned whether this unprecedented move will prove effective, noting that those carrying the virus have already had weeks to leave Wuhan and many have already done so, traveling to spend the Chinese New Year with their families.