“We will continue to prevent the risk of a secondary spread caused by sporadic domestic cases and imported cases, with timely detection, precise prevention and control,” Mi said.

The outbreak that began in central China in December has become a global pandemic, with more than 670,000 people infected worldwide and nearly 32,000 deaths as of Sunday. The United States now has the most confirmed cases, followed by Italy and China.

Chinese officials have taken a series of measures to prevent imported cases from starting a second wave of infections. From midnight on Friday, most foreigners were barred from entering the country, with entry visas suspended as a “temporary measure”.

The number of international flights has also been cut, reducing the daily tally of passengers entering the country from 25,000 to 5,000, according to the Civil Aviation Administration of China.

Passengers arriving in a number of cities from abroad are being tested for the virus and quarantined.

Local governments have also introduced measures to contain further outbreaks.

In Beijing, international flights are being redirected to 12 airports in surrounding cities – including Tianjin, Hohhot in Inner Mongolia and Shanghai – to lessen the disease control burden in the capital.

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The southern city of Shenzhen, which borders Hong Kong, announced this week that anyone entering the city through Shenzhen Bay must be tested for the virus and fill out a health declaration.

In Shanghai, anyone arriving from abroad will go into quarantine for 14 days at a designated facility.

“It’s a relief to know that we’re unlikely to see another explosion of domestic cases,” Yang said.

“I don’t think [we’ll see this] but imported cases still pose a high risk, so I support the temporary travel restrictions.”