Officials in China confirmed on Monday that humans can be infected by other humans with the new, fast-spreading virus that has triggered alarm bells across the world, including in India where officials have now begun a sweeping identification of people who are or may be flying in from any Chinese city.

According to officials in Beijing, 14 medical staff have been infected by the previously unseen coronavirus, the number of patients has more than trebled, and new infections have been reported from more Chinese cities – confirming fears that the virus is highly contagious.

In India, health ministry officials reached out to the embassy in China and to immigration officials for details of inbound travellers from the affected regions, including foreigners as well as Indian citizens.

Among them are at least 500 Indians studying in medical colleges in Wuhan, the ground zero for the outbreak.

“There are apparently close to 500 students in different medical colleges; we have asked the officials there to send us the list. Immigration has also been alerted here; anyone coming from China will be screened irrespective of the reason of travel,” said a senior health ministry official, asking not to be named.

According to the official, people arriving from China are being subjected to thermal screening at the seven international airports that have inbound connections to Chinese cities: Delhi, Mumbai, Kolkata, Chennai, Bengaluru, Hyderabad and Kochi. Screening at the first three have been on since Friday.

Till now, the thermal screening has not led to any infection being detected, the official added.

The department has also written to the ministry of external affairs (MEA) for details of all visas sought from Wuhan since December 31, 2019, the official added. “As for e-Visas, the ministry of home affairs is being approached,” this person said.

Representatives from the foreign ministry did not respond to requests for a comment.

Adding to the difficulties of containing the virus, hundreds of millions will be travelling domestically and abroad during the Lunar New Year holiday that starts this week.

This is also the time when most foreign students travel back to their countries during this time of the year.

The outbreak appeared to widen as officials in China said the virus has spread to more cities, including the capital Beijing and Shanghai, while the number of patients more than tripled and a third person died.

Zhong Nanshan, director of China’s State Key Laboratory of Respiratory Disease, said transmission between humans was behind at least one confirmed case in Wuhan – a city that was connected to at least 95% of the cases — and also infections in two families in south China’s Guangdong province.

Chinese President Xi Jinping said on Monday the country will focus on curbing the spread, state television reported.

“People’s lives and health should be given top priority and the spread of the outbreak should be resolutely curbed,” it quoted Xi as saying.

The confirmation of person-to-person transmission is worrying because it could accelerate the spread of the virus, which, until now, was believed to be purely zoonotic (spreading from animals to humans).

The virus belongs to the same family of coronaviruses as Severe Acute Respiratory Syndrome (SARS), which killed nearly 800 people globally during a 2002-03 outbreak that also started in China.

Its symptoms include fever and difficulty in breathing, which are similar to many other respiratory diseases and pose complications for screening efforts.

The WHO also said that the situation was still evolving, and preliminary investigations suggested link to a seafood market in Wuhan.

“Coronaviruses are highly infectious and very prone to mutation; it’s difficult to predict their behaviour. Since it is an acute respiratory tract infection, its spread is easy and fast. However, India doesn’t need to panic as of now,” said Dr Ekta Gupta, senior microbiologist at a Delhi government-run hospital.

With the infection spreading to other countries such as Japan and Thailand, India on Friday issued a travel advisory asking passengers to maintain personal hygiene such as hand washing, and follow respiratory etiquettes such as covering mouth when coughing or sneezing.

“…one should avoid contact with live animals and consumption of raw and undercooked meats. Also, as far as possible avoid travel to farms, live animal markets or where animals are slaughtered,” Indian authorities advised passengers travelling from the region.

According to the health ministry official quoted above, hospitals attached to the seven airports that have incoming flights from Chinese cities has been reviewed for provisions of isolation and critical care facilities.

“Immigration officers manning the counters have been sensitised at these airports,” the official said.

An official from the Indian Council of Medical Research’s National Institute of Virology in Pune confirmed there has been no sample lifted of any suspected case for testing so far.

“There is no evidence of human to human transmission as of now. It appears to be a new zoonotic Corona virus, and the current pattern suggests that the new strain isn’t as virulent as H1N1 that broke out in 2009. However, we are prepared to investigate if necessary,” said the official.